atw 2019-02

inforum

nucmag.com

2019

2

71

Contribution of NPPs

to the Energy Transition

79 ı Serial | Major Trends in Energy Policy and Nuclear Power

Wind Energy in Germany and Europe

90 ı Spotlight on Nuclear Law

The New Radiation Protection Law (I): Official Approvals

91 ı Environment and Safety

Piping Stress Analysis of Safety Injection System

of Typical PWR Power Reactor

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106 ı Special Topic | A Journey Through 50 Years AMNT

1971 DAtF-KTG-Meeting on Reactors in Bonn

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Technolution – The Co-Evolution

Between Techology and Humankind

› Matthias Horx ‹

Trend Researcher and Futurologist,

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Tuesday, 7 th Mai 2019, 6:30 pm

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Celebrate with us our 50 th anniversary


atw Vol. 64 (2019) | Issue 2 ı February

The Same Procedure

63

Anyone who is enthusiastic about the construction of a nuclear power plant today must consider the fact that this

plant will technically still run in 80 or even 100 years under politically reliable framework conditions. For nuclear power

plants that are in operation today, even for 30 to 40 years, technical operating lives of 60 years are a matter of course,

and in the USA, for example, 80 years are undergoing technical and regulatory evaluation. As far as the guarantee of

continued highest safety levels is concerned, statements are very clear: A “retirement loan” is not granted, nor does it

have to, since highest safety is also guaranteed for running plants by ongoing quality management and for new technical

findings by retrofitting.

Such long-term prospects also raise the question of

whether sufficient nuclear fuel is available worldwide as a

raw material at all. The answer is given periodically, every

two years, with the comprehensive report “Uranium:

Resources, Production and Demand” by the Nuclear

Energy Agency (NEA) of the Organisation for Economic

Development (OECD) and the International Atomic

Energy Agency (IAEA). Since the mid-1960s, the two

organizations have been publishing this analysis of the

global nuclear fuel market, reserves and resources. The

Red Book offers a detailed and reliable insight into the

current situation of the entire uranium and nuclear fuel

supply. The Red Book also provides an outlook on demand

and supply forecasts for the coming decades. The data in

the 27 th edition, which has now been published, have been

compiled with the support of 41 member states of both

organisations and analyses by NEA and IAEA experts. They

reflect the state of knowledge on 45 countries with nuclear

fuel resources and/or requirements as of 1 January 2017.

In addition, other aspects of nuclear fuel supply are

outlined, such as environmental protection and price

development.

The opening statement is unequivocal: With the

demand level of 2016, sufficient uranium is known

worldwide to supply for 130 years. Further nuclear fuel

resources have been identified, but are not yet taken into

account because they are not strategically necessary!

On the uranium supply side, the Red Book again

identifies an increase in resources compared to 2015:

According to the list classified by costs step by step, a total

of 7.989 million tonnes of uranium at production costs


atw Vol. 64 (2019) | Issue 2 ı February

EDITORIAL 64

Es bleibt dabei

Liebe Leserin, lieber Leser, wer sich heute für den Bau eines Kernkraftwerks begeistert, muss damit rechnen,

dass diese Anlage unter politisch verlässlichen Rahmenbedingungen technisch gesehen noch in 80 oder gar 100 Jahren

laufen wird. Für Kernkraftwerke, die heute in Betrieb sind, auch schon seit 30 bis 40 Jahren, sind technische Laufzeiten

von 60 Jahren eine Selbstverständlichkeit und zum Beispiel in den USA sind 80 Jahre in der technischen und

regulatorischen Prüfung. Was die Gewährleistung von weiterhin höchsten Sicherheitsniveaus betrifft, so sind Aussagen

sehr eindeutig: Ein „Alterskredit“ wird nicht gewährt, muss er auch nicht, da höchste Sicherheit auch bei laufenden

Anlagen durch das laufende Qualitätsmanagement und bei neuen technischen Erkenntnissen durch Nachrüstungen

gewährleistet wird.

1) Uranium 2018:

Resources, Production

and Demand,

A Joint Report by

the OECD Nuclear

Energy Agency and

the International

Atomic Energy

Agency, NEA No.

7413, Paris, 2018

Mit solchen Langfristperspektiven stellt sich auch die

Frage, ob überhaupt ausreichend Kernbrennstoff weltweit

als Rohstoff zur Verfügung steht. Die Antwort darauf gibt

es periodisch, alle zwei Jahre, mit dem umfassenden

Bericht „Uranium: Resources, Production and Demand“

von Nuclear Energy Agency (NEA) der Organisation for

Economic Development (OECD) und Internationaler

Atom energie-Organisation (IAEO). Seit Mitte der 1960er-

Jahre veröffentlichen die beiden Organisationen diese

Analyse zum weltweiten Kernbrennstoffmarkt, den

Reserven und Ressourcen. Das Red Book bietet einen

detaillierten und verlässlichen Einblick in die aktuelle

Situation der gesamten Uran- und Kernbrennstoff versorgung.

Zudem liefert das Red Book einen Ausblick auf

die Bedarfs- und Versorgungsprognose der kommenden

Jahrzehnte. Die Daten der jetzt veröffentlichten 27. Ausgabe

sind mit Unterstützung von inzwischen 41

Mitgliedsstaaten beider Organisationen sowie Analysen

der Experten von NEA und IAEO ermittelt worden. Sie

spiegeln den Wissensstand zu 45 Staaten mit Kernbrennstoffressourcen

und/oder -bedarf zum Stichtag 1. Januar

2017 wider. Darüber hinaus werden weitere Aspekte der

Kernbrennstoffversorgung umrissen, wie z.B. Umweltschutz

und Preisentwicklung.

Eindeutig ist das Eingangsstatement: Mit dem Bedarfsniveau

des Jahres 2016 ist weltweit ausreichend Uran

zur Versorgung für 130 Jahre bekannt. Weitere Kernbrennstoffressourcen

sind identifiziert, werden aber, da

strategisch nicht erforderlich, noch nicht berücksichtigt!

Aufseiten der Uranversorgung identifiziert das Red

Book wiederum einen Ressourcenzuwachs im Vergleich

zum Jahr 2015: Entsprechend der stufenweise nach Kosten

klassifizierten Aufstellung werden am Stichtag 1. Januar

2017 insgesamt 7,989 Mio. t Uran zu Gewinnungskosten


Kommunikation und

Training für Kerntechnik

Suchen Sie die passende Weiter bildungs maßnahme im Bereich Kerntechnik?

Wählen Sie aus folgenden Themen: Dozent/in Termin/e Ort

3 Atom-, Vertrags- und Exportrecht

Das Recht der radioaktiven Abfälle RA Dr. Christian Raetzke 05.03.2019

17.09.2019

Ihr Weg durch Genehmigungs- und Aufsichtsverfahren RA Dr. Christian Raetzke 02.04.2019

22.10.2019

Atomrecht – Navigation im internationalen nuklearen Vertragsrecht Akos Frank LL. M. 03.04.2019 Berlin

Atomrecht – Was Sie wissen müssen

Export kerntechnischer Produkte und Dienstleistungen –

Chancen und Regularien

3 Kommunikation und Politik

RA Dr. Christian Raetzke

Akos Frank LL. M.

RA Kay Höft M. A.

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Dr.-Ing. Wolfgang Steinwarz

Berlin

Berlin

04.06.2019 Berlin

12.06. - 13.06.2019 Berlin

Schlüsselfaktor Interkulturelle Kompetenz –

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Public Hearing Workshop –

Öffentliche Anhörungen erfolgreich meistern

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Dr. Nikolai A. Behr 05.11. - 06.11.2019 Berlin

3 Rückbau und Strahlenschutz

In Kooperation mit dem TÜV SÜD Energietechnik GmbH Baden-Württemberg:

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RA Dr. Christian Raetzke

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18.03. - 19.03.2019

04.04. - 05.04.2019

25.06. - 26.06.2019

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24.09. - 25.09.2019 Berlin

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Advancing Your Nuclear English (Aufbaukurs) Devika Kataja 10.04. - 11.04.2019

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Enhancing Your Nuclear English Devika Kataja 22.05. - 23.05.2019 Berlin

3 Wissenstransfer und Veränderungsmanagement

Berlin

Erfolgreicher Wissenstransfer in der Kern technik –

Methoden und praktische Anwendung

Veränderungsprozesse gestalten – Heraus forderungen

meistern, Beteiligte gewinnen

Dr. Tanja-Vera Herking

Dr. Christien Zedler

Dr. Tanja-Vera Herking

Dr. Christien Zedler

26.03. - 27.03.2019 Berlin

26.11. - 27.11.2019 Berlin

Haben wir Ihr Interesse geweckt? 3 Rufen Sie uns an: +49 30 498555-30

Kontakt

INFORUM Verlags- und Verwaltungs gesellschaft mbH ı Robert-Koch-Platz 4 ı 10115 Berlin

Petra Dinter-Tumtzak ı Fon +49 30 498555-30 ı Fax +49 30 498555-18 ı seminare@kernenergie.de

Die INFORUM-Seminare können je nach

Inhalt ggf. als Beitrag zur Aktualisierung

der Fachkunde geeignet sein.


atw Vol. 64 (2019) | Issue 2 ı February

66

Issue 2 | 2019

February

CONTENTS

Contents

Editorial

The Same Procedure E/G 63

Inside Nuclear with NucNet

Financing New Nuclear: Is RAB Model the Right Way Forward? 68

DAtF Notes 69

Calendar 70

Feature | Major Trends in Energy Policy and Nuclear Power

Contribution of Nuclear Power Plants

to the Energy Transition in Germany 71

Serial | Major Trends in Energy Policy and Nuclear Power

Wind Energy in Germany and Europe 79

Spotlight on Nuclear Law

The New Radiation Protection Law (I): Official Approvals G 90

Environment and Safety

Piping Stress Analysis of Safety Injection System

of Typical PWR Power Reactor 91

Environment and Safety

Research for the Adequacy Analysis of Plant System Behaviors

During Abnormal Conditions 95

Operation and New Build

Design of Control System for On-line Ultrasonic Testing Device

of Nuclear Power Hollow Flange Bolt Based on LabVIEW 98

Research and Innovation

Simulation of KSMR Core Zero Power Conditions

Using the Monte Carlo Code Serpent 103

Special Topic | A Journey Through 50 Years AMNT

1971 DAtF-KTG-Meeting on Reactors in Bonn G 106

Cover:

Isar NPP in Germany. Isar 2 (left) was the

third NPP worldwide that produced more

than 350 billion kWh of electricity.

Copyright: PreussenElektra GmbH

KTG Inside 112

News 113

Nuclear Today

Nuclear Has Every Reason to Plan for a New Energy Horizon 118

G

E/G

= German

= English/German

Imprint 102

Contents


atw Vol. 64 (2019) | Issue 2 ı February

Feature

Major Trends in Energy Policy

and Nuclear Power

71 Contribution of Nuclear Power Plants

to the Energy Transition in Germany

67

CONTENTS

Denis Janin, Eckart Lindwedel,

Volker Raffel, Graham Weale, James Cox and Geir Bronmo

Serial | Major Trends in Energy Policy and Nuclear Power

79 Wind Energy in Germany

and Europe

Thomas Linnemann and Guido S. Vallana

Spotlight on Nuclear Law

90 The New Radiation Protection Law (I): Official Approvals

Das neue Strahlenschutzrecht (I): Genehmigungen

Christian Raetzke

Environment and Safety

91 Piping Stress Analysis of Safety Injection System

of Typical PWR Power Reactor

Mazhar Iqbal, Agha Nadeem, Tariq Najam,

Kamran Rasheed Qureshi, Waseem Siddique and Rustam Khan

Special Topic | A Journey Through 50 Years AMNT

106 1971 DAtF-KTG-Meeting on Reactors in Bonn

DAtF-KTG-Reaktortagung 1971 in Bonn

Nuclear Today

118 Nuclear Has Every Reason to Plan for a New Energy Horizon

John Shepherd

Contents


atw Vol. 64 (2019) | Issue 2 ı February

68

INSIDE NUCLEAR WITH NUCNET

Financing New Nuclear:

Is RAB Model the Right Way Forward?

David Dalton, NucNet

The United Kingdom (UK) is considering a new method of funding to make sure new plants can get built.

The UK government has confirmed it is exploring

the “right ways” to finance new nuclear,

including through potential government investment

in the Wylfa Newydd nuclear power station on the

isle of Anglesey in North Wales and a regulated asset base,

or RAB, model for future projects.

Business secretary Greg Clark said in a speech on the

future of the energy market that “if nuclear is sufficiently

competitive, then it is worth, in my view, turning that

option into a commitment.”

He said there has been “some criticism” of the

prospective cost of the Hinkley Point C nuclear station

project, but in its efforts to bring down costs the government

is looking into financing options for new-build.

“It is also why we recently announced a nuclear industry

deal with its emphasis on the need to reduce the costs [of

new nuclear] by 30 % through increasing modularisation

and advanced manufacturing,” Mr Clark said.

France’s state-controlled EDF, through its UK division

EDF Energy, is building two EPR units at Hinkley Point C

with the financial participation of China’s General Nuclear

Power Corporation (CGN). The cost of the project is

estimated at almost £ 20 bn.

The financing for the project proved controversial.

The deal struck with EDF Energy to build what is Britain’s

first new nuclear power project in a generation has been

criticised by the National Audit Office (NAO) because it

guarantees the company a strike price of £ 92.50 per

megawatt- hour of electricity, well above current market

prices.

The agreement means EDF will receive £ 92.50 for each

MWh of electricity from the station that it sells into the

market for 35 years. EDF will receive top-up payments –

ultimately paid for by electricity bill-payers – if the market

price is lower. Conversely, payments will flow in the

opposite direction if wholesale prices rise above the strike

price.

The core of the issue is the upfront cost of financing major

infrastructure projects like nuclear plants. According to

the NAO it has not been commercially viable for private

developers to build new generating capacity without

government support. “The forecast revenues available in

the wholesale electricity market do not cover the high

upfront costs and other risks of building, operating and

decommissioning low-carbon power plants,” the NAO said.

Mr Clark’s speech is the clearest indication yet that the

government is open to RAB, essentially a type of contract

drawn up with the backing of government which calculates

the costs and profits of a project before it is started, and

allocates an investor’s profits from day one.

A government regulator sets a fixed number, the RAB,

which attempts to account for all the future costs involved

in the completion of a project. The regulator then also sets

a fixed rate of return for the investors based on those costs.

Dieter Helm, the British economist and academic, says

RAB would solve the problem for nuclear developers of

“time inconsistency and the operating contract” – the risks

to the developer that the government will renege on its

part of the deal and that the plant will be forced off the

system by the investment decisions of others, in particular

where low-carbon investment is decided by and subsidised

by government.

“The RAB mechanism is honoured by the regulator and

the regulator is itself backed by statute, so ultimately this

duty is backed by the government,” Mr Helm wrote in a

recent paper.

“Because there is regulatory protection against time

inconsistency and because ultimately the government

stands behind the regulator and the duty to finance

functions, investors treat the RAB as a very solid

securitisable asset.”

Nuclear power is “always and everywhere political”

because it involves capital intensive and long-lived assets,

and because it comes with environmental, military and

technology specific risks on a scale which no private

market can handle on its own, Mr Helm said.

Nuclear waste lasts for many generations and plans

for the storage of that waste remain a work-in-progress.

Decommissioning is far into the future and cannot be left

to limited liability private companies.

Nuclear has important military dimensions and

terrorist- related risks. Accidents, however unlikely, may

create large-scale consequences, which private limited

liabilities companies cannot fully provide for.

According to Mr Helm, these characteristics that

nuclear is a societal and political matter, over many

generations. Nuclear safety regulation, nuclear funds for

decommissioning, nuclear waste storage and nuclear

security and secrecy remain for the state, and cannot be

contracted out to private project developers.

What can be contracted out to private companies is

the construction and operation of nuclear power stations

– in principle. In practice, most nuclear developers are

state-owned, in whole or in part, and all have close links to

government.

“This is because of the technology and also the specific

endemic challenges of project developments,” Mr Helm

said. “There are unsurprisingly no purely private sector

nuclear projects anywhere in the world.”

Apart from Hinkley Point C, which is in the early stages

of construction, there are three other new nuclear projects

on the drawing board in the UK.

Horizon Nuclear Power is planning to build two UK

Advanced Boiling Water Reactors at Wylfa Newydd. CGN

and EDF Energy have formed a joint venture with plans to

build a single China-designed HPR1000 plant at Bradwell

B in Essex, southeast England, a project CGN has said

could use the RAB model. EDF wants to begin construction

of two EPR units at the Sizewell C nuclear power station on

the east coast of England by the end of 2021.

However, Toshiba announced earlier this month it had

decided to wind up NuGen, the company overseeing plans

Inside Nuclear with NucNet

Financing New Nuclear: Is RAB Model the Right Way Forward?


atw Vol. 64 (2019) | Issue 2 ı February

Notes

Return of Waste

from Nuclear Fuel Reprocessing

Until 2005, the reprocessing of spent nuclear fuel was the planned

way. By the year 1994, it was even the legal requirement. Therefore

the spent fuel elements were transported to France and Great

Britain for reprocessing. For this purpose, the operators of the

German nuclear power plants have signed contracts with the

operators of the reprocessing facilities in La Hague and Sellafield.

The radioactive waste caused by the reprocessing will be returned

to Germany. To reflect this DAtF has published a new edition of the

brochure on the management of the return of waste from nuclear

fuel reprocessing.

LA HAGUE

SELLAFIELD

DATF EDITORIAL NOTES

69

pp

How does the conditioning of the radioactive waste work?

pp

How is this waste stored temporarily?

pp

Which organizations are responsible for authorization?

Answers to these questions and more information can be found in

the new edition of:

Return of Waste

from Nuclear Fuel Reprocessing

33

Now available for download at www.kernenergie.de

(German)

Rücknahme von Abfällen

aus der Wiederaufarbeitung

For further details please contact:

Nicolas Wendler

DAtF

Robert-Koch-Platz 4, 10115 Berlin, Germany

E-mail: presse@kernenergie.de

www.kernenergie.de

to build three Westinghouse Generation III+ AP1000 units

at the Moorside site in northwest England.

Toshiba said it was winding up NuGen because of its

inability to find a buyer and the ongoing costs it was

incurring. The company said finding the right financing

model was an issue. Before the wind-up was confirmed,

NuGen chief executive Tom Samson said the RAB model

should be considered, although it was not clear if this was

ever the case.

Author

NucNet

The Independent Global Nuclear News Agency

Editor responsible for this story: David Dalton

Editor in Chief, NucNet

Avenue des Arts 56

1000 Brussels, Belgium

www.nucnet.org

DAtF Notes


atw Vol. 64 (2019) | Issue 2 ı February

Calendar

70

2019

CALENDAR

05.02.-07.02.2019

Nordic Nuclear Forum. Helsinki, Finland, FinNuclear,

www.nordicnuclearforum.fi/conference

25.02.-26.02.2019

Symposium Anlagensicherung. Hamburg,

Germany, TÜV NORD Akademie, www.tuev-nord.de

03.03.-07.03.2019

WM Symposia – WM2019. Phoenix, AZ, USA,

www.wmsym.org

05.03.-06.03.2019

VI. International Power Plants Summit.

Istanbul, Turkey, INPPS Fair,

www.nuclearpowerplantssummit.com

10.03.-15.03.2019

83. Annual Meeting of DPG and DPG Spring

Meeting of the Atomic, Molecular, Plasma Physics

and Quantum Optics Section (SAMOP),

incl. Working Group on Energy. Rostock, Germany,

Deutsche Physikalische Gesellschaft e.V.,

www.dpg-physik.de

10.03.-14.03.2019

The 9 th International Symposium On

Supercritical- Water-Cooled Reactors (ISSCWR-9).

Vancouver, British Columbia, Canada, Canadian

Nuclear Society (CNS), www.cns-snc.ca

11.03.-13.03.2019

18 th Workshop of the European ALARA Network:

ALARA in Decommissioning and Site Remediation.

Marcoule, France, European ALARA Network

www.eu-alara.net

11.03.-12.03.2019

Carnegie International Nuclear Policy Conference.

Washington D.C., U.S.A., Carnegie Endownment for

International Peace, carnegieendowment.org


24.03.-28.03.2019

RRFM 20192019 the European Research

Reactor Conference. Jordan, IGORR, the International

Group Operating Research Reactors and European

Nuclear Society (ENS), www.euronuclear.org

25.03.-27.03.2019

Cyber Security Implementation Workshop.

Boston MA, USA, Nuclear Energy Institute (NEI),

www.nei.org

01.04.-03.04.2019

CIENPI – 13 th China International Exhibition on

Nuclear Power Industry. Beijing, China,

Coastal International, www.coastal.com.hk

09.04.-11.04.2019

World Nuclear Fuel Cycle 2019. Shanghai, China,

World Nuclear Association (WNA), Miami, Florida,

USA, www.wnfc.info

ATOMEXPO 2019. Sochi, Russia,

2019.atomexpo.ru/en/

15.04.-16.04.2019

07.05.-08.05.2019

50 th Annual Meeting on Nuclear Technology

AMNT 2019 | 50. Jahrestagung Kerntechnik.

Berlin, Germany, DAtF and KTG,

www.amnt2019.com – Register Now!

15.05.-17.05.2019

1 st International Conference of Materials,

Chemistry and Fitness-For-Service Solutions

for Nuclear Systems. Toronto, Canada, Canadian

Nuclear Society (CNS), www.cns-snc.ca

16.05.-17.05.2019

Emergency Power Systems at Nuclear Power

Plants. Munich, Germany, TÜV SÜD,

www.tuev-sued.de/eps-symposium

24.05.-26.05.2019

International Topical Workshop on Fukushima

Decommissioning Research – FDR2019.

Fukushima, Japan, The University of Tokyo,

fdr2019.org

29.05.-31.05.2019

Global Nuclear Power Tech. Seoul, South Korea,

Korea Electric Engineers Association,

electrickorea.org/eng

03.06.-05.06.2019

Nuclear Energy Assembly. Washington DC, USA,

Nuclear Energy Institute (NEI), www.nei.org

03.06.-07.06.2019

World Nuclear University Short Course:

The World Nuclear Industry Today.

Rio de Janeiro, Brazil, World Nuclear University,

www.world-nuclear-university.org

04.06.-07.06.2019

FISA 2019 and EURADWASTE ‘19. 9 th European

Commission Conferences on Euratom Research

and Training in Safety of Reactor Systems and

Radioactive Waste Management. Pitesti, Romania,

www.nucleu2020.eu

24.06.-28.06.2019

2019 International Conference on the Management

of Spent Fuel from Nuclear Power Reactors.

Vienna, Austria, International Atomic Energy Agency

(IAEA), www.iaea.org

23.06.-27.06.2019

World Nuclear University Summer Institute.

Romania and Switzerland, World Nuclear University,

www.world-nuclear-university.org

21.07.-24.07.2019

14 th International Conference on CANDU Fuel.

Mississauga, Ontario, Canada, Canadian Nuclear

Society (CNS), www.cns-snc.ca

28.07.-01.08.2019

Radiation Protection Forum. Memphis TN, USA,

Nuclear Energy Institute (NEI), www.nei.org

29.07.-02.08.2019

27 th International Nuclear Physics Conference

(INPC). Glasgow, Scotland, inpc2019.iopconfs.org

04.08.-09.08.2019

PATRAM 2019 – Packaging and Transportation

of Radioactive Materials Symposium.

New Orleans, LA, USA. www.patram.org

21.08.-30.08.2019

Frédéric Joliot/Otto Hahn (FJOH) Summer School

FJOH-2019 – Innovative Reactors: Matching the

Design to Future Deployment and Energy Needs.

Karlsruhe, Germany, Nuclear Energy Division

of Commissariat à l’énergie atomique et aux

énergies alternatives (CEA) and Karlsruher Institut

für Technologie (KIT), www.fjohss.eu

04.09.-06.09.2019

World Nuclear Association Symposium 2019.

London, UK, World Nuclear Association (WNA),

www.wna-symposium.org

04.09.-05.09.2019

VGB Congress 2019 – Innovation in Power

Generation. Salzburg, Austria, VGB PowerTech e.V.,

www.vgb.org

08.09.-11.09.2019

4 th Nuclear Waste Management,

Decommissioning and Environmental Restoration

(NWMDER). Ottawa, Canada, Canadian Nuclear

Society (CNS), www.cns-snc.ca

09.09.-12.09.2019

24 th World Energy Congress. Abu Dhabi, UAE,

www.wec24.org

09.09.-12.09.2019

Jahrestagung 2019 – Fachverband für

Strahlenschutz | Strahlenschutz und Medizin.

Würzburg, Germany,

www.fs-ev.org/jahrestagung-2019

16.09.-20.09.2019

63 rd Annual Conference of the IAEA. Vienna,

Austria, International Atomic Energy Agency (IAEA),

www.iaea.org/about/governance/

general-conference

22.10.-25.10.2019

SWINTH-2019 Specialists Workshop on Advanced

Instrumentation and Measurement Techniques

for Experiments Related to Nuclear Reactor

Thermal Hydraulics and Severe Accidents.

Livorno, Italy, www.nineeng.org/swinth2019/

23.10.- 24.10.2019

Chemistry in Power Plants. Würzburg, Germany,

VGB PowerTech e.V., www.vgb.org/en/

chemie_im_kraftwerk_2019.html

27.10.-30.10.2019

FSEP CNS International Meeting on Fire Safety

and Emergency Preparedness for the Nuclear

Industry. Ottawa, Canada, Canadian Nuclear Society

(CNS), www.cns-snc.ca

12.11.-14.11.2019

International Conference on Nuclear

Decommissioning – ICOND 2019. Eurogress

Aachen, Aachen Institute for Nuclear Training GmbH,

www.icond.de

25.11.-29-11.2019

International Conference on Research Reactors:

Addressing Challenges and Opportunities to

Ensure Effectiveness and Sustainability.

Buenos Aires, Argentina, International Atomic

Energy Agency (IAEA), www.iaea.org/events/

conference-on-research-reactors-2019

This is not a full list and may be subject to change.

Calendar


atw Vol. 64 (2019) | Issue 2 ı February

Feature | Major Trends in Energy Policy and Nuclear Power

Contribution of Nuclear Power Plants to

the Energy Transition in Germany

Denis Janin, Eckart Lindwedel, Volker Raffel, Graham Weale, James Cox and Geir Bronmo

This study investigates the contribution of nuclear power plants (NPPs) to the German Energy Transition by analysing

the effects of an early closure of NPPs early 2020. According to the German law, the seven NPPs remaining today in

operation will be shut-down successively by 2022 at the latest. Until then NPPs generate competitive, CO 2 -free and

dispatchable power supporting the German power system and the other energy transition objectives. This work

quantifies the impact of an early phase-out of NPPs in Germany and at the European level. A coupled market and grid

system analysis is performed. The Pöyry’s in-house market model BID3 and the grid analysis software tool PSS/E,

simulating the electrical behaviour of the power grid using the transmission system planning, are applied. This approach

enables a consideration of power grid actual flows, model power redispatch measures and an evaluation of the

associated costs. In a nutshell a premature shut down of German NPPs already by the end of 2019 would cost over

5 billion EUR to the German social welfare, increase CO 2 emissions by up to 90 million tons and raise wholesale power

prices between 4 to 7 EUR/MWh. As for grid stability aspects, without NPPs on the grid from January 2020 onwards,

the capacity margins would be reduced by 1.5 GW, the redispatch costs of thermal power plants would increase while

the measures associated with renewables energies curtailment would decrease. This research was performed by the

independent analysis of Pöyry Management Consulting at the request of PreussenElektra in 2018.

1 Introduction

According to the German law, the seven nuclear power

plants (NPPs) remaining today in operation will be shut

down successively by 31st December 2022 at the latest, as

shown in Figure 1 [1]. Until then, NPPs generate competitive,

dispatchable and CO 2 -free power [2] supporting

the German energy transition (Energiewende) objectives.

This work quantifies the contribution of NPPs to the

German energy transition during the period 01.01.2020

until 31.12.2022. The study investigates the scenario of

an early closure of all NPPs early 2020 and focuses on

energy economics and power grid consequences. A

coupled market and grid system analysis is performed

using the market model BID3 [4] and the PSS/E tool [5]

simulating the electrical behaviour of the power grid using

the transmission system planning. This work was performed

by the independent analysis of Pöyry Management

Consulting GmbH at the initiative of PreussenElektra

GmbH in 2018.

2 Method

2.1 Scenarios

The independent and widely accepted by industry players

“Pöyry Central Scenario” is used as the base input. It is

Pöyry’s most likely view of the development of the

electricity market and the broader economic environment

and is introduced hereafter. In this study, two scenarios for

NPPs phase-out in Germany are investigated:

pp

the “Reference” case: NPPs will shut-down according

to their latest authorized date of operation as specified

in German atomic law and shown in Figure 1. This

scenario is equal to the Pöyry Central Scenario.

pp

the “NPP Out” case: in which all seven today operating

NPPs are shut-down by the end of 2019.

The specific assumptions are described in the next

paragraphs, including the logic for the choice of 2013

as reference for the weather year.

2.1.1 Pöyry Central Scenario

Pöyry’s independent and widely accepted “Central

Scenario” is used as basis for this study. “Central” represents

a midway alternative between two more extreme

Low and High scenarios and represents Pöyry’s most likely

| | Fig. 1.

Latest NPP operation date according to German law. Source: Federal

Ministry for the Environment, Nature Protection and Nuclear Safety

(Bundesministerium für Umwelt, Naturschutz und nukleare Sicherheit).

view of the development of the electricity market and

broader economic environment. This view is based on

market expertise from all European countries, planned

and announced power plant and interconnector commissioning

and decommissioning, and projections of external

factors such as currency exchange rates, inflation, commodity

prices and electricity demand. This section provides

an overview of the core assumptions defining the

“Central Scenario”. These assumptions may be classified

under the following headings:

pp

economic assumptions

The real exchange rates are derived from projections

of nominal exchange rates and inflation. Within the

modelling, the real exchange rates are used to convert

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Real Exchange Rates

Annual Inflation Rates

US$ per £1 US$ per €1 £ per €1 US UK Eurozone

2018 1.30 1.17 0.87 2.2% 2.5% 1.5%

2019 1.35 1.23 0.88 2.2% 2.1% 1.6%

2020 1.40 1.22 0.84 2.1% 2.1% 1.8%

2021 & 2022 1.46 1.22 0.84 2.0% 2.0% 2.0%

| | Tab. 1.

Inflation and real exchange rate (2016 Money).

dollar- denominated oil and coal price projections Euros.

Table 1 shows the real exchange rates and the annual

inflation rates for the US, UK and the Eurozone that are

assumed in the modelling.

Nominal exchange rates for 2018-2020 are based on

the median composite Bloomberg forecast from up to 50

financial institutions. The farthest (2020) nominal

exchange rate is taken as the assumed long-term forecast

and kept constant for the following years. Inflation rates

for 2018–2019 are derived using the median composite

CPI forecasts from Bloomberg. In 2020 the inflation rate

trends between the 2019 value and the long-term (from

2021 onwards) assumption of 2 % in all three economic

areas. The real exchange rates therefore fluctuate until

2020 in line with the inflation rate and the nominal

exchange rate differentials that occur to 2020.

pp

generation capacity

The projected generation capacity for Germany is based on

three main components: plant which already exist or is

under construction, generic new power plant (in the longterm,

based on need and economic viability); and renewable

development (based primarily on policy and targets).

With regards to plant existing or under construction, the

status is taken from several sources including company’s

annual reports, the German federal agency for power grid

(Bundesnetzagentur) power plant list and Pöyry’s own

market intelligence. A more rapid phase-out of coal power

plants as being currently considered by the German

government in 2018 is not modelled. The construction of

new fossil generation as generic new power plant results

has a negligible impact on the rather short time period

study considered here. With regards to renewable energy

sources (RES) development the current renewable

capacity plans are considered.

pp

electricity demand

The projections for electricity demand in Germany are

produced using Pöyry’s demand model. This is an

[TWh] 2020 2021 2022

Demand DE 551.8 551.5 550.9

| | Tab. 2.

Projected annual electricity consumption.

econometric model which assumes a long-term relationship

between electricity demand and Gross Domestic

Product (GDP). The base demand in Germany for each

future year is calculated by using annual GDP growth

assumptions based on International Monetary Fund (IMF)

projections [3].

In addition to the underlying demand development due

to economic growth or recession, the demand model also

captures the impact of energy efficiency measures and the

shift of energy demand from other fuels in the transport

and heat sectors into electricity. Temperature corrections

are also applied to historical demand values to mitigate the

impact of extreme (cold or warm) weather years on future

demand projections. The reference weather year of 2013 is

selected as basis for this study. The choice of this weather

year is explained in §2.1.3. The resulting electricity

demand development (average year) can be found in

Table 2.

pp

interconnectors

Because of its geographical location within Europe, the

German power grid is interconnected with nine neighboring

countries: Austria, Czech Republic, Denmark,

France, Luxembourg, Poland, Sweden, Switzerland and

the Netherlands. The current interconnectors as well as

the projects planned for realization in time frame up to

2023 are considered in this study according to ENTSO-E

data. Regarding intra-German transmission capacities, the

assumptions of the German TSO’s on the German grid are

used in this study, which are in line with ENTSO-E assumptions

for the investigated period 2020–2022. Specifically,

the Elbe 2 grid project planned for realization in 2019 is

considered operational.

pp

fuel and CO 2 prices

Fuel and CO 2 prices are exogenous parameters inserted

into Pöyry’s power market modelling tool BID3. These

prices are determined with the help of models specific to

each commodity, expect for lignite. For lignite no model

exists as fuel costs depend only on the production costs of

this energy source. An overview of all projected fuel prices

as well as historic prices for reference can be found in

Figure 2.

pp

storage

Batteries are not modelled in this study. Although they are

being built in Germany, they are only operating in the

ancillary services market so far and there is no evidence

showing the introduction of batteries into the day-ahead

market in the modelled time frame.

| | Fig. 2.

Fuel prices overview.

Dashed line represents historical prices, solid line projections.

Sources: Historical prices – MCIS (Coal), Thompson Reuters (CO 2 ), ICIS Heren (Gas), EIA (HSFO);

Projections – Pöyry Management Consulting interpolated with forwards from API2 (Coal), Thompson

Reuters (CO 2 ), ICIS Heren (Gas), ICE (HSFO); Lignite based on fundamental production economics

2.1.2 NPPs phase-out scenarios

According to the German atomic low, the seven NPPs

operating today, with a total installed capacity of

9,509 MW, will be shut-down successively by the end of

2022 at the latest, as highlighted in Table 3. The plant

closures are modelled according to the German Atomic

law latest NPPs shut-down dates. This scenario is referred

to as “Reference” case in this study. The reference scenario

is used to benchmark the outcomes obtained from the

“NPP Out” case.

The “NPP Out” case is the alternative scenario considered.

It assumes the premature closure of all remaining

seven NPP as of 01.01.2020, as highlighted in Table 3.

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MW 2019 2020 2021 2022 2023

Reference 9,509 8,107 8,107 4,049 0

NPP Out 9,509 0 0 0 0

| | Tab. 3.

Nuclear capacity per scenario.

2.1.3 Selection of reference weather year

A reference weather year is required to model both the

demand and the generation from RES. The weather choice

is rather sensitive as it could impact substantially the study

outcomes. The weather year 2013 is selected from the

available set of weather years (2010–2014). This choice

is motivated by 2013 “average behavior”: 2013 is close

to average with regards to wholesale price, renewable

gen eration and peak prices. An overview of the two

parameters for the years under consideration can be found

in Figure 3 and Figure 4 with the deviation from average

given in Table 4. By not selecting a more extreme weather

year such as 2011 the authors aim to remain as objective

and robust as possible in the study’s outcomes.

2012 is a second candidate as both wholesale price and

renewable generation deviation are in a reasonable range.

Due to the cold winter spells end of January and early February

however, the year shows atypical price peaks and

would therefore distort the overall results too much. An

overview of the effect of cold spells on the 200 highest

prices per year can be found in Figure 4. To assess the effects

of a change in weather year on the results of this

study, a sensitivity analysis with 2012 weather year is performed.

2.2 Modelling tools

A multistage process described in this section is followed in

this work to properly assess the role of NPPs in the German

power system. The two scenarios described in §2.1 are

modelled using Pöyry’s proprietary fundamental market

modelling software BID3 combined with grid modelling

and analysis via PSS/E.

2.2.1 Power market modelling and BID3

Pöyry’s in-house, fundamental model BID3 [6] [7], models

the market dispatch of all generation facilities in Europe.

BID3 can model the behavior of individual power plants of

all fuel types as well as renewable generators. It simulates

all 8760 hours per year, generating hourly wholesale

prices. An overview is shown in Figure 5.

The output of all generators is jointly optimized for

economic costs for each hour of the modelled time period.

The result of the process is a fundamental view of what the

market prices, power plant dispatch, cross-zonal interconnection

flows and total cost of generation in each

scenario will be on an hourly resolution. In this modelling

process, price zones are optimized jointly such that for

Germany the entire price zone is optimized disregarding

any internal transmission capacity restrictions while for

instance Sweden is split into four price zones. All zones are

optimized simultaneously and so is the market flow between

them. All evaluations are realized at the European scale.

2.2.2 System modelling and PPS/E

PSS/E is a transmission system planning and analysis

software developed by Siemens Power Technologies International

(Siemens PTI). The Siemens PTI PSS/E software

product is an integrated program providing power flow,

short circuit and dynamic simulation. In this study PSS/E is

applied to the European Network of Transmission System

| | Fig. 3.

Weather years 2010–2014 wholesale price and RES generation.

| | Fig. 4.

Peak Prices in Weather Years 2010 – 2014

[EUR/MWh].

| | Fig. 5.

Pöyry BID3 Overview.

Weather

year

Wholesale

price

Operators for Electricity (ENTSO-E) high voltage system

data of the Central European synchronous area. The software

simulates substations as nodes to which power lines,

loads, generators, and auxiliary devices such as shunt reactors/capacitors

are connected. For the load flow calculations

performed in this study, power lines are modelled as

impedances with loss-causing resistance and power-factor

altering reactance. Generators are modelled by providing

maximum and minimum real power deliverable as well as

available range in terms of reactive power. The maximum

real power is provided by BID3 and is a result of market

modelling. Loads are modelled as constant active and

reactive power based on the ENTSO-E Ten-Year Network

Development Plan 2016 (TYNDP2016) dataset. Loads and

generators connected below 220 kV voltage level are aggregated

to loads and/or generators at the buses where they

are connected to the high voltage grid. Flows to countries

outside the synchronous areas, i.e. through DC lines, are

set as fixed flows using hourly flow data from BID3.

Renewable

Generation

2010 +9.9 % -6.5 %

2011 -3.5 % +7.7 %

2012 +4.2 % +2.2 %

2013 -1.6 % -2.7 %

2014 +9.0 % -0.8 %

| | Tab. 4.

Deviation from average of the weather years

2010–2014.

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| | Fig. 6.

Iteration between BID3 and PSS/E.

With this setup, the Central European synchronous

area can be modelled in its entirety. By altering the power

output of the plants in Germany, PSS/E can reduce lineloadings

in all lines to below 70 % of maximum capacity

with a 10 % relaxation factor. It means PSS/E aims at

clearing congestion with 70 % nominal derating factor

but, if that is not possible, loads up to 80 % are allowed. As

the result some lines are loaded between 70 % and 80 %.

This alteration is done with the objective of changing plant

outputs to a minimal level, i.e. with limiting disturbance of

generation schedule. PSS/E however does not consider

cost of generation as a parameter when altering generation

levels and therefore creates a non-optimal solution from

an economic point of view. 70–80 % line loading is used as

a reasonable proxy for fulfilling the n-1 criterion since

contingency analyses, requiring dynamic analysis, are not

performed in this study. To receive a dispatch that is both,

economically optimized and preventing line overloading, a

coupling between BID3 and PSS/E is implemented.

2.2.3 Iteration between BID3 and PSS/E

BID3 and PSS/E have complementary strengths with BID3

focusing on market dispatch and PSS/E on system stability.

In combination the two software can form a full redispatch

model on an hourly level.

As starting point, the market dispatch is calculated in

BID3 where each market zone is represented as one

node with transmission constraints of interconnectors as

boundaries between them. Within the software, the power

plants are then activated such that all loads can be served

at minimum total cost. From this calculation, a dispatching

schedule for all power plants is derived which can serve as

input for the next phase of the computation.

Simultaneously, the ENTSO-E grid data is loaded into

PSS/E and a run based on reference dispatching schedules

from ENTSO-E is created. The dispatch results and loads

from BID3 then replace the original data and the system is

rerun. With the market dispatch given, several lines in the

system are overloaded. Overloading in the German system

are resolved using PSS/E corrective action as described in

§2.2.2. Since PSS/E does not economically optimize its

redispatch, an interface back to BID3 is required.

This interface is implemented by splitting Germany into

nine virtual zones set such that critical lines cross zonal

borders and setting cross-zonal transmission limits. These

transmission limits are then based on the cross-zonal

transmission flow in PSS/E for all 8760 hours of the year

after the corrective action analysis where line overloading

is reduced. By then performing the market dispatch on a

zonal basis, the BID3 dispatch is forced to respect major

line capacity restrictions.

As BID3 however only “sees” the transmission constraints

between the zones and not within them, PSS/E

and BID3 need to be run iteratively until the market

dispatch satisfies the systems constraints. The iteration

thus consists of PSS/E generating maximum flow

constraints between the zones, BID3 running with these

constraints and deriving a dispatching schedule which

PSS/E again adapts resulting in new flow constraints. The

iteration is performed five times until the market redispatch

no longer causes any significant overloading. An

overview of the process can be seen in Figure 6.

2.3 Metrics

The main quantified indicators highlighting the study

outcomes are described hereafter.

2.3.1 Socio-economic welfare

The socio-economic welfare is defined as a measure of the

economic impact of the power system to the society. In this

study, it refers to the amount of cost or gains incurred by

producers, consumers and through congestion in interconnectors

between countries. The three components of

the socio-economic welfare have been assessed:

pp

Producer surplus is the gross margin achieved by

producers. It is defined as the value of electricity sold

minus the variable costs of generation (mainly fuel and

CO 2 ).

Producer surplus = total generation * wholesale price –

generation cost

pp

Consumer surplus is the value of uninterrupted

electricity supply to consumers. Consumer surplus is

defined as the difference between value of lost load and

wholesale price.

Consumer surplus = (Value lost load – wholesale price) *

total generation

pp

Congestion rent is the cost of utilizing an interconnector.

It is defined as the costs saving resulting of

energy flow across the border multiplied by the amount

of energy transferred across the border.

The investment and building costs of new generation

capacity such as gas plant, RES or interconnections are not

considered in this study. However, it is important to

mention that part or all of the producer surplus is needed

to cover fixed costs and therefore avoid the impression that

any positive surplus represents a form of super normal

profits. The approach of focusing only the variable costs is

motivated by the scenarios looked at: only the NPPs

installed capacity varies between both scenarios as the

short time frame considered would not permit the building

of new generation and grid capacity in the “NPP Out”

scenario.

2.3.2 Wholesale prices

The wholesale price is a combination of short-run marginal

costs (system marginal price) and a premium during

periods of a tight system (scarcity rent), although in the

last decade the incidence of such premiums at all, let alone

of any significant size, has been very infrequent. Both

components are added to form the wholesale price.

In the real world, market participants submit bids

which are sorted to construct the so-called “merit order”.

These bids are largely reflective of the short-term marginal

costs of a plant such as fuel cost and machine wear. This is

modelled as the system marginal price (SMP).

As the more expensive plants are often price setting and

would thus not generate a profit, these plants need to

bid above their SMP to cover their fixed costs such as

personnel, land lease, return on capital employed, etc.

This is modelled as scarcity rent (SR).

The SMP is based on short-term costs and reflects the

difference between staying idle and generating power for

the most expensive plant in that hour. Modelling of the

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system marginal price is very similar to the merit-order

used in power exchanges. The power plants are ordered by

marginal price and plants are activated up until the current

demand has been satisfied. Power plants have restraints on

them such as minimum on- and off-times causing slight

distortions in the merit order. BID3 optimizes the system

such that overall costs of generation are the lowest. The

system marginal price is therefore the result of the

economic optimization and in principle comparable to the

merit-order price if every power plant would only bid its

short-term costs.

Scarcity rent is used to replicate strategic bidding at

tight system status where suppliers bid above their shortrun

marginal costs. In BID3 all plants bid their short-run

marginal costs (SRMC). As peak power plants are often

price-setting, they would make little profit and are unable

to cover long-run marginal costs (LRMC). Without capacity

payments peak plants in the real world thus usually bid

above their SRMC.

2.3.3 CO 2 emissions

The CO 2 emissions of every single plant are modelled

according to their respective generation. The CO 2

emissions of Germany and Europe result from the aggregation

of CO 2 emissions from all respective plants. Table 5

gives an overview of CO 2 emissions per fuel types of power

plants as used in BID3.

The impact on CO 2 price (€/tCO 2 ) of the scenario

considered is not systematically evaluated. A sensitivity

study is performed to justify this approach. It should be

noted that, due to the emissions cap of the ETS system and

changes in the carbon price needed to fulfil the cap,

European CO 2 emissions might adapt in the long run,

beyond the timeframe of 2020–2022.

Fuel type CO 2 emissions [t CO 2 /MWh therm ]

Biomass 0

Coal 0.322

Gas 0.182

Gasoil 0.251

Lignite 0.354

Nuclear 0

Peat 0.420

RES 0

| | Tab. 5.

CO 2 emissions per fuel type.

2.3.4 System capacity margin

Capacity margin is a measure of the tightness of the system

and is analyzed to assess the adequacy of the system. The

capacity margin corresponds to the available resources in

generation and interconnection net the demand, in other

words the available resource capacity that is not needed to

meet demand. The capacity margin is measured in every

hour of the simulation, and the minimum capacity margin

can be used as an indication of the generation adequacy of

the system.

good proxy to estimate redispatch costs. Those costs focus

on thermal power plants generation costs.

2.3.6 Grid losses

The energy efficiency benefit of a transmission/generation

project is measured through the reduction of thermal

losses in the grid. Transmission system loss is calculated

by multiplying the square of line loadings with the line

resistance. As implied form the loss formula, it depends on

the loading of lines in a system and the resistance of each

line. As a result, system losses are dependent on relative

location of system load and generation. Even if the location

and amount of system load remains the same, system loss

can vary depending on the generation dispatch scenario.

This effect is measured by network studies. To calculate the

difference in transmission losses in Germany (in units of

energy [GWh]) attributable to NPPs in Germany, the losses

are computed in two different simulations with the help of

network studies in PSS/E. Losses in 400 kV and 220 kV

transmission grid are included in the study.

3 Results

The study shows several impacts from an accelerated

closure of nuclear power plants in Germany. These can be

split into effects on the market side and effects on the

network side. Comparing the “Reference” and “NPP Out”

scenarios, the following effects on the market side are

obtained:

pp

Decreased social welfare of ~2 billion EUR (bEUR) per

year. Electricity producers gain up to 1.9 bEUR, while

consumers lose 4.3 bEUR per year, totalling in a loss of

social welfare of 5.8 bEUR within 3 years;

pp

Increased wholesale prices in the range of 4–7 EUR/

MWh. Consumer prices will be affected somewhat less

as higher wholesale prices decrease the EEG levy;

pp

Increased power-related CO 2 emissions in Germany by

up to 17.1 million tons per year and in Europe by

36.2 million tons per year, totaling in additional CO 2

emissions of 41.8 million tons in Germany and

89.8 million tons in Europe within 3 years;

pp

Reduced capacity margins of up to 1.46 GW (amounting

to a 25 % reduction), implying a reduced security of

supply;

pp

Reduced power exports from Germany by 20–40 TWh

per year.

After including network constraints, the main results

from the market study are confirmed with the following

highlights:

pp

Increased north to south flows in Germany by up to

4.7 TWh per year in specific regions.

The effects on the network side are:

pp

Increased European redispatch costs by 78 mEUR

between 2020 and 2022;

pp

Increased transmission losses by 8–10 % in 2020 and

2021, resulting in additional costs of about 35 mEUR,

due to an increased need for energy transmission.

Increase by 2 % in 2022 lower due to more favorable

siting of remaining NPPs.

Those results are detailed in the next sections.

FEATURE | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 75

2.3.5 Redispatch costs

Redispatch costs are evaluated as the difference of generation

costs between the BID3 initial optimization and the

converged coupled BID3-PSS/E simulation. It is evaluated

on an hourly basis at the European level. The power mix

obtained after the BID3-PSS/E iteration reflects the

physical constraints of power transmission and as such is a

3.1 Socio-economic welfare

Phasing out NPPs early 2020 leads to annual losses of socioeconomic

welfare in Germany of 1.4–2.4 bEUR totaling in

an overall sum of 5.8 bEUR in the time frame 2020–2022.

The nuclear phase out scenario is analyzed with regards

to changes in socio economic welfare compared to “Reference”

case. The results are highlighted in Figure 7.

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| | Fig. 8.

Average annual wholesale prices.

| | Fig. 7.

Socio-economic welfare, difference to “base” case.

Producer surplus and consumer surplus develop differently

after decommissioning of NPPs. Surplus is partly

redistributed from consumers to producers, with producer

surplus increasing due to higher wholesale prices by

1.0–1.9 bEUR/a between 2020 and 2022 despite the loss

of rent from closed nuclear plants. The benefits in producer

surplus are outweighed by losses in consumer

€/MWh Reference NPP Out

Scarcity Rent SMP Scarcity Rent SMP

2020 1.97 34.17 3.48 38.33

2021 3.88 35.87 6.78 39.64

2022 7.28 38.46 9.44 40.04

| | Tab. 6.

Average scarcity rent and system marginal price.

surplus more than twice the benefit gained. The loss of

consumer surplus per year is ranging from 2.4–4.3 bEUR/a,

summing up to consumer welfare reduced by 10.4 bEUR

over the course of the three analysed years. Differences in

congestion rent are negligible compared to differences in

consumer and producer surplus.

3.2 Wholesale Prices

The development of average annual wholesale prices in

the time frame 2018-2022 is shown in Figure 8. Prices

show an upward movement from 2019 onwards in all three

scenarios and rise from 32.7 EUR/MWh in 2019 to

45.8 EUR/MWh in 2022 in the Base Case scenario. The

increase in wholesale prices is more significant with less

capacity from nuclear power plants and the difference

between the two scenarios is largest in the years 2020 and

2021. The NPP Out scenario shows prices 4–7 EUR/MWh

higher than the Base Case with a maximum difference in

2021 at 46.4 EUR/MWh compared to 39.8 EUR/MWh in

Base Case in that year.

The components of the wholesale price – scarcity rent

and system marginal price – are depicted in Table 6 and

Figure 9. The scarcity rent is on a low level in 2018 and

2019, slightly larger than 1 EUR/MWh. As the system gets

tighter in the following years, scarcity rent rises considerably

to levels above 7 EUR/MWh in 2022 in both scenarios,

when nuclear capacity is also strongly reduced in Base

Case. The difference in scarcity rent between NPP Out and

Base Case amounts to 1.5–2.9 EUR/MWh in the period

2020–2022.

System marginal price is at 31.4 EUR/MWh in 2019. It

rises noticeably in subsequent years to 38.5 EUR/MWh in

2022 in “Base” case and 40.0 EUR/MWh in “NPP Out”

case. Differences between NPP Out and Base Case total up

to 4.2 EUR/MWh in 2020 and 2021, where less nuclear

power plant capacity leads to a shift in the supply curve

and thus a higher system marginal price.

| | Fig. 9.

Average scarcity rent and system marginal price.

| | Fig. 10.

CO 2 emissions in Germany and Europe.

1. Source: Estimation by Federal Environment Agency 2. Source: Federal Environment Agency

3.3 CO 2 emissions

The development of power related CO 2 emissions is

illustrated for both scenarios in Figure 10. German and

European CO 2 emissions show a downward trend.

How ever, the trend of diminishing CO 2 emissions in

Europe is dampened by a shutdown of nuclear power

plants. Increased generation of CCGTs, coal and lignite in

NPP Out and Reduced NPP raise power related CO 2

emissions in Germany and Europe between 2020 and

2022. A complete premature nuclear power plant phase

out leads to higher CO 2 emissions in Germany of 8.2–

17.1 million tons per year (mt/a), amounting to 41.8 mt in

the observed period. European emissions rise by 17.7–

36.2 mt/a, totaling in 89.8 mt. The difference is largest in

the years 2020 and 2021, when the difference in nuclear

capacities is largest compared to Base Case. Around 50 %

of the additional European emissions arise in Germany.

The yearly increased emissions in Germany are equivalent

to total emission of the city of Hamburg every year.

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atw Vol. 64 (2019) | Issue 2 ı February

| | Fig. 11.

Minimum capacity margin in Germany.

Source BNetzA: Feststellung des Bedarfs an Netzreserve für den Winter

2018/2019 sowie das Jahr 2020/2021

It should be noted that, due to the emissions cap of the

ETS system and changes in the carbon price needed to

fulfil the cap, European CO 2 emissions might reduce again

in the long run, reducing the long-run CO 2 effect of the

premature nuclear shut down.

3.4 System capacity margin

The minimum capacity margins decrease by 1.46 GW at

most in 2020 in the “NPP Out” case compared to “Base”

case. Capacity margins shown in Figure 11 are margins in

the tightest hour of the analysis. This minimum capacity

margin declines from 6.9 GW in 2019 to 3.0 GW in 2022

due to an ongoing phase out of nuclear, coal and lignite

capacity. In the “NPP Out” case NPP, capacity margins are

reduced even further because of the premature nuclear

phase out. The difference totals up to 1.46 GW (amounting

to a 25 % reduction) in 2020 in NPP Out, implying a

reduced security of supply. As outages are not considered

here, a slightly positive capacity margin signals a certain

risk of demand curtailment. For comparison, the BNetzA

grid reserve plans are provided which are capacities meant

for ensuring successful security of supply even in stressful

situations. As the plants active in the reserve are not

considered in the model, their capacities (2020: 4.1 GW,

2021: 3.3 GW, 2022: 2.8 GW) have to be considered in

addition to the results provided.

A sensitivity study is performed for the weather year

considering 2012 as reference year instead of 2013. The

atypical climate in winter results in a reduction of

minimum capacity margins by ~3 GW and an average

increase in wholesale prices by 5 EUR/MWh out of which

~3 are attributable to scarcity rent and the remaining ~2

to increase in SMP due to moving higher up in the merit

order. This decreases the socio-economic welfare further

by 0.2–0.4 bEUR/a.

3.5 Redisptach Costs

The thermal redispatch costs increase in the “NPP Out”

case relative to the “Base” Case. Those costs increase by

26 million EUR in 2020, 11 million EUR in 2021 and

41 million EUR in 2022. In parallel the generation from

renewable energy sources first increases before decreasing

in 2022 due to the early nuclear phase-out. In total the

costs decrease by 219 million € over the period 2020–2022,

remaining minor compared to the above-stated loss of

social welfare.

Replacing RES is the most expensive form of redispatch

as generators with marginal costs of 0 are replaced with

relatively expensive gas plants. Especially in scenarios

with high wind feed-in in the north of Germany and low

demand in the area, the grid often becomes overloaded

and generation must be redispatched from north to south.

The reason for overloading can be twofold: One possibility

is that the distribution system is overloaded and the power

generated cannot be evacuated to the next transmission

substation. This is a typical issue with small generators

such as wind turbines which are connected to the lower

voltage levels. Since this study focusses on the high voltage

grid only, those constraints are not evaluated. The second

reason for overloading is bottlenecks in the transmission

system where especially north-south lines are frequently

overloaded.

As redispatch in this study is performed at the European

scale, instead of considering the German context only, the

redispatch results are also given for the entirety of Europe.

As Germany is the origin of the redispatch need, it is

reasonable to assume that Germany would have to bear

the cost of such grid stability measures.

3.6 Grid losses

System loss can increase or decrease when NPPs are out of

operation compared to the base case, depending of the

hour considered. On a yearly basis for both year 2020 and

2021, the system transmission energy loss increases by

about 10 % when the NPPs are taken out of operation

compared to Base Case. This represents an increase of

associated costs by close to 35 million euros. For year

2022, the transmission loss increases to 2 % when the

remaining NPPs are out of operation compared to the base

case. The reason for the lower increase in losses in year

2022 compared to other two years is that in year 2022

there are less NPP in Base Case.

3.7 Additional results

The coupled BID3 and PSSE/E analysis enables to extract

further results from the study. A few are presented hereafter.

pp

Power flows: a closer analysis of generation and flow

shifts is performed for the “NPP Out” case compared to

“Base” case in the years 2020–2022 after redispatch

due to grid constraints. The lost generation capacity

from a NPP shut down leads to increased flows from

north to south. The maximum change in flows observed

is an increased flow of 4.7 TWh.

pp

Electricity exports: early electricity exports from

Germany show a decreasing trend after 2019. In Base

Case, exports drop from 56.7 TWh per year to 25.9 TWh

per year in 2022. Reduced generation from a nuclear

phase-out leads to an even sharper reduction of yearly

electricity exports from Germany. In 2021, annual

exports reduce by almost 90 % in NPP Out to a level of

4.9 TWh, compared to Base Case with 40.2 TWh. These

show a very similar profile in all scenarios with shifts of

~1–3 TWh/month between scenarios. The shifts are

slightly lower in the summer months, when nuclear

availability is typically lower.

4 Discussion

The results obtained from the market study using BID3 are

derived using a well-established modelling practice giving

confidence on the outcomes. The outcomes show negative

consequences from a socio-economic perspective of an

early NPPs shut-down early 2020. The limit of such results

derived with market analysis only is the difference between

the ideal market approach as simulated by BID3 and the

FEATURE | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 77

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atw Vol. 64 (2019) | Issue 2 ı February

FEATURE | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 78

reality of power flows and power grid limitations. This

study tackles this limitation by introducing a coupled

market and grid system analysis.

This innovative method enables a good estimation of

grid management measures volumes and costs required to

realize an optimized power mix. However, it contains some

simplification worth mentioning. First, the evaluation is

performed at the European level as a proxy for the German

grid management measures. Since the origin of the effect

– early closure of NPPs – would occur in Germany, this

approximation seems realistic. Second, real life grid

management measures and redispatch contain some

meta-heuristic characteristics: at the level of transmission

system operators (TSOs), responsible to ensure the

stability of the power grid, human-based decisions requiring

engineering judgment are often made. This aspect

makes the evaluation of redispatch volume and costs via a

modelling tool particularly difficult. To quantify the associated

bias, a possible way forward would be an analysis of

grid management measures and costs in previous years

with the couple BID3 – PSS/E approach.

5 Conclusion

This study investigates the effects of nuclear power plants

(NPPs) premature phase-out early 2020 on the German

power system for the years 2020–2022 by carrying out a

model-based market analysis in iterative conjunction with

a power grid system simulation.

Results are generated according to market dispatch

which consequently are adapted to adhere to network

constraints through grid management measures. According

to market dispatch analysis, the early closure of NPPs

early 2020 would reduce the social welfare by ~2 billion

EUR per year. This loss is carried by consumers. Producers

would gain as their higher cost of generation are overcompensated

by the increased wholesale price. The increase in

wholesale prices is in the range of 4–7 EUR/MWh which

feeds through to large consumers directly and is slightly

reduced to a lower EEG levy for smaller consumers.

Capacity margins are reduced by up to ~25 % (1.5 GW)

without NPPs from early 2020 onwards. Those results are

obtained with simulations performed using the reference

weather year of 2013. The choice of that specific weather

year is made to remain as objective as possible since 2013

had average temperatures and RES generation. Some

effects are worsened considering other weather year with

more extreme behavior. A sensitivity study is performed

with the weather 2012 where the cold spell already puts

the system under further stress. CO 2 emissions are also

adversely affected by a premature nuclear phase-out with

an additional 89.9 million tons of CO 2 emitted additionally

over the three years.

With regards to power grid effects with and without

NPPs in the German system, diverging effects occur. The

thermal redispatch costs increase without NPPs by

78 million EUR over the period 2020-2022. In parallel the

generation from renewable energy sources first increases

before decreasing in 2022. In total the grid management

costs decrease by 219 million € over the period 2020–2022,

remaining minor compared to the above-stated loss of

social welfare. The system is stressed additionally by the

departure of NPPs as transmission losses increase (2–10 %

per year) and north to south flows increase by up to

4.7 TWh per year in specific regions.

The study reviewed solely the effects of an accelerated

closure of NPPs early 2020. An extension of nuclear power

plant lifetime beyond the current phase-out timeline

stated in the nuclear power law of 2011 is out of the scope

of this work.

Acknowledgement

The authors would like to acknowledge Pöyry Management

Consulting GmbH and PreussenElektra GmbH efforts

to enable this work. A special thank goes to the ENTSO-E

organization and the German TSO Tennet TSO GmbH,

Amprion GmbH, TransnetBW GmbH, 50Hertz Transmission

GmbH, for their support.

References

[1] O. Renn and JP Marhsall. Coal, nuclear and renewable energy policies in Germany: From the

1950s to the “Energiewende”. Energy Policy, volume 99 p224-232, 2016.

[2] OECD/Nuclear Energy Agency. The Full Costs of Electricity Provision. NEA report No. 7441, 2018.

[3] International Monetary Fund (IMF), World Economic Outlook, April 2017.

[4] Backcasting the GB Balancing Mechanism with BID3. O. Stoica and T. Poffley. Poyry and national

Grid join report, Sept 2017.

[5] https://www.siemens.com/global/en/home/products/energy/services/transmissiondistribution-smart-grid/consulting-and-planning/pss-software/pss-e.html

[6] Audit of the BID3 Pan European Market Model for National Grid. K. Bell and I. Stafell, National

Grid, Oct 2016.

[7] Netzenwicklungsplan Strom, 4 TSOs, Marktmodell BID3 (Kapitel 3.1), 2015.

Authors

Denis Janin

Volker Raffel

PreussenElektra GmbH

Dr. Eckart Lindwedel

Pöyry Management Consulting (Deutschland) GmbH

Prof. Graham Weale

Ruhr Universität Bochum

James Cox

Pöyry Management Consulting (UK) Ltd

Geir Bronmo

Pöyry Norway AS

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atw Vol. 64 (2019) | Issue 2 ı February

Serial | Major Trends in Energy Policy and Nuclear Power

Wind Energy in Germany and Europe

Status, potentials and challenges for baseload application:

European Situation in 2017

Thomas Linnemann and Guido S. Vallana

Introduction Wind power is a cornerstone of rebuilding the electricity supply system completely into a renewable

system, in Germany referred to as “Energiewende” (i. e. energy transition). Wind power is scalable, but as intermittent

renewable energy can only supply electrical power at any time reliably (security of supply) in conjunction with

dispatchable backup systems. This fact has been shown in the first part of the VGB Wind Study, dealing with operating

experience of wind turbines in Germany from 2010 to 2016 [1],[2]. This study states among other things that despite

vigorous expansion of on- and offshore wind power to about 50,000 MW (92 % onshore, 8 % offshore) at year-end 2016

and contrary to the intuitive assumption that widespread distribution of about 28,000 wind turbines, hereinafter

referred to as German wind fleet, should lead to balanced aggregate power output, no increase in annual minimum

power output has been detected since 2010, each of which accounted for less than 1 % of the relevant nominal capacity.

The annual minimum power output reflects the permanently

available aggregate power output (secured capacity) of the

whole German wind fleet by which conventional power plant

capacity can be reduced on a permanent basis. Or in other

words: In every year since 2010 there was always at least one

quarter of an hour in which more than 99 % of the nominal

capacity of the German wind fleet was not avail able and, for

all practical purposes, a requirement for 100 % dispatchable

backup capacity prevailed, although its nominal capacity

had almost doubled at the same time. Intuitive expectations

that electricity generation from widespread wind turbines

would be smoothed to an extent which in turn would allow

the same extent of dispatchable backup capacity to be

dispensed with has therefore not been fulfilled.

Dispatchable backup capacity is essentially necessary

to maintain a permanently stable balance between

temporal variations of outputs from wind turbines and

other power plants fed into the power grid and consumerdriven

temporal demand variations extracting power from

the grid (frequency regulation).

To maintain power grid stability, ancillary services such

as primary control capacity or large rotational inertia are

also necessary to limit widely oscillating frequency

deviations (grid oscillations) − properties that con ventional

power plants with their turbo generators per se possess [3],

but which must be provided separately as additional ancillary

services in case of a largely renewable power supply

system based on wind and solar energy ( photovoltaics).

For grid stability, a secured capacity of power plants

including grid reserve and standby capacities for backup

purposes of currently about 84,000 MW is required in

Germany at the time of annual peak load occurring

between 17:30 and 19:30 during the period from November

to February [4].

If electricity generation from wind power is further

expanded in line with the objectives of the German federal

government, the nominal capacity of the German wind

fleet should exceed this secured capacity of power plants in

several years’ time. From that point on, the dispatchable

backup capacity to be maintained would have to be capped

at about the level of this secured capacity of power plants

which is sufficient for grid stability reasons.

Solar energy (photovoltaics) as a further scalable and

politically designated cornerstone of the German Energiewende

is always 100 % unavailable during the times of

year and day relevant for the annual peak load, as well as

year-round at night, and therefore per se cannot make any

contribution to the secured power plant capacity [4].

At year-end 2017, almost 1.7 million photovoltaic

systems with around 42,400 MW nominal capacity (peak)

were installed throughout Germany, supplying 40 TWh

of electricity year-round [5]. By comparison, net power

consumption amounted to around 540 TWh. This amount

does not include the balance of electricity imports and

electricity exports of almost 55 TWh [6], the auxiliary

electric load of power plants of about 34 TWh [7] or grid

losses at all voltage levels of around 26 TWh [8]. Photovoltaics

therefore contributed around 7.4 % towards

meeting the domestic net power requirement.

Analyses of quarter-hourly time series of power output

from wind turbines and photovoltaic systems in Germany

over several years, scaled up to a nominal capacity of an

average 330,000 MW to obtain 500 TWh electricity from

these two intermittent renewable energy systems (iRES) per

year, lead to a continued high need for dispatchable backup

capacity of 89 % of the annual peak load [9],[10]. This average

iRES nominal capacity includes 51 % of onshore wind

power, 14 % of offshore wind power and 36 % of photovoltaic

systems. The annual electrical energy amount of

500 TWh reflects Germany’s net electricity consumption

plus grid losses minus predictable renewable energy systems

(RES) such as run-of-river and pumped storage power

plants, biomass and geothermal power plants.

The saving in backup capacity of 11 % of the annual

peak load under these conditions is essentially attributable

to the regular night-time load reduction, as high backup

capacities are seldom necessary during the daytime with

electricity generation from solar power. From 2015 to

2017, an average 13 % of the annual hours in which iRES

power outputs of less than 10 % of the iRES nominal

capacity arose were accounted for by daytime hours

between 08:00 and 16:00.

As, at around 130 TWh, slightly more than one quarter

of the iRES annual electric energy would occur at times of

low demand (surplus) and therefore not be directly usable,

the dispatchable backup system would have to provide the

equivalent of these surpluses temporally delayed with a

very low capacity factor of a maximum 20 %.

From one year to the next, weather-related fluctuations

of iRES annual electric energy of at least ±15 % would

have to be factored in [9], with repercussions on the

backup capacity in case of continued efforts to maintain

the current high level of security of supply.

According to annual outage and availability statistics

compiled by the Forum Network Technology/Network

Operation of VDE as German Association for Electrical,

Part 1 *

*) Part 2

to be published

in atw 3 (2019)

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Wind Energy in Germany and Europe ı Thomas Linnemann and Guido S. Vallana


atw Vol. 64 (2019) | Issue 2 ı February

SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 80

Power in MW

65,000

60,000

55,000

50,000

45,000

40,000

35,000

30,000

25,000

20,000

15,000

10,000

5,000

0

WT: Wind turbines

Electronic and Information Technologies, reliability of the

power grid in Germany, reflected by an outage duration of

11.5 minutes per electricity customer in 2016, remains

extremely high [11]. On this basis, the level of security of

supply of end consumers in Germany averaged 99.998 %.

These results are based on the optimal mix of wind

power and photovoltaics providing 100 % of the net annual

electricity consumption of 500 TWh, in which the annual

electric energy to be supplied by the backup system

becomes minimal. Under these conditions the backup

system would have to cover slightly more than one quarter

of the annual electric energy, namely 130 TWh, photovoltaics

around one fifth and wind power the remainder.

In the case of non-dissipative energy storage with unlimited

power input and power output capped at nine tenths

of the annual peak load, iRES production surpluses of

130 TWh on average would be sufficient as backup.

If the previous review is widened to encompass eight

[12] or 27 European countries [13], two limiting cases can

be distinguished:

pp

In the first limiting case without interconnectors, a

separate country analysis is sufficient, and each

European country has to provide an average 23 % [12]

or 24 % [13] of its iRES annual electricity generation

by means of a national dispatchable backup system.

This theoretical limit implies sufficient transmission

capacities within the country in each transport

direction. Such national copper plates are certainly not

realistic in any case.

pp

In the second (theoretical) case, additionally characterised

by the optimum European interconnection via

interconnectors with infinitely large transmission

capacities without transmission losses, this average

falls to 16 % [12] or 15 % [13].

The annual backup energy reduction from 23 % to 16 %

[12] or 24 % to 15 % [13] reflects the maximum benefit

that can be achieved with an optimally interconnected

Europe. The required backup capacity would be reduced

further by an average 13 % of the annual peak load in this

case [12]. For Germany, a total reduction in backup

capacity by about one quarter of the annual peak load

could then be expected. About 46 % of this reduction

would be attributable to the domestic effect and 54 % to

Europe’s effect.

For the interconnectors in an optimally interconnected

Europe, transmission capacities of 831,000 MW would

Number of wind turbines (end of year, rounded)

26,903

21,678

4,100

28,712

22,870

30,979

24,086

33,477

26,268

Year

38,614

29,344

5,066 5,225 5,388 5,840

44,580

32,926

Quarter-hourly resolution

21,600 WT 22,300 WT 23,000 WT 23,800 WT 25,100 WT 26,800 WT 28,200 WT 29,800 WT

Nominal power PN

Maximum PMax

49,592

33,834

Arithmetic mean Pµ

8,851 8,769

56,164

39,408

11,720

Minimum PMin

113 88 115 121 24 105 128 158

2010 2011 2012 2013 2014 2015 2016 2017

Sources: BMWi, BWE, German TSO

| | Fig. 1.

Figures on electricity generation from wind power in Germany since 2010 with the year-end

nominal capacity P N of the German wind fleet, the annual maximum P Max and the annual

minimum P Min as well as the mean value P µ of the power time series.

have to be established, corresponding to twelve times the

European interconnector capacity in 2011. Meanwhile, the

benefit of interconnecting Europe would already approach

97 % of the maximum with six-fold interconnector capacity

compared to 2011 [13].

Attention should be drawn to the fact that Wagner’s

calculations [12] are based on time series for aggregate

power output from wind power and photovoltaics in 2012

available on the internet as transparency data from transmission

system operators, whilst Rodriguez et al. [13] use

weather data from 2000 to 2007 as input for their model

calculations on iRES-based electricity generation.

Therefore, even with quadrupled iRES nominal capacity

compared with the current level in an optimally interconnected

Europe, a comparatively small saving in

dispatchable backup capacity and low capacity factors of

the backup system, for instance of Germany, are to be

expected, with repercussions on its profitability.

Review of electricity generation

from wind power in Germany since 2010

In the first part of the VGB Wind Study [1] electricity generation

from the German wind fleet from 2010 to 2016 has

been analysed. Meanwhile operating data for one

additional year are available and enable an update before

Europe is moved into the spotlight.

In 2017, the nominal capacity of the German wind fleet

increased by a further 12 % year-on-year to roughly

56,000 MW (Figure 1), some 90 % of which was accounted

for by onshore wind power and 10 % by offshore wind

power.

The German wind fleet comprised a total of almost

30,000 turbines at the end of the year. This corresponds to

6 % growth compared with the previous year.

The annual peak power output P Max reached a new alltime

high of almost 40,000 MW in 2017. This all-time high

occurred on 28 October 2017 between 18:15 and 18:30.

Note: All times in connection with quarter-hourly or

hourly data are stated in coordinated universal time (UTC)

in this study.

In the afternoon and evening of that day in October, the

low-pressure system “Herwart” swept across the north and

east of Germany with severe to hurricane-like storm-force

gusts and gale-force winds, caused gusts of up to hurricane

force in Denmark, Poland and the Czech Republic and led

to extremely high power output from wind turbines there

as well.

Due to high, but not too high wind speeds prevailing

over large parts of Germany and its neighbours at times on

that October day, around 70 % of the wind turbines in

Germany fed their nominal capacity into the power grid.

Note: Wind turbines automatically switch off at wind

speeds of around 25 m/s according to preventive measures

(storm deactivation).

Similarly high aggregate power output also occurred in

Germany on 18 March 2017 with the low-pressure system

“Eckart”, which brought severe storm-force gusts to Berlin

and Brandenburg.

Even without these spring and autumn storms, 2017

was an extremely windy year. The mean power output P µ

of the German wind fleet as measure of electrical energy

supplied annually rose by 34 % year-on-year to 11,720 MW.

This corresponds to an annual electric energy of 103 TWh.

Wind power thus for the first time breached the annual

generation threshold of 100 TWh.

The annual minimum power output P Min of 158 MW

occurred on 6 July 2017 between 07:15 and 07:30 and

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Wind Energy in Germany and Europe ı Thomas Linnemann and Guido S. Vallana


atw Vol. 64 (2019) | Issue 2 ı February

remained − as in the previous seven years − significantly

below 1 % of the nominal capacity P N at year-end.

Comparatively low German wind fleet power outputs

over several consecutive hours of up to 1 % of the nominal

capacity or nearly 562 MW were recorded in January,

June, July, August, September and October, and therefore

in six months of the high-wind year 2017.

Note: A minimum power output of the German wind

fleet of 229 MW has been recorded in 2018, with a nominal

capacity of around 59,000 MW (90 % onshore, 10 %

offshore).

As low power output can occur during both day and

night, the matter of future security of supply cannot be

resolved by expanding electricity generation from photovoltaics.

In their energy performance reports, the German transmission

system operators point out that it is difficult to

make reliable statements about possible unavailable

capacity of volatile renewable energy systems at the time

of the annual peak load. In their responsibility for safe grid

operation they call for such supply-dependent volatile

capacity to be available to at least 99 % of a year in order to

be considered as secured capacity [4].

To this end they regularly evaluate historical time series

of iRES normalised power output in relation to the nominal

capacity as ordered annual load duration curves. From

these curves they derive an aggegate secured capacity for

the German wind fleet of a maximum 1 % of the nominal

capacity, and stress even a restriction to the winter months

would indicate no significant change in this result [4].

In view of the fact that the annual minima of the

German wind fleet power output have all even been found

to amount to less than 0.5 % of the nominal capacity since

2010, this procedure would appear to be justified if the

currently high level of security of supply of 99.998 % [11]

is to be maintained (see Figure 1).

Worthy of mention is the ten-day cold dark doldrums

from 16 to 25 January 2017, during which the weather in

Germany was simultaneously cold, foggy and windless.

The weather conditions led to all wind turbines and photovoltaic

systems in Germany feeding a mere average of just

under 4,600 MW into the grid over these ten days, with an

iRES nominal capacity of around 90,000 MW. Wind power

accounted for three quarters of this iRES average power

output.

On several days the German wind fleet at times supplied

less than 1,800 MW or 2 % of its nominal capacity over

several consecutive hours, while biomass, hydropower and

geothermal energy together contributed a largely constant

power output of 6,300 MW.

During the ten-day dark doldrums, all renewable

energy systems (RES) together covered 15 % of the demand

and produced an average power output of around

11,000 MW.

The RES minimum output of around 7,000 MW

occurred on 23 January 2017 between 00:00 and 00:45.

This corresponded to about 6 % of the RES nominal

capacity [5].

During the cold dark doldrums the load varied between

42,000 MW and 75,000 MW (average: 61,000 MW), so

that available conventional power plants had to contribute

most to meeting demand with power outputs of 33,000 to

67,000 MW [14].

Note: The load has been provided via internet from the

transparency platform of ENTSO-E, the European Network

of Transmission System Operators [1]. It includes grid

losses and can be calculated from gross power generation

Probability in % (CDF)

100

90

80

70

60

50

40

30

20

10

CDF: Cumulative distribution function

Electricity generation from wind power

η A,Min

η A,Max

Normalised power P/PN in %

PMax /PN

| | Fig. 2.

Cumulative probabilities of hourly power output P of the German wind fleet

from 2010 to 2017 normalised to the nominal capacity P N at year-end.

by deducting the auxiliary consumption of power plants,

the balance of imports and exports and the demand of

pumped storage power plants. However, contributions

from German railways’ captive generation, industry-owned

power plants, small combined heat and power units and

small-scale plants based on renewables are not recorded by

German transmission system operators. These account for

around 10 % of the load and are not included in load data

obainable from ENTSO-E. Since the temporal pattern of

these contributions is unknown, load remains unchanged

and is used here to represent the domestic load curve.

These data derived from the January 2017 cold dark

doldrums characterise requirements that have to be

imposed on a backup system which will have to replace the

conventional power plants in future with further iRES

expansion, if the grid is to be operated stably and with

security of supply.

The fact that sustained periods of weak wind occur not

only in Germany but also in other European countries is

demonstrated by the public debate on electricity generation

from wind power in Great Britain, which was down

40 % year-on-year in July 2018. For weeks, the wind fleet

power output ranged from a few hundred to about

3,000 MW, reaching a monthly average of 9 % of the

nominal capacity. When good wind conditions prevail, the

power output in Great Britain typically reaches 9,000 to

10,000 MW [15].

Figure 2 shows cumulative probabilities of the normalised

hourly power output P of the German wind fleet for

the years 2010 to 2017 in relation to the nominal capacity

P N at year-end. CDF denotes the cumulative distribution

function. The ratio of the mean power output P µ to the

nominal capacity P N is defined as capacity factor h A .

It is immediately apparent that the cumulative distribution

functions are not in chronological order corresponding

to the expanded German wind fleet in terms of

nominal capacity. The minimum capacity factor h A,Min of

about 15 % was reached in 2014 at a nominal capacity of

almost 39,000 MW, for instance, and not earlier in 2010

when the development level was lower at around

27,000 MW. Therefore, wind conditions varying from year

to year seem to be one of the main drivers for the capacity

factor of the German wind fleet.

The highest capacity factor h A,Max of 21 % was recorded

in the extremely windy year 2017 when the wind fleet was

at its most developed. In terms of wind strength the years

2015, 2016, 2011, 2012, 2013, 2010 and 2014 follow in

descending order.

Hourly resolution

2017

2016

2015

2014

2013

2012

2011

2010

0

0 10 20 30 40 50 60 70 80 90 100

Sources: ENTSO-E, German TSO

SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 81

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SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 82

Nomoinal power in MW

60,000

50,000

40,000

30,000

20,000

10,000

0

Wind turbines

The Federal Ministry for Economic Affairs and Energy

(BMWi) [5] and the Working Group on Energy Balances

(AGEB) [6] partly report higher values for annual electricity

generation from wind power from 2010 to 2014 than result

from integrating quarter-hourly power time series published

by the German transmission system operators on

their transparency platforms via internet. This can result in

differing capacity factor values for individual years

depending on the relevant data source. As of the year 2015,

these deviations are all less than 5 % of the annual electric

energy supplied.

Note: Where not stated otherwise, this study is based

on the annual electric energy computed from power time

series and nominal capacities at year-end.

With dynamic expansion during the course of the year,

use of the annual mean value of the nominal capacity is

more appropriate. For the German offshore wind fleet

which was expanded strongly in 2017, a capacity factor of

37 % results with the year-end figure for nominal capacity

of 5,400 MW, while the annual mean value of 4,800 MW

leads to a considerably higher capacity factor of 42 %. The

latter takes more appropriate account of the fact that wind

turbines added during the course of the year were only

able to feed-in power on a pro rata temporis basis.

Total nominal power 2017 of 18 countries

≈170,000 MW

DE ES UK FR IT SE PL DK PT NL RO IE AT BE GR FI NO CZ

Europe 2017

| | Fig. 3.

Nominal capacity of wind turbines in 18 European countries at the end of 2017.

PT

IE

ES

UK

FR

NL

BE

NO

DE

DK

SE

IT

AT

CZ

Source: BP Statistical Review

| | Fig. 4.

Overview of 18 European countries analysed. Germany’s direct neighbours are written in red,

all countries further afield in blue.

FI

PL

RO

GR

18 European Countries

AT Austria

BE Belgium

CZ Czech Republic

DE Germany

DK Denmark

ES Spain

FI Finland

FR France

GR Greece

IE Ireland

IT Italy

NL Netherlands

NO Norway

PL Poland

PT Portugal

RO Romania

SE Sweden

UK United Kingdom

Looking at the German wind fleet as a whole, the mean

output of 11,700 MW and the year-end nominal capacity of

56,000 MW result in a capacity factor of 21 % for 2017. The

annual mean value of the nominal capacity of 53,000 MW

results in a marginally higher capacity factor of 22 % on

account of the low leverage of newly added nominal

capacity compared with the existing level. When comparing

with the capacity factor of electricity generation from wind

power in other European countries, relative differences are

of interest, and so calculations for such considerations

should be carried out in a uniform manner for all countries.

Although the capacity factor of the German offshore wind

fleet last year was practically almost double that of the entire

German wind fleet, the quarter-hourly power output of the

German offshore wind fleet fell to 1 % of its nominal capacity

or less in a total of around 261 hours of the 8,760 annual

hours. In 2016 this was 259 hours (2015: 304 hours). Weak

wind phases of this kind occurred in each month of last year,

including pronounced phases lasting several hours in January,

March, April, June, July, August and September. The

power output of the German offshore wind fleet fell at times

in January, April, July, August and September to 0 MW. Over

the entire year, 29 quarter- hourly zero values were recorded.

This means that at the level of development achieved to

date, the German offshore wind fleet is shown to be not

capable of serving as a source of baseload electricity and

cannot replace conventional power plants.

Whilst the nominal capacity of the German wind fleet

has more than doubled since 2010, wind levels depend on

meteorological influencing variables and can vary considerably

from year to year. This is documented by longterm

data on the capacity factor of the German wind fleet

with annual fluctuations in a range of up to ±20 % in

relation to the long-term arithmetical mean [5].

The influence of meteorological factors is apparent, for

example, in Figure 2 in the fact that the German wind fleet

produced up to 50 % of the nominal capacity in 93 % of the

annual hours in 2015 and 2017, when wind levels were

high, but in 2010 and 2014, when wind levels were low,

only achieved at most 38 % and 41 % respectively of

the nominal capacity in 93 % of the annual hours. This

corresponds to a weather-induced variance of around

twelve percentage points.

With low cumulative probabilities and at low normalised

output, differences of this kind between indivi dual

years on account of meteorological influences are barely

discernible. Cumulative probabilities of 100 % were

reached in Germany in the past years at wind fleet power

outputs of 68 to 80 % of the nominal capacity. Or in other

words: The German wind fleet recorded annual power

output maxima of 68 to 80 % of its nominal capacity in the

last eight years. In Germany, therefore, it is never the case

that all wind turbines feed their nominal capacity into the

grid at the same time. But is that also true of other European

countries? Can a similar relationship between the annual

maximum power output P max and the nominal capacity P N

be derived from their power output time series?

On the basis of 108 time series for electricity generation

from onshore and offshore wind power in European countries

between 2010 and 2017 [14], regression analysis

provides the following interrelation to be derived between

the annual maximum power output P max and the nominal

capacity P N at year-end, with a degree of determination of

linear regression of 99 %:

P Max = c Max · P N .

The slope of this linear equation can be expressed as:

c Max = 0.726 ± 0.014.

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atw Vol. 64 (2019) | Issue 2 ı February

Long-term operating experience in various European

countries including Germany thus enables with good

approximation the expectation that, at best, just under

74 % of the nominal capacity of a wind fleet of any one

European country contribute simultaneously to the

maximum power output. As electricity generation from

wind power expands, the difference between the nominal

capacity and the annual maximum power output consequently

increases, see Figure 1.

The data basis cited above also enables an approximate

linear dependency on the nominal capacity P N to be

derived for the mean value P µ with a 96 % degree of

determination:

P µ = c µ · P N .

The slope of this linear equation is expressed as:

c µ = 0.179 ± 0.009.

Long-term operating experience documents here that,

at best, approximately just under one fifth of the nominal

capacity of a wind fleet in any one European country

contributes to the annual electric energy supplied.

Last but not least, the data basis cited above also enables

an approximate linear dependency on the nominal capa city

P N to be derived for the standard deviation P s as a measure

of the dispersion of the power output around the mean

value P µ with a degree of determination of almost 99 %:

P s = c s · P N .

The slope of this linear equation can be expressed as:

c s = 0.145 ± 0.0036.

Based on long-term operating experience, a proportional

increase in power output fluctuations relative to the

nominal capacity can be derived in this case with a factor

of almost 0.15. With further expansion of wind power,

therefore, a further increase in power output fluctuations

is to be expected.

It can therefore be concluded that operating experience

of 2017 confirms the statements made in the first part of

the VGB Wind Study for Germany [1], namely that, from

the point of view of security of supply, wind power has so

far not replaced conventional power plant output. Furthermore,

distribution of wind turbines throughout Germany

is, on its own, clearly not a solution for a reliable and secure

supply of electricity. Complementary technologies are

necessary in conjunction with wind power. This raises the

question as to whether wind turbines distributed widely

throughout Europe could help.

Power in MW

Power in MW

Power in MW

100,000

90,000

80,000

70,000

60,000

50,000

40,000

30,000

20,000

10,000

0

100,000

90,000

80,000

70,000

60,000

50,000

40,000

30,000

20,000

10,000

0

100,000

90,000

80,000

70,000

60,000

50,000

40,000

30,000

20,000

10,000

0

Jan

Jan

Jan

Germany

P N ≈ 56,000 MW

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Germany plus seven countries

P N ≈ 93,000 MW

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Germany plus seventeen countries

P N ≈ 170,000 MW

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Year 2017

Hourly resolution

| | Fig. 5.

Cumulative power time series for electricity generation from wind power in 2017

for Germany (top), for Germany plus seven direct neighbours (centre) and for

Germany plus seventeen countries (bottom).

Dec

Dec

Dec

Source: ENTSO-E

SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 83

Electricity generation from wind power

in 18 European countries

In order to answer this question, it is first worth taking a

look at the cumulative nominal capacity of wind turbines

operated in 18 European countries at the end of 2017 or

the total nominal capacity of the European wind fleet of

almost 170,000 MW, 91 % of which was accounted for by

onshore wind turbines and 9 % by offshore wind turbines

(Figure 3) [16]. In 2017, offshore wind turbines were

operated in Belgium (BE), Denmark (DK), Germany (DE),

the Netherlands (NL) and the United Kingdom (UK).

Countries with largely intact time series on electricity

generation from wind power were selected, reflecting 94 % of

the European nominal capacity at the end of 2017 [14],[16].

Starting point of these analyses were transparency data

accessible on the internet from ENTSO-E [14], the German

transmission system operators 50 Hertz Transmission,

Amprion, Tennet TSO and Transnet BW as well as the

European Energy Exchange [17] to [21].

Time series for electric power output from various power

plant types, including wind turbines and photo voltaic

systems, as well as for consumer demand (load) can be

retrieved through these transparency platforms in quarterhourly

to hourly resolution.

On the ENTSO-E transparency platform, all time series

from 2015 on were retrievable in time-synchronised form,

an important factor for analyses of balance between

consumption and generation in different countries.

This enabled consistent retrieval of data according to coordinated

universal time. Additional information on data

qualification and plausibility can be found in the first part

of the VGB Wind Study [1].

Figure 3 shows: Germany alone, with around

56,000 MW, accounted for almost one third of the total

nominal capacity of the European wind fleet, followed at a

clear distance by Spain (14 %), the United Kingdom

(12 %), France (8 %) and Italy (6 %).

Figure 4 shows a map of the 18 European countries

considered here. Germany’s direct neighbours are written

in red, all countries further afield in blue. Germany’s seven

direct neighbours (AT, BE, CZ, DK, FR, NL, PL) currently

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SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 84

Country P N P Max P µ P Min P s E R E R [16]

in MW in MW in MW in MW in MW in TWh in TWh

DE 56,164 39,231 11,720 165 8,813 102.7 106.6

DK 5,476 4,685 1,644 9 1,154 14.4 14.8

PL 6,397 5,234 1,633 28 1,238 14.3 14.9

CZ 308 237 64 1 51 0.6 0.6

AT 2,828 2,679 768 0 676 6.7 6.5

FR 13,759 10,290 2,608 390 1,887 22.8 24.3

BE 2,843 2,082 572 3 471 5.0 6.6

NL 5,070 4,280 1,255 7 1,010 11.0 10.6

DE+7 92,845 61,773 20,265 1,742 12,840 177.5 184.9

SE 6,691 5,523 1,976 117 1,092 17.3 17.3

FI 2,113 1,607 470 9 361 4.1 4.8

RO 3,029 2,756 834 0 692 7.3 7.4

GR 2,651 1,702 483 16 336 4.2 5.5

IT 9,479 6,696 2,005 40 1,462 17.6 17.7

ES 23,170 15,564 5,384 420 3,017 47.2 49.1

PT 5,316 4,471 1,367 5 988 12.0 12.3

IE 3,127 2,595 825 0 602 7.2 7.4

UK 18,872 11,394 4,726 431 2,507 41.4 49.6

NO 1,162 975 306 6 184 2.7 2.8

DE+17 168,455 91,638 38,639 7,855 16,384 338.5 358.8

| | Tab. 1.

Relevant parameters of electricity generation from wind power of 18 European countries in 2017 with

year-end value of nominal capacity P N , maximum value P Max , mean value P µ , minimum value P Min and

standard deviation P s of hourly power output of the corresponding national wind fleet. Furthermore,

the annual energy ER resulting from 8,760 hourly values is shown and compared with the annual

energy published in the BP Statistical Review of World Energy [16].

account for around one fifth of the nominal capacity of the

European wind fleet, while the other ten countries further

afield (ES, FI, GR, IE, IT, NO, PT, RO, SE, UK) make up

about half of this total nominal capacity.

The yellow dots on the map of Europe symbolise the

wind fleet centers of the individual countries, determined

on the basis of geocoordinates of the largest wind farm

clusters in 2016 [22]. The focus of the German wind fleet

and that of the European wind fleet formed by the

18 countries, at almost 140 km distance apart, are almost

congruent.

The largest distance between wind fleet centers is to be

found with the country pair Finland and Portugal at almost

3,300 km, followed by Spain and Finland (≈ 3,100 km),

Greece and Ireland (≈ 3,000 km), Portugal and Romania,

and Greece and Norway (both ≈ 2,900 km).

On the assumption that all countries are to help each

other out by means of wind power, a mean transport

distance of 1,500 km between two wind fleet centers

results from a total of 153 possible country pairs when

18 countries are considered.

The summation of power outputs of wind fleets of

18 European countries observed here is based on the

extremely simplistic assumption of a copper plate across

Europe, neglecting any losses in the transport and distribution

networks. Or in other words: the aggregate power output

is accessible at a punctiform feed-in point, so to speak.

Figure 5 shows the cumulative time series of the hourly

generation of electricity from wind power for Germany

(top), for Germany plus seven direct neighbours (centre)

and for Germany plus 17 European countries (bottom) in

2017. Table 1 lists supplementary operating parameters

and energy variables.

Firstly, it is apparent that not only do the cumulative

power time series of the wind fleet in Germany (DE) reveal

considerable temporal fluctuations, so too do those of

cumulative wind fleets of Germany plus seven countries

(DE+7) or 17 countries (DE+17).

It is apparent that aggregate power outputs of several

countries are also still correlated, as demonstrated by the

distinct power output maxima and minima, which

evidently often occur simultaneously in many countries.

This raises the question as to whether smoothing effects

can be identified in the transition from one individual

country to several countries.

In a first step, the question can be evaluated on the basis

of the range between the largest and smallest power output

values in relation to the nominal capacity P N .

This range, referred to here as variation range, is

defined as the ratio of the difference of the mean values of

the largest power output values (P Max minus 5 % P N ) and

the smallest power output values (P Min plus 5 % P N ) to the

nominal capacity of the relevant wind fleet.

Applied to the three wind fleets the following picture

emerges: the variation range of the cumulative power time

series falls by one tenth to around 61 % of the nominal

capacity starting from Germany when Germany plus seven

countries are considered together, whereas it decreases by

one third to 46 % for Germany plus 17 countries (DE+17).

A certain degree of smoothing in subsections of the cumulative

power time series therefore appears to take place.

But what statements can be made − in statistical terms

− for the entire cumulative power time series? The variation

coefficient x as ratio of the standard deviation P s to

the mean value P µ is a dimensionless measure of the dispersion

of a time series.

For an individual European country, the variation

coefficient can be estimated as approximately x = c s /c µ

≈ 0.81 with the results of the previously described linear

regression analysis. For an individual European country,

even just small deviations from the mean value by 1.2

standard deviations downwards lead to power outputs

of 0 MW, as already stated with the example of Germany

in [1].

The cumulative power time series of eight European

countries (DE+7), on the other hand, results in a variation

coefficient of x DE+7 ≈ 0.63. Consequently, in this case, only

deviations by 1.6 standard deviations from the mean value

downwards lead to power outputs of 0 MW.

For the cumulative power time series of 18 European

countries (DE+17), an even lower variation coefficient of

x DE+17 ≈ 0.42 results. In this case, only even deviations by

2.4 standard deviations from the mean value downwards

lead to power outputs of 0 MW.

These considerations suggest a degree of balancing

in the generation of electricity from wind power or

smoothing effects when the power time series of European

countries are superimposed. Figure 6 illustrates this

smoothing effect on the basis of the cumulative probabilities

of the normalised hourly power output P of the

European wind fleet for the year 2017 relative to the

nominal capacity P N at the end of the year compared with

the range of cumulative probabilities for Germany from

2010 to 2017.

The European wind fleet reached an annual power

output maximum of 54 % of the nominal capacity and a

capacity factor of 23 %. By comparison, the cumulative

power time series of the hourly power output of individual

years for Germany (see Figure 2) show annual maximum

power output values of around 68 to 80 % of the nominal

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atw Vol. 64 (2019) | Issue 2 ı February

capacity. For an average individual European country, the

linear regression analysis described above would give in

good approximation annual maximum values of around

73 % of the nominal capacity.

The difference between nominal capacity and annual

maximum power output therefore increases more significantly

when several countries are considered cumulatively

than it does for a single country.

A glance at annual minimum power outputs confirms

that even when considered conservatively neglecting any

grid losses, relatively low permanently available (secured

capacity) power outputs result. In 2017 the result for

the European wind fleet was around 5 % of the nominal

capacity or just under 7,900 MW. By comparison, the

annual minimum value for Germany amounted to 0.3 % of

the nominal capacity or 165 MW, and for Germany plus its

seven direct neighbours to 2 % or almost 1,800 MW.

However, these annual minimum values cannot be

comprehended with simple linear upscaling. At the end of

2017, for example, around one third of the nominal

capacity of the European wind fleet was accounted for by

the German wind fleet. Tripling the German annual

minimum value in order to make a projection would lead

to an expectation of an annual minimum value of 495 MW

for the European wind fleet. In actual fact, this annual

minimum value is almost 48 times higher. A certain degree

of balancing thus demonstrably occurs.

Buttler et al. [23] evaluated time series on electricity

generation from wind power in 2014 in 28 countries of the

European Union based on the copper plate model and in

connection with the cumulative power time series of this

European wind fleet speak of a statistically significant

smoothing effect which leads to a (secured) power output

capable of serving as a source of baseload electricity available

all year round of 4 % of the nominal capacity. The

secured power output of this European wind fleet during

the year increases with restriction to winter months, at

times therefore, to around 9 % of the nominal capacity.

As the cumulative time series of the load of the

European countries in these months is likewise characterised

by distinctly increasing demand, as shown by the

trend line for the hourly load curve of these countries in

Figure 7 (assumption: no grid losses), the evaluation result

does not improve decisively even with consideration of

the electricity generation from wind power during the

course of the year.

The annual mean value of the cumulative time series of

the hourly load in the 18 countries amounted to around

327,000 MW in 2017. If restricted to the four winter months

from November to February, a four-month mean value of

around 366,000 MW results. Were the secured capacity of

the European wind fleet to be doubled on account of the

winter to 10 % of its nominal capacity, the four-month

mean value of the load, which is 39,000 MW higher than

its annual mean value, would face an increase of the secured

capacity of the European wind fleet at times of

around 9,000 MW.

In 2017 the European wind fleet supplied a total of

around 340 TWh of electricity. The total demand for electricity

calculated from the cumulative time series of the

hourly load of the 18 European countries amounted to

around 2,900 TWh.

Wind power contributed approximately 12 % towards

covering the demand for electricity. By comparison, the international

energy statistics for gross power generation of

these 18 European countries in 2017 reveal a level of just

under 3,300 TWh [16].

Probability in % (CDF)

Bandwidth

CDF: Cumulative distribution function

Power in MW

100

90

80

70

60

50

40

30

20

10

Normalised power P/PN in %

| | Fig. 6.

Cumulative probabilities of the hourly power output P of the European wind fleet

normalised to the nominal capacity P N at year-end and the corresponding range of

cumulative probabilities for Germany from 2010 to 2017.

| | Fig. 7.

Electricity generation from wind power and load in 18 European countries in 2017.

On the one hand, the difference of around 400 TWh

between the gross power generation and the demand

calculated from the load results from the power plant

auxiliary electric load, the balance of imports and exports

and the power consumption of pumped storage power

plants in all 18 countries which are not considered in the

hourly load in accordance with the ENTSO-E definition. On

the other hand, not all consumers are depicted to 100 %, for

example the consumption by German industry covered by

its own power plants, which is not recorded publicly.

Figure 7 also illustrates the high temporal correlation

of the hourly load curves in the 18 European countries

with distinct weekly and daily cycles. In the event of loads

being balanced across all countries, these cycles should not

be so pronounced.

Figure 8 shows that the power output of the European

onshore wind fleet (dark blue) is frequently concurrent with

the power output of the European offshore wind fleet

( orange) and that significant temporal output fluctuations

occur. While the European onshore wind fleet had a nominal

capacity of almost 153,000 MW at the end of 2017, offshore

wind turbines with a nominal capacity of 15,500 MW were

in use in five countries: Belgium, Denmark, Germany, the

Netherlands and the United Kingdom.

Unlike in Germany, the annual minimum power output

of the offshore wind fleet in Europe at no time fell to 0 MW

on account of the more widespread distribution of wind

turbines in the North and Baltic Seas, instead amounting

to 89 MW (hourly resolution).

Hourly resolution

0

0 10 20 30 40 50 60 70 80 90 100

500,000

450,000

400,000

350,000

300,000

250,000

200,000

150,000

100,000

50,000

0

Electricity generation from wind power

Nominal power

Jan

η A = Pµ /PN

Year 2017

PMax /PN

Europe 2017

Germany 2010 to 2017

Load curve

Mean

Trend line

Electricity generation from wind power

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Sources: ENTSO-E, ÜNB

Hourly resolution

Dec

Source: ENTSO-E

SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 85

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Wind Energy in Germany and Europe ı Thomas Linnemann and Guido S. Vallana


atw Vol. 64 (2019) | Issue 2 ı February

SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 86

Power in MW

Spearman rank correlation coefficient rS

100,000

Normalised power P/P N in %

90,000

80,000

70,000

60,000

50,000

40,000

30,000

20,000

10,000

0

100

90

80

70

60

50

40

30

20

10

0

This corresponds to just under 0.6 % of the relevant

nominal capacity. Minor contributions of 1 % of the

nominal capacity or less were observed in ten of the 8,760

annual hours, aggregate power outputs of 5 % of the

nominal capacity or less in 319 hours and aggregate power

outputs of less than 10 % in 1,100 hours or in total on

45 days. This means that the European offshore wind fleet,

too, at its current level of development, in practice cannot

serve as a source of baseload electricity.

The normalised aggregate power outputs of the onshore

and offshore wind fleets illustrate that the expansion of

both wind fleets that has taken place so far across Europe is

evidently insufficient for balancing to a degree that would

Jan

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Year 2017

Source: ENTSO-E

| | Fig. 8.

Cumulative time series of the hourly power output of onshore (blue) and offshore

( orange) wind power in 18 European countries in 2017 and normalised cumulative time

series assuming linear growth of the nominal capacity of onshore (blue) and offshore

( orange, in the background) wind power over the course of the year.

0.9

0.8

0.7

0.6

0.5

0.4

0.3

0.2

0.1

0.0

-0.1

Jan

Onshore wind power: P N ≈ 153,000 MW

Offshore wind power: P N ≈ 15,500 MW

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Electricity generation from windpower 2016

BE

NL

PL

NL

DK

CZ

BE

DE

AT

Germany‘s direct neighbours

DE

FR

Negatively correlated country pairs

Onshore wind power

Offshore wind power (underlayed)

Mean distance ∆x in km

Hourly resolution

| | Fig. 9.

Spearman rank correlation coefficient r S as a function of the mean distance ∆x between

national wind fleet centers for 18 countries, calculated on the basis of hourly power time series

in 2016. Besides Belgium and the Netherlands as the country pair with the highest correlation

coefficient, also highlighted in colour are seven of Germany’s direct neighbours, Finland and

Portugal as country pair with the furthest mean distance, as well as Spain and Finland and

Spain and Sweden as the two country pairs with the lowest correlation coefficients.

Dec

Dec

Hourly resolution

Coefficient of determination of trend line: R 2 = 0,7897

-0.2

0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000

ES

SE

ES

FI

FI

PT

Source: ENTSO-E

enable backup power plant capacity to be dispensed with

to a perceptible extent: the superimposed aggregate power

outputs of both wind fleets indicate which gaps in power

output can be closed and which peaks will increase further.

The result is disenchanting: gaps are only closed to a

limited extent, peaks continue to increase. The correlation

of the power feed-ins is clearly visible.

This raises the question as to whether better results

could be obtained, as suggested by Grams et al. [24] and

Becker [25], by increased integration of European

countries located far apart from each other. A spatial

correlation analysis and close scrutiny of grid losses are

suitable means of evaluating this idea.

Spatial correlation analysis

Spatial correlation analyses explore from a mathe matical

point of view how data depend on each other. In this case,

the question is whether and to what extent the cumulative

time series for the hourly power output of two national

wind fleets depend on their mean distance from each

other, i.e. correlate spatially.

The correlation coefficient r K is generally a measure of

the direction and strength of a correlation and can assume

values in the range from -1 to +1. It is necessary to

distinguish here between the following cases:

pp

With perfectly correlated data, the correlation coefficient

assumes values of +1 (positive) or -1 ( negative). The

changes are exactly equally strong. The direction of

change, however, is either exactly the same (+1) or

exactly opposite (-1). An example of a perfectly positive

corre lation would be the speeds of two vehicles linked by

a tow bar.

pp

In the case of uncorrelated data, the correlation

coefficient is r K = 0. This result could be expected, for

example, when comparing house numbers with the

shoe sizes of the inhabitants.

pp

With positive correlation, the correlation coefficient

assumes positive values of more than 0 and less than 1.

Positive correlation coefficients could be expected

when comparing body height and shoe size. This would

be a parallel development. As body height increases, so

too, as a general rule, does the shoe size.

pp

With negative correlation, the correlation coefficient

lies in the range from more than -1 to less than 0.

An example for negatively correlated data are the outside

temperature and the number of skiers in a winter

holiday region. This is an opposite development. The

number of skiers generally increases as the outside

temperature decreases.

The spatial correlation analysis to be carried out here was

based on the 18 time series on hourly electricity generation

from wind power for 2016 and the centers of 18 national

wind fleets. The total number n of possible combinations

of country combinations (pairs) can be calculated from the

number z of countries according to the following equation:

n = ½·z·(z−1).

In case of 18 countries a total of 153 possible country

pairs and 153 mean distances ∆x between national wind

fleets have to be considered.

As the power time series for these 18 countries are shown

to be not normally distributed, Spearman’s rank correlation

procedure was selected. This procedure is resistant to outliers

and uses the hourly resolution, converted into ranks, of

time series of electricity generation from wind power of in

each case two national wind fleets to calculate the Spearman

rank correlation coefficient r S for 153 country pairs, hereinafter

referred to in simplified form as correlation coefficient.

Serial | Major Trends in Energy Policy and Nuclear Power

Wind Energy in Germany and Europe ı Thomas Linnemann and Guido S. Vallana


atw Vol. 64 (2019) | Issue 2 ı February

Normalised power P/P N in %

Normalised power P/P N in %

Normalised power P/P N in %

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

Jan

Jan

Jan

Netherlands

Belgium

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

France

Germany

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Austria

Germany

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Year 2016

∆x ≈ 200 km

r S ≈ 0.8

∆x ≈ 900 km

r S ≈ 0.4

∆x ≈ 600 km

r S ≈ 0.2

| | Fig. 10.

Normalised hourly power output time series of wind fleets of neighbouring countries

with positive Spearman rank correlation coefficients in 2016.

To determine the mean distances between the national

wind fleets, the wind fleet centers of the 18 countries first

had to be established. Weighted position coordinates of

about the five to fifteen largest wind farm clusters of the

relevant country in 2016 formed the basis for this [22].

153 mean distances for the individual national wind fleets

in relation to each other subsequently had to be established.

Using Google Maps, the distances between the centers of

all national wind fleets in relation to each other could be

determined, the result of which is shown in Figure 9.

Belgium and the Netherlands, with a mean distance of

around 200 km between their wind fleet centers, reach the

maximum correlation coefficient of 0.8.

Six of Germany’s direct neighbours, namely the Netherlands,

Denmark, the Czech Republic, Poland, Belgium and

France, record correlation coefficients of 0.4 or more with

mean distances of just under 400 to 900 km. Austria

constitutes an exception, with a correlation coefficient of a

mere 0.2 at a mean distance of just under 600 km. Possible

reasons for the higher level of detachment compared with

Germany’s other direct neighbours could be the mountain

ranges of the Alps and the altitude of the Austrian wind fleet.

Hourly values

Dec

Dec

Dec

Source: ENTSO-E

Normalised power P/P N in %

Normalised power P/P N in %

Normalised power P/P N in %

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

100

90

80

70

60

50

40

30

20

10

0

Jan

Jan

Jan

Portugal

Finland

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Finland

Spain

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Sweden

Spain

Feb Mrz Apr May Jun Jul Aug Sep Oct Nov

Year 2016

∆x ≈ 3,300 km

r S ≈ −0.003

∆x ≈ 3,100 km

r S ≈ −0.077

∆x ≈ 2,400 km

r S ≈ −0.118

| | Fig. 11.

Normalised hourly power output time series of wind fleets of countries long

distances apart with negative Spearman rank correlation coefficients in 2016.

With all correlation coefficients over 0.4, the power outputs

of the national wind fleets of individual neighbouring

countries develop in a largely synchronised manner, and so

smoothing effects are barely identifiable, or are limited at

most, as illustrated in Figure 10 with examples of hourly

power output in 2016 normalised to the nominal capacity

of wind fleets of Belgium and the Netherlands, Germany

and France, and Germany and Austria.

The normalised aggregate power outputs of these

countries, overlaid like two combs, give an idea of the gaps

in output that could be closed if the wind fleets of these

country pairs were to be coupled, and which peaks would

increase further. The result is that gaps in output are barely

filled, and the peaks increase further. The correlation of

power outputs is clearly visible.

It can therefore be concluded that neighbouring

countries showing consistently positive correlation

coefficients of 0.2 to 0.8, with centers of their national

wind fleets at a distance of 200 to 900 km apart, can

barely make any perceptible contribution to the aspired

cross- border balancing of electricity generation from

wind power.

Hourly resolution

Dec

Dec

Dec

Source: ENTSO-E

SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 87

Serial | Major Trends in Energy Policy and Nuclear Power

Wind Energy in Germany and Europe ı Thomas Linnemann and Guido S. Vallana


atw Vol. 64 (2019) | Issue 2 ı February

SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 88

Analyses on the basis of wind speed measurement data

at 27 locations in the Netherlands confirm correlation

lengths of several hundred kilometres such as these [26].

In France, the annual minimum output of around 2.7 % of

the nominal capacity is strikingly high compared with all of

Germany’s other neighbours. One reason for this could be the

vast French coastline running in westerly ( Atlantic) and

north- westerly (English Channel) direction. Spain and the

United Kingdom likewise display annual minimum values

which are consistently well above 1 % of the nominal capacity.

One would intuitively expect that balancing of electricity

generation from wind power would most likely be

found in those country pairs which are furthest away from

each other or which have the lowest possible correlation

coefficients. However, negative correlation coefficients

only occur at all with 12 of the 153 country pairs.

The national wind fleets of Finland and Portugal are the

furthest apart from each other, at a distance of 3,300 km.

This results in a negative correlation coefficient of -0.003

for these countries. Uncorrelated to slightly opposing

power time series can be expected here. The wind fleet

centers of Spain and Finland are second furthest from each

other, at 3,100 km. These countries also display a negative

correlation coefficient of -0.077. Spain and Sweden have

the lowest correlation coefficient, at -0.118. Their wind

fleet centers are around 2,400 km apart.

Normalised hourly power output time series are again

overlaid like two combs for these distant country pairs in

Figure 11. Although the fraction of blue areas of the corresponding

electricity generation from wind power shown

in the background increases compared with posi tively correlated

time series according to Figure 10, it is apparent

that numerous gaps in output barely balance and many

peaks still correlate with each other, even with uncorrelated

(r S ≈ 0) to slightly negatively correlated (r S < 0) hourly

resolutions of electricity generation from wind power.

Thus a majority of temporal fluctuations in the generation

of electricity from wind power remain, even with

countries far apart from each other. Moreover, the use of

the smoothing effects apparent to some extent requires

electricity to be transmitted over long distances.

Summary

VGB PowerTech has carried out a plausibility check of

electricity generation from wind power in Germany and 17

neighbouring European countries and in the process explored

questions as to whether adequate possibilities for mutual

balancing exist within the interconnected European grid true

to the motto “the wind is always blowing somewhere”.

In the current energy policy environment which,

against the backdrop of the international climate protection

commitments facing Germany, seeks to abandon the

power plant technology proven over decades and create

extensive provision of electricity from renewable energies,

photovoltaics and wind power remain the only scalable

technologies capable of further development for the

Energie wende in the short to medium term. However, they

are always reliant on complementary technologies.

Looking back at the past year in Germany, it can be

concluded that additional operating experience confirms

the statements made in the first part of the VGB Wind

Study: from the perspective of security of supply, wind

power, despite concerted efforts to expand since 2010, has

for all practical purposes not replaced any conventional

power plant capacity. Furthermore, offshore wind power

at its current level of development is shown to be not

capable of serving as a reliable source of baseload power

and cannot replace conventional power plant capacity.

Wind turbine locations spread throughout Germany are

not a solution for a reliable and secure supply of electricity.

Dispatchable complementary technologies are always

necessary in conjunction with wind power.

From a European perspective, it can be concluded on

the basis of 18 countries observed here that although

statistically significant smoothing effects are to be seen,

these only help to a limited extent when it comes to security

of supply: 4 to 5 % of the nominal capacity means with

consideration of unavoidable grid losses that, even at a European

level, dispatchable backup capacity of almost 100

% of the nominal capacity of all European wind turbines

has to be maintained, as long as this has not yet exceeded

the annual peak load in Europe plus reserves.

Acknowledgements

The authors thank Professor Dr. Dr. h.c. mult. Friedrich

Wagner from Max Planck Institute for Plasma Physics in

Greifswald for his valuable suggestions and contributions

to this publication.

Literature

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challenges for baseload application, Part 1: Developments in Germany since 2010. VGB PowerTech 97

(2017), No. 8, pp. 70 bis 79.

[2] Linnemann, Th.; Vallana, G. S.: Wind energy in Germany and Europe: Status, potentials and

challenges for baseload application, Part 1: Developments in Germany since 2010. atw 62 (2017),

No. 11, pp. 678 to 688.

[3] Weber, H.: Versorgungssicherheit und Systemstabilität beim Übergang zur regenerativen

elektrischen Energieversorgung. VGB PowerTech 94 (2014), No. 8, pp. 26-31.

[4] Bericht der deutschen Übertragungsnetzbetreiber zur Leistungsbilanz 2016 bis 2020.

Version 1.1 dated 30 January 2018. www.netztransparenz.de

[5] BMWi-Zeitreihen zur Entwicklung der erneuerbaren Energien in Deutschland von 1990 bis 2016.

www.erneuerbare-energien.de

[6] Arbeitsgemeinschaft Energiebilanzen (AGEB): Bruttostromerzeugung in Deutschland ab 1990

nach Energieträgern. www.ag-energiebilanzen.de

[7] BDEW: Stromerzeugung und -verbrauch 2017 in Deutschland. BDEW-Schnellstatistik dated

14 February 2018. www.bdew.de

[8] Bundesnetzagentur: Monitoringbericht 2017. www.bundesnetzagentur.de

[9] Wagner, F.: Surplus from and storage of electricity generated by intermittent sources. European

Physical Journal Plus 131 (2016): 445. https://epjplus.epj.org DOI 10.1140/epjp/i2016-16445-3

[10] Wagner, F.: Überschussstrom und Stromspeicherung unter den Bedingungen intermittierender

Produktion. Tagungsband zur Frühjahrssitzung des Arbeitskreises Energie der Deutschen

Physikalischen Gesellschaft (DPG), Münster, 2017, pp. 54 to 74.

www.dpg-physik.de/veroeffentlichung/ake-tagungsband/tagungsband-ake-2017.pdf

[11] VDE-Infoblatt Störungsstatistik 2016. www.vde.com

[12] Wagner, F.: Considerations for an EU-wide use of renewable energies for electricity generation.

Eur. Phys. J. Plus 129 (2014): 219. https://epjplus.epj.org DOI 10.1140/epjp/i2014-14219-7

[13] Rodriguez, R. A. et al.: Transmission needs across a fully renewable European power system.

Renewable Energy, 63 (2014), pp. 467 to 476. DOI 10.1016/j.renene.2013.10.005

[14] ENTSO-E Transparency Platform. https://transparency.entsoe.eu

[15] Vaughan, A.: UK summer wind drought puts green revolution into reverse. Article dated

27 August 2018. www.theguardian.com

[16] BP Statistical Review of World Energy 2018 − data workbook: www.bp.com

[17] 50 Hertz, www.50hertz.com

[18] Amprion, www.amprion.net

[19] Tennet TSO, www.tennet.eu

[20] Transnet BW, www.transnetbw.de

[21] EEX Transparency, www.eex-transparency.com

[22] Online database on the global wind power market: www.thewindpower.net

[23] Buttler, A.; Dinkel, F.; Franz, S.; Spliethoff, H.: Variability of wind and solar power. An assessment

of the current situation in the European Union based on the year 2014. Energy 106 (2016), pp. 147 to

161. DOI 10.1016/j.energy.2016.03.041

[24] Grams, C. M. et al.: Balancing Europe’s wind-power output through spatial development informed

by weather regimes. Nature Climate Change 7 (2017), pp. 557 to 562, DOI 10.1038/nclimate3338.

[25] Becker, P.: Wetterbedingte Risiken der Stromproduktion aus erneuerbaren Energien durch

kombinierten Einsatz von Windkraft und Photovoltaik reduzieren. Deutscher Wetterdienst (DWD),

6 March 2018, Berlin. www.dwd.de

[26] Baïle, R.; Muzy, J.-F.: Spatial Intermittency of Surface LayerWind Fluctuations at Mesoscale Range.

Physical Review Letters 105 (2010), pp. 254501-1 to 254501-4. DOI 10.1103/PhysRevLett.105.254501

Authors

Dipl.-Ing. Thomas Linnemann

Dipl.-Phys. Guido S. Vallana

VGB PowerTech e.V.

Deilbachtal 173

45257 Essen

Serial | Major Trends in Energy Policy and Nuclear Power

Wind Energy in Germany and Europe ı Thomas Linnemann and Guido S. Vallana


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atw Vol. 64 (2019) | Issue 2 ı February

Das neue Strahlenschutzrecht (I): Genehmigungen

90

SPOTLIGHT ON NUCLEAR LAW

Christian Raetzke

Wir haben ein neues Strahlenschutzrecht! Das Strahlenschutzgesetz (StrlSchG) ist, nachdem einzelne Elemente –

Definitionen, Verordnungsermächtigungen, die Regelungen zum Notfallschutz – schon zum 1. Oktober 2017 wirksam

wurden, am 31. Dezember 2018 nunmehr vollständig in Kraft getreten. Zum selben Datum ist auch die “Verordnung zur

weiteren Modernisierung des Strahlenschutzrechts” wirksam geworden, die die Änderungen auf der Verordnungsebene

– neue Strahlenschutzverordnung (StrlSchV), weitere Verordnungen, Aufhebung der Röntgenverordnung (RöV)

etc. – umsetzt. Bereits im Januarheft der atw konnten Sie, liebe Leserinnen und Leser, dazu die Einführung von Dr.

Goli-Schabnam Akbarian vom Bundesministerium für Umwelt, Naturschutz und nukleare Sicherheit (BMU) lesen. Mit

diesem Beitrag soll eine kleine Reihe beginnen, die in lockerer Folge erscheinen und Schlaglichter auf einzelne Aspekte

des neuen Rechts werfen wird.

Bei jeder grundlegenden Änderung von Gesetzen und

Verordnungen richtet sich der Blick des Anwenders

notwendig auf Übergangsvorschriften, die die Überleitung

auf das neue Recht gewährleisten sollen. Es handelt sich

hier um §§ 196 bis 218 StrlSchG und §§ 185 bis 200

StrlSchV n.F. (neuer Fassung).

Eine besonders wichtige Frage dabei: was geschieht

mit bestehenden Genehmigungen? Die bekannten

Genehmigungsvorschriften der alten StrlSchV und der

RöV sind in das StrlSchG übernommen und dort teils

zusammengeführt worden. Grundlegende inhaltliche

Änderungen haben sich dabei aber nicht ergeben. So ist es

nur konsequent, dass das Gesetz im Grundsatz die Fortgeltung

der bestehenden Genehmigungen anordnet. Man

muss als Genehmigungsinhaber also nicht etwa einen

neuen Antrag stellen.

Um ein Beispiel zu bringen: Genehmigungen für

den Umgang mit sonstigen radioaktiven Stoffen (§ 7

StrlSchV a.F.) gelten samt aller Nebenbestimmungen als

Genehmigungen nach der hierfür nunmehr einschlägigen

neuen Regelung in § 12 Abs. 1 Nr. 3 StrlSchG fort (siehe

§ 197 Abs. 2 S. 1 StrlSchG); hat sich am 31.12.2018 eine

Genehmigung nach §§ 6, 7 oder 9 AtG auf den Umgang mit

radioaktiven Stoffen gem. § 7 StrlSchV a.F. erstreckt, so

gilt diese Erstreckung als Erstreckung auf einen Umgang

nach § 12 Abs. 1 Nr. 3 StrlSchG fort (§ 197 Abs. 3 StrlSchG).

Eine Anpassung des Genehmigungsbescheides an die neue

Rechtsgrundlage ist rechtlich nicht erforderlich, da das

Gesetz dies bereits für uns macht. Dass im schriftlichen

Bescheid noch die alten “Hausnummern” stehen, ist

unschädlich. Sicherlich macht es aber Sinn, bei der

nächsten Gelegenheit (z. B. Änderung/Verlängerung der

Genehmigung) die neuen Bezüge aufzunehmen.

Zu beachten sind allerdings gewisse Spezialfälle,

in denen das StrlSchG dann doch einzelne neue

oder anspruchsvollere Genehmigungsvoraussetzungen

einführt; hier können sich die Inhaber bestehender

Genehmigungen nicht zurücklehnen, sondern sind

gefordert, innerhalb bestimmter Fristen die entsprechenden

Nachweise zu erbringen. Dies betrifft z. B.

den Umgang mit hochradioaktiven Strahlenquellen. Hier

muss bis 31.12.2020 nachgewiesen sein, dass die neue

Genehmigungsvoraussetzung des § 13 Abs. 4 StrlSchG –

Vorhandensein eines Verfahrens für den Notfall und

geeigneter Kommunikationsverbindungen – erfüllt ist,

siehe § 197 Abs. 2 S. 2 Nr. 1 StrlSchG. Ein anderer solcher

Umgangsfall betrifft die Anwendung am Menschen für

eine Behandlung mit radioaktiven Stoffen und ionisierender

Strahlung. Hier gibt es in § 14 StrlSchG teils

zusätzliche Erfordernisse; § 197 Abs. 2 S. 2 Nr. 2 und 3

StrlSchG setzt den Inhabern bestehender Genehmigungen

eine Frist (Ende 2020 bzw. Ende 2022), entsprechende

Nachweise zu führen.

Eine relevante Änderung betrifft auch Genehmigungen

nach § 16 StrlSchV a.F. für die Beförderung sonstiger

radioaktiver Stoffe. Sie gelten als Genehmigungen nach

§ 27 StrlSchG mit allen Nebenbestimmungen fort, wie

§ 204 StrlSchG anordnet; das kann allerdings für maximal

drei Jahre relevant werden, da dies die höchstmögliche

Genehmigungsdauer ist (vgl. § 16 Abs. 1 S. 3 StrlSchG

a.F.). Die Genehmigung nach § 27 StrlSchG hat die

wichtige Eigenschaft, dass sie – im Gegensatz zur alten

Rechtslage – nunmehr ihren Inhaber zum Strahlenschutzverantwortlichen

macht (§ 69 Abs. 1 Nr. 1 StrlSchG) und

in der Regel die Bestellung von Strahlenschutzbeauftragten

erfordert. Deshalb enthält § 204 Abs. 1 S. 2

StrlSchG eine Übergangsvorschrift, wonach die entsprechende

Fachkunde der Strahlenschutzbeauftragten

bis zum 31.12.2021 nachgewiesen werden muss.

Von Bedeutung ist auch das Schicksal der bestehenden

Freigaberegelungen, die teils in eigenen Freigabebescheiden,

teils in Genehmigungsbescheiden nach § 7

Abs. 3 AtG (Stilllegungs- und Abbaugenehmigungen)

niedergelegt sind. Die Werte für die uneingeschränkte

Freigabe in Anlage III Tabelle 1 StrlSchV a.F. sind in der

Neuregelung in Anlage 4 Tabelle 1 StrlSchV n.F. zum Teil

verändert wurden (sie sind nunmehr identisch mit den

ebenfalls angepassten spezifischen Freigrenzen). Was

geschieht also mit bestehenden Freigaberegelungen? Die

einschlägige Übergangsvorschrift – § 187 StrlSchV n.F. –

enthält dazu zwei Grundaussagen. Die erste: bestehende

Freigabebescheide und Freigaberegelungen in Genehmigungsbescheiden

gelten fort. Die zweite: sie gelten fort mit

der “Maßgabe”, dass die neuen Werte ab dem 1. Januar

2021 einzuhalten sind. Damit sind die Beteiligten aufgefordert,

bestehende Bescheide in den nächsten zwei

Jahren entsprechend anzupassen. Unterbleibt dies aus

irgend einem Grund, sind ab 2021 trotzdem die neuen

Werte zugrunde zu legen.

Fazit: Der Gesetzgeber hat es so eingerichtet, dass

bestehende Bescheide ins neue Recht übernommen

werden. Nur in bestimmten Fällen muss man innerhalb

einer Frist tätig werden, um Nachweise zu geänderten

Genehmigungsvoraussetzungen zu erbringen. Man wird

sehen, ob das in Einzelfällen in der Praxis zu Härten führt

und ob die Übergangsvorschriften wirklich alle denkbaren

Fälle erfassen. Im Allgemeinen aber müssten die Inhaber

von Genehmigungen (und Freigabebescheiden) mit den

neuen Regelungen leben können.

Autor

Rechtsanwalt Dr. Christian Raetzke

CONLAR Consulting on Nuclear Law and Regulation

Beethovenstr. 19

04107 Leipzig, Deutschland

Spotlight on Nuclear Law

The New Radiation Protection Law (I): Official Approvals ı Christian Raetzke


atw Vol. 64 (2019) | Issue 2 ı February

Piping Stress Analysis of Safety Injection

System of Typical PWR Power Reactor

Mazhar Iqbal, Agha Nadeem, Tariq Najam, Kamran Rasheed Qureshi,

Waseem Siddique and Rustam Khan

This paper covers the piping stress analysis of safety injection system (SIS) of Chashma Nuclear Power Generating

Station, Unit-1of electric power 325 MWe. The analysis of the safety injection system on Peps, an integrated package

which contains PIPESTRESS (the program for analysis of piping) and EDITPIPE (for preprocessing and post processing),

has been performed by dividing it into three lines. These lines have been modeled on Peps computer code using proper

input commands. To fulfill the nuclear regulatory requirements, the analysis of safety class 1 and 2 piping has been

performed using the software. Peps software has provision of stress analysis for various working conditions by defining

different load cases and combination cases as described. Peps results include the determination of loads, moments and

stress ratios at specific sections of the piping structure. This analysis confirms that piping system stresses are within

those limits specified by the ASME code.

1 Introduction

Piping in nuclear industry is different

than that of the conventional power

plant. In a nuclear power plant,

primary side involves the piping for

which the design criteria must be very

stringent and inflexible. It is because

of the reason that primary side contains

radiation source which should be

contained within the prescribed

barriers at any cost. The scope of the

nuclear industry is increasing day by

day. The power production from

nuclear energy is very common these

days. Pakistan is also producing electricity

from nuclear energy as shown in

Figure 1 [1]. In 2014 according to the

report of Nuclear Energy Institute

(NEI), 11 percent of the total electricity

production was through nuclear

energy. The current status according

to International Atomic Energy Agency

(IAEA) is that 454 nuclear reactors

are operating in the world for power

production. These are producing

401.743 GWe and many new countries

are also entering in this industry [1].

Pipes are subjected to any type of

loading which may include operating

weights i.e. pressures, temperatures

or any seismic loads i.e. earthquake.

Moreover, these weights also vary

during different stages of the plant.

For example, startup and shutdown

| | Fig. 1.

Chashma nuclear power plant (Unit 1 and 2).

stages of a plant are different than

normal operations. Similarly, emergency

conditions are very different

from normal conditions. All these

variations make a designer very careful

about the criticality of the piping

layout. Some portions of the power

plant are safety class while others are

non-safety related. These safety class

systems are further categorized into

safety class 1, 2 & 3 on the basis of

their severity. The system involved in

the conventional island are designed

and analyzed differently as compared

to those involved in the nuclear island.

The material requirements and

analysis criterion at interfaces (at

which two classes of the piping meet)

are also different [2].

2 Background

Rui Liu et.al. [3] did piping stress

analysis of nuclear piping for safety

class 2 and 3 on peps. It includes the

introduction to Peps software and the

limiting criterion for the piping stress.

The piping is safe if the stress ratio is

less than unity. Lijing Wen et. al. [4]

studied the stress analysis of reactor

coolant pump nozzle on ANSYS software.

The results show that the design

is within specified limits and satisfy

the intensity requirements for the

system. Pradeep Kumar Singh et. al.

[5] studied the stress analysis of spur

gear on ANSYS software. This paper

shows the procedure of static analysis,

boundary condition and higher

module gears are preferred if large

power is to be transferred. Q Mao

et.al. [6] studied the layout of Qinshan

reactor and evaluated the pipe layout

for pressurizer discharge system.

Z. M. Zhang et.al. [7] studied and

discussed the mechanical behavior of

nuclear piping. They performed the

analysis of safety class 1 piping on

Marc software. J. L. Dong et. al. [8]

performed the stress analysis of tubes

of a 10 MW reactor. The reactor they

considered for their analysis was a gas

cooled reactor. S. T. Dai et. al. [9]

studied and optimized the nozzle

loads for China Advanced Research

Reactor. Both static and dynamic

cases were considered and supports

were also analyzed in accordance with

code requirements. YK Tang et. al.

[10] studied the analysis of a piping

system of z-shape along with its

support failure on ABAQUS-EPGEN

code. The good response after application

of support and the dynamic

behavior of piping under different

loading combinations confirmed the

reliability of the support. J Bock et.al.

[11] studied the outcomes of omission

of piping supports and showed that

impact loadings must be taken into

consideration and a stringent criterion

must be adopted for them. B

Praneeth et. al. [12] studied the

analysis of pressure vessels using

finite element method and proved

that at very high pressure and temperature,

multi-layered pressure vessels

are better than single layer pressure

vessels. The formulas used were found

out to be very easy and simple in

comparison with other techniques.

Piping is the most important and

busiest component in any industry

and hence the piping stress analysis

becomes vital. The piping stress

analysis of safety injection system

includes both safety class 1 and class

2. The piping stress analysis of safety

injection system has not been performed

on Peps software to the

knowledge of the authors. So performing

stress analysis of this system

is a critical and novel problem.

91

ENVIRONMENT AND SAFETY

Environment and Safety

Piping Stress Analysis of Safety Injection System of Typical PWR Power Reactor ı Mazhar Iqbal, Agha Nadeem, Tariq Najam, Kamran Rasheed Qureshi, Waseem Siddique and Rustam Khan


atw Vol. 64 (2019) | Issue 2 ı February

ENVIRONMENT AND SAFETY 92

3 Safety Injection System

The relevant system to be analyzed is

Safety Injection System (SIS) of a

nuclear power plant of 300 MWe

power. It is a safety-related system so

it has no normal operation function.

Safety injection system is designed to

control the temperature of the core as

well hence providing margin in shutdown.

This can happen either in case

of primary or secondary side breakage.

Safety injection system should

maintain the temperature of the clad

| | Fig. 2.

The schematic diagram of safety injection system.

below 1200 °C and the maximum

oxidation by the reaction of the fuel

with the clad below than 16.5 % (of

total thickness) in case of any of the

accidents. The maximum hydrogen

generated should also be maintained

below one percent as described by the

regulatory body. The deformation in

geometry shape should also not

exceed the prescribed limit [13].

To fulfill regulatory requirements

all the piping system must be analyzed

according to the ASME code requirements

in our case [13].These are as

follows:

pp

NCA provides general requirements

pp

NB provides requirements for

safety class 1 equipment

pp

NC provides requirements for

safety class 2 equipment

pp

ND provides requirements for

safety class 3 equipment

pp

NE provides requirements for

concrete related components

pp

NF provides requirements for

supports

pp

NG provides requirements for

support related structures

The codes are to be satisfied in agreement

with the relevant system. These

include NCA, NB, NC, ND and NF

subsections. According to Regulatory

Guide-1.29, even in the case, there is

an earthquake; the system should

perform its function as it is a safety

system. Moreover, Regulatory Guide-

1.47 puts a very severe condition to

ensure any mitigation actions taken in

case of bypass of any protection

system. There should be a constant

monitoring in control room. The pipelines

of SIS selected for safety analysis

are high energy pipelines as working

pressure is greater than 12 MPa and

temperature is above 127 °C. The safe

shutdown earthquake (SSE), operating

basis earthquake (OBE) and these

high operating conditions make these

lines critical from the safety viewpoint.

Therefore, with the aim of satisfying

the ASME codes requirements, load

cases and their combinations have

been developed including OBE and

SSE conditions. The primary stress

intensity must meet the requirement

as given by the Equation 1 [13]:


(1)

Where,

pp

P is Pressure (design)

pp

B 1 & B 2 are Indices of primary

stresses

pp

I is the Moment of inertia

pp

D o is Pipe outer diameter

pp

t is Wall thickness (nominal)

pp

M i is the moment (due to design

loads)

pp

S m is Stress intensity (allowable)

pp

K is multiplication factor =1.5

Similarly, the primary plus secondary

stress limits must not exceed the

Case

Number

Title

of the Case

100 Operating Weight

101 Thermal Expansion

300 Earthquake

allowable limited as recommended in

ASME code.

4 Analysis on Peps

Peps is an integrated package which

contains PIPESTRESS and EDITPIPE.

PIPESTRESS is the program running

at background for analysis of piping.

The EDITPIPE in Peps is responsible

for preprocessing and post processing.

EDITPIPE runs PIPESTRESS and

related programs and follow progress

of analysis. Piping structures can be

modeled using its pre-processor and

results can be generated using its post

processor. Methodology to work on

Peps includes:

pp

Cases Definition

pp

Preparation of Input File

pp

Modeling on Peps

pp

Running the Simulations

pp

Generating the Stresses Reports

Case definition includes both load

cases and combination cases. The

preparation of an input file involves

different cards. Some of the cards and

their respective commands are:

pp

Identification Card (IDEN)

pp

Title Card (TITL)

pp

Frequency (FREQ)

pp

Load Case(LCAS)

pp

Combination Case (CCAS)

pp

Fatigue Analysis Card (FATG)

pp

Load Set Card (LSET)

Modeling on Peps includes various

commands. Some of them are:

pp

Bend Radius (BRAD)

pp

Tangent or straight pipe (TANG)

pp

Cross section (CROS)

pp

Anchor (ANCH)

After running the simulations successfully,

Peps generates the stress

reports. The safety injection system

involves all the safety class components.

Safety class one components are

those between the check valve and the

header to the reactor coolant system.

It involves the most stringent criteria

in its analysis. While the components

like centrifugal pumps, supports,

piping, accumulator, and refueling

water storage tank are categorized as

safety class two com ponents. Safety

class three involves the injection lines

of the pumps. The analysis of the

safety injection system on Peps has

been performed by dividing it into

three lines as shown in Figure 2.

| | Fig. 3.

A three dimensional model of line#01 prepared on Peps.

400

401

Operating Weight +

Earthquake

Operating Weight +

Thermal Expansion

| | Tab. 1.

Load and combination cases

for line#01 &02.

4.1 From RWST to Suction

of SI Pump

The first line is from Refuelling Water

Storage Tank (RWST) to suction of

Safety Injection Pump. Five cases i.e.

Operating Weight, Thermal Expansion,

Earthquake RG 1.60, Operating

Weight + Earthquake and Operating

Environment and Safety

Piping Stress Analysis of Safety Injection System of Typical PWR Power Reactor ı Mazhar Iqbal, Agha Nadeem, Tariq Najam, Kamran Rasheed Qureshi, Waseem Siddique and Rustam Khan


atw Vol. 64 (2019) | Issue 2 ı February

| | Fig. 4.

A three dimensional model of line#01 prepared on Peps.

| | Fig. 5.

A three dimensional model of line#01 prepared on Peps.

ENVIRONMENT AND SAFETY 93

| | Fig. 6.

Line #01 Maximum displacement for load case 100.

| | Fig. 7.

Line #01 Maximum resultant force for load case 100.

Weight + Thermal Expansion have

been defined in Table 1. The input

file was prepared on Peps and a

three dimensional model of piping

structure done on Peps is shown in

Figure 3.

4.2 From Discharge of SI Pump

to the Penetration

The second line is from discharge of

Safety Injection Pump to the penetration.

Again five cases i.e. Operating

Weight, Thermal Expansion, Earthquake,

Operating Weight + Earthquake

and Operating Weight + Thermal Expansion

have been defined as shown

previously in Table 1. The input file

was prepared on Peps and a three

dimensional model of piping structure

done on Peps is shown in Figure 4.

4.3 From Penetration

to RCS Header

The third line is from penetration to

reactor coolant system header. It

requires safety class one analysis for

which different cards in Peps have

been used e.g. load set written as

LSET and fatigue preparation card

written as FATG.

Here we need to perform its fatigue

analysis. Again five cases i.e. Operating

Weight, Thermal Expansion,

Earthquake RG 1.60, Operating

Weight + Earthquake and Operating

Weight + Thermal Expansion have

been defined as shown previously in

Table 1. The input file was prepared

on Peps and a three dimensional

model of piping structure done on

Peps is shown in Figure 5.

5 Results and Discussion

This chapter includes both results of

Peps software. The results obtained

from Peps include displacements,

resultant force, resultant moment and

stresses at each section of the piping

structure. The analysis of the safety

injection system on Peps has been

performed by dividing it into following

three lines:

5.1 From RWST to Suction

of SI Pump

All loading cases have been tabulated

separately along with their highest

stress ratios and the locations of

those points. Here only first five points

have been tabulated. Figure 6 and

Figure 7 show the maximum force

and maximum stresses on line#01

Load

Case

Title

Max. Stress

Ratio

Location

Point

Load

Case

Title

Max. Stress

Ratio

Location

Point

100 Operating Weight 0.928 47

101 Thermal Expansion 0.898 50a

300 Earthquake RG 1.60 0.198 27

400

Operating +

Earthquake

| | Tab. 2.

Summary of the Results for Line#01.

0.331 47

401 Operating + Thermal 0.936 50a

100 Operating Weight 0.473 200

101 Thermal Expansion 0.378 42

300 Earthquake RG 1.60 0.824 42S

400

401

Operating Weight +

Earthquake

Operating Weight +

Thermal

| | Tab. 3.

Summary of the Results for Line#02.

0.853 42S

0.502 42

Environment and Safety

Piping Stress Analysis of Safety Injection System of Typical PWR Power Reactor ı Mazhar Iqbal, Agha Nadeem, Tariq Najam, Kamran Rasheed Qureshi, Waseem Siddique and Rustam Khan


atw Vol. 64 (2019) | Issue 2 ı February

ENVIRONMENT AND SAFETY 94

| | Fig. 8.

Line #01 Maximum resultant moment for load case 100.

| | Fig. 9.

Line #01 Maximum stress for load case 100.

Load Case Title Max. Stress Ratio Location Point

100 Operating Weight 0.982 0

101 Thermal Expansion 0.031 5

300 Earthquake RG 1.60 0.094 0

400 Operating Weight + Earthquake 0.363 0

401 Operating Weight + Thermal 0.605 0

| | Tab. 4.

Summary of the Results for Line#03.

piping respectively. Finally, a table

is also included which summarizes

the results for complete line. The

highest stress points for load case-

100 have been shown in Table 2.

5.2 From Discharge of SI Pump

to the Penetration

Unlike line #01, here all loading cases

have not been tabulated separately.

Only a table is included which

summarizes the results for the

complete line. Table 3 includes the

maximum stress ratio for each case

and its point of location.

5.3 From Penetration to RCS

Header

Like line#02, only a table is included

which summarizes the results for the

complete line. Table 4 includes the

maximum stress ratio for each case

and its point of location.

6 Conclusions

The analysis of the safety injection

system on Peps, stress analysis tool,

has been performed by dividing it into

three lines. The first line is from

refueling water storage tank (RWST)

to the suction of safety injection (SI)

pump. The second line is from discharge

of SI pump to the penetration

while the third line starts from the

penetration and ends at reactor coolant

system (RCS) header. The analysis

of all these lines has been performed

using the software. The series of steps

followed while working on Peps

included cases definition (both load

cases and combination cases), preparation

of input file, modeling on

Peps, running the simulations and

generating the stress reports. The

preparation of an input file consists of

different cards.

The analysis of a line consisted of

different load and combination cases.

Each case was analyzed and a stress

report was generated. The stress

report included the determination of

displacements, loads, moments and

stress ratios. All the values of stress

ratio were found out to be very less

than unity. This analysis confirmed

that piping system stresses were

within the limits specified by the

ASME code.

Acknowledgement

Authors are grateful to Mr. Rizwan

Mahmood, Mr. Amjad Ali Amjad and

administration of Advanced Computational

Reactor Engineering Lab for

their kind support.

References

[1] J. R. Lamarsh, Introduction to Nuclear Engineering, 3 rd ed., 1975.

[2] F. P. Beer, R. Johnston, J. Dewolf, and D. Mazurek, Mechanics of

Materials, McGraw-Hill, 2 nd ed.: Boston, 2006.

[3] R. Liu, Z. Fu, and T. Li, “Application of Peps in Stress Analysis of

Nuclear Piping,” Journal of Applied Mathe matics and Physics, vol. 1,

p. 57, 2013.

[4] L. Wen, C. Guo, T. Li, and C. Zhang, “Stress Analysis for Reactor

Coolant Pump Nozzle of Nuclear Reactor Pressure Vessel,” Journal

of Applied Mathematics and Physics, vol. 1, p. 62, 2013.

[5] J. Venkatesh and M. P. Murthy, “Design and Structural Analysis

of High Speed Helical Gear Using Ansys,” International Journal of

Engineering Research and Applications, vol. 2, pp. 215-232, 2014.

[6] Q. Mao, W. Wang, and Y. Zhang, “The Stress Analysis Evaluation

and Pipe Support Layout for Pressurizer Discharge System,”

Nuclear Power Engineering, vol. 21, pp. 117-120, 2000.

[7] Z. Zhang, M. Wang, and S. He, “ Mechanical Analysis of the

Nuclear Class 1 Piping in HTR-10,” Journal of Tsinghua University.

Science and Technology, vol. 40, pp. 14-17, 2000.

[8] J. Dong, X. Zhang, D. Yin, and J. Fu, “Stress Analysis of HTR-10

Steam Generator Heat Exchanging Tubes,” Nuclear Power

Engineering, vol. 22, pp. 433-437, 2001.

[9] S. Dai, J. Wang, and Z. Han, “Nozzle Loads Optimization Analysis

of Outflow Primary Loop Piping in China Advanced Research

Reactor,” Atomic Energy Science and Tech nology, vol. 42, pp. 490-

494, 2008.

[10] Y. K. Tang, H. T. Tang, and M. Gonin, “Test Correlation and

Analytical Investigation of Piping Dynamic Response Including

Support Failure,” Nuclear Power Engineering, 1985.

[11] J. Bock and F. Weber, “Comparison of Stresses and Strains

Determined by Linear-Elastic and Elasto-Piastic Analysis for Piping

Systems Subjected to Dynamic Loading,” Nuclear Power Engineering,

1985.

[12] B. Praneeth and T. Rao, “Finite Element Analysis of Pressure

Vessel and Piping Design,” International Journal of Engineering

Trends and Technology- Volume 3 Issue 5-2012, 2012.

[13] A. Boiler and P. V. Code, “Section II Part D,” Properties, The

American Society of Mechanical Engineers, New York, 2001.

Authors

Mazhar Iqbal

Agha Nadeem

Tariq Najam

Kamran Rasheed Qureshi

Waseem Siddique

Rustam Khan

Pakistan Institute of Engineering

and Applied Sciences

Nilore, Islamabad, Pakistan

Environment and Safety

Piping Stress Analysis of Safety Injection System of Typical PWR Power Reactor ı Mazhar Iqbal, Agha Nadeem, Tariq Najam, Kamran Rasheed Qureshi, Waseem Siddique and Rustam Khan


atw Vol. 64 (2019) | Issue 2 ı February

Research for the Adequacy Analysis

of Plant System Behaviors During

Abnormal Conditions

Yeong Jin Yu , Ho Cheul Shin and Jae Heung Lee

Because there is no specific analytical tool for plant systems behavior in abnormal conditions, the behavior adequacy

analysis of plant systems only relies on personal experiences and knowledges of the investigator. In order to clear these

difficulties, a standardized behavior analysis method was established and specific analysis tool was developed by using

sequence of event report and alarm list of plant. Two similar events that occurred in the plants with same reactor type

were chosen to verify the established analysis method and the developed analysis tool.

As a results of verification, it was confirmed

that the behavior adequacy of

plant systems as well as identify the

systems with abnormal behaviors and

gain insights for cause analysis. Also,

the established analysis method and

the developed analysis tool were useful

for the behavior analysis of plant

systems in abnormal conditions. In

the future, standards for various plant

abnormal events and additional verification

of this method are needed to

promptly and effectively utilize the

proposed behavior analysis tool.

1 Introduction

A nuclear power plant is designed

conservatively based on the safety

analysis of design basis accidents

(DBA), such as a loss of coolant accident

(LOCA), main steam line break

(MSLB), and steam generator tube

rupture (SGTR), as well as multiple

demonstration tests. Therefore, various

abnormal events that are considered

to be less serious or severe

than DBAs are deemed to be within

the design basis that is conservative in

nature. Such a serious accident that is

used as a basis for plant design is

highly unlikely to take place during

the plant operation; however, abnormal

conditions, such as anticipated

operational occurrences (AOO), are

occasionally found during the plant

operation. Nevertheless, when these

events occur, there is no specific tools

to analyze whether plant systems are

behaving adequately as it should

according to its design. As a result, it is

not easy to determine whether the

plant systems are behaving ade quately

according to its intended design.

Against the backdrop, this research

aims to introduce a method to analyze

the adequacy of system behaviors

during abnormal situations.

2 Development

of methodology

1) Need to classify the AOPlevel

events and conduct

system behavior analysis

Table 1 shows conditions of nuclear

power plant classified by international

standard ANSI N 18.2 [1]. As for

Korea, the nuclear safety laws and

regulations specify the events and

accidents that need to be reported to

the relevant regulatory bodies, including

the ones classified according

to the aforementioned ANSI N 18.2.

As such, the events and accidents that

fall under the category are reported to

the regulatory bodies, and the regulators

are responsible for investigating

the reported events and accidents.

The initial stage of investigation is to

find out whether the system behaviors

were adequately performed or not

according to its intended design.

The behavior adequacy of systems

determined by the safety analysis of

DBAs assumes operator intervention

and an automatic actuation of safety

systems as designed to stabilize plant

condition. During the actual plant

abnormal situations, the systems do

run automatically according to the

design; however, they are also manually

operated by operators according

to the procedures written for the plant

stabilization. Although adequacy

analysis of system behaviors during

abnormal conditions is more complex

than DBA, the current analysis only

relies on personal experiences and

knowledges of the investigator as

there is no specific analytical tools for

such purpose. In order to address such

difficulties, this research paper aims

to introduce a standardized behavior

analysis method for plant systems.

2) Development of event

analysis methodology

A nuclear power plant has trip signals

to protect its reactor and control signals

to maintain the reactor stability.

When various abnormal events, such

as a reactor trip, occur, the systems are

ENVIRONMENT AND SAFETY 95

Condition I

Normal Operation and

Operational Transients

Condition II

Faults of Moderate Frequency

Condition III

Infrequent Faults

Condition IV

Limiting Faults

• Steady-state and Shutdown Operations

• Operation with Permissible Deviations

• Operational Transients, etc.

• Feedwater system malfunctions that result in a decrease in feedwater temperature

• Excessive increase in secondary steam flow

• Turbine trip, etc.

• Complete loss of forced reactor coolant flow

• Loss of coolant accidents resulting from a spectrum of postulated piping breaks

within the reactor coolant pressure boundary

• RCCA misalignment, etc.

• Main steam line break

• Main feedwater line break

• Steam generator tube rupture

• Loss of coolant accidents resulting from a spectrum of postulated piping breaks

within the reactor coolant pressure boundary, etc.

| | Tab. 1.

Classification of NPP conditions according to ANSI N18.2.

Environment and Safety

Research for the Adequacy Analysis of Plant System Behaviors During Abnormal Conditions ı Yeong Jin Yu , Ho Cheul Shin and Jae Heung Lee


atw Vol. 64 (2019) | Issue 2 ı February

ENVIRONMENT AND SAFETY 96

started by the connected protection

and control signals, and the operation

history of these safety systems is

recorded on the SOER/Alarm List.

Thus, as a means to analyze system

behaviors, this research focuses on the

SOER/Alarm List as it contains information

on actual abnormal events

that took place in the plants.

Basically, the introduced method

determines the behavior adequacy of

systems in the following manners: two

comparable events are selected and

the SOER/Alarm List of each event is

collected. Then, one SOER/Alarm List

is set as a standard point, and the

other List is moved towards the

standard point to check whether their

alarm names are matching.

The existing string-searching algorithms,

including Sing-Pattern Algorithm,

Native String Search, Knuth-

Morris-Pratt Algorithm, calculates the

percentage of matching words or

sentences in the TEXT being analyzed

as compared to a reference text.[2, 3]

However, if SOER/Alarm lists are

compared with each other using the

existing string-searching algorithms,

the result would simply be the mere

comparison of words or sentences,

rather than an insights into plant’s

physical phenomena (for example,

dead band of alarming actuation

signal, differences caused by system

scan times, etc.) and deeper understanding

of the conditions (for

example, dropping of rods in the

sequence of number 1, 2 and 3, as

compared to 2, 3, and 1). Drawing

such a simple percentage does not

help anyone to understand actual

phenomena that took place in the

plants. To address this situation, this

research p aper intends to introduce

an analysis method of comparing the

SOER/Alarm lists to get the similarity

analysis of system behaviors during

the plant abnormal conditions.

The stages of the SOER/Alarm list

comparative analysis are as follows:

pp

Compare and analyze the number

of matching alarm types between

the lists;

pp

Analyze the weighted value to be

applied on the similarity results;

and

pp

Compensate considering the total

number of alarms on the SOER/

Alarm List.

Considering the above conditions, a

computing program has been developed

in order to conduct the behavior

similarity analysis on the abnormal

plant conditions. When the SOER/

Alarm Lists recorded during the

abnormal conditions are registered into

the program, it generates the

following analysis based on Microsoft’s

Excel as well as Visual-Basic;

pp

Removal of reset alarms on the

SOER/Alarm List;

pp

Acquiring selective reset information

on the SOER/Alarm List;

pp

Arranging alarm names by time on

the SOER/Alarm List;

pp

Arranging systems by time on the

SOER/Alarm List; and

pp

Data processing programming on

the SOER/Alarm List.

3) The result of case analysis

to verify and utilize the

computer program

Two similar events were selected that

occurred in the plants with same reactor

type to apply the SOER/Alarm List

methodology, which is featured in this

research. One event involved a reactor

trip caused by a single reactor coolant

pump (RCP) shutting down, while the

other involved a reactor trip by two

RCPs stopping. Both the power plants

had a 2-loop system and the RCPs

stopped in a different loop in each

case. The result generated by using

the SOER/Alarm List methodology

and tools to analyze system behaviors

Order System Weighted Value Compensation Factor Result

1 13.8kV Power System - - -

2 Reactor Coolant System 0 % 0.5 0 %

3 Reactor Trip Switch Gear System 100 % 1 100 %

4 Control Element Drive Mechanism 100 % 1 100 %

5 Main Turbine system 87.18 % 0.886 77.27 %

6 Turbine Hydraulic Fluid 100 % 1 100 %

7 Steam Bypass Control System 100 % 1 100 %

8 Reactor Power Cutback system 100 % 1 100 %

9 Main Power System 100 % 1 100 %

10 Feed Water System 100 % 1 100 %

11 Reactor Protection System 75 % 0.8 60 %

12 Main Steam System 78.26 % 0.958 75 %

| | Tab. 2.

Analysis result on the system adequacy and similarity of two events.

of two events is featured in following

Table 2.

The analysis on the behaviors and

similarity of these two events concluded

that their system behaviors

during the transient status were

approximately 82.93 % similar. Moreover,

additional analysis on the

systems with dissimilar behaviors

revealed that there was one valve out

of many in the main steam bypass

system that was abnormal.

Based on the result of behavior and

similarity analysis of each system, the

methodology and analysis tools were

verified to be useful in analyzing

behavior adequacy and similarity of

plant systems. As the previously mentioned

result indicates, the method of

analyzing the system behaviors by

comparing similar events not only

helps in determining the behavior

adequacy of systems according to its

design, but also in identifying the

system with abnormal behavior and

conducting cause analysis so that it

can be used for the plant maintenance

activities.

3 Conclusion

The analysis result generated by using

the suggested methodology in this

research paper showed that these two

events showed a high level of similarity

in terms of their behaviors

during abnormal conditions. Furthermore,

the result found that system

behaviors were adequate, while few

systems did not behave as it is supposed

to have according to its design.

As such, by utilizing the method to

analyze similarities of events that

occurred during abnormal situations,

the behavior adequacy of plant

systems could be determined as well

as identify the systems with abnormal

behaviors and gain insights for cause

analysis. The computer program

developed as part of the research also

proved to be useful for the behavior

analysis of plant systems in abnormal

conditions. Thus, the expectation of

the safer operation of the plants would

be possible when using the analysis

methodology; it offers a prompt

and standardized behavior adequacy

analysis as well as a cause analysis

of the systems identified to have

abnormal behaviors.

4 Further study

In order to use the method suggested

in this research as an analysis tool in a

more effective and prompt way, it

would be necessary to establish standards

for various abnormal situations

and further verify this method. After

Environment and Safety

Research for the Adequacy Analysis of Plant System Behaviors During Abnormal Conditions ı Yeong Jin Yu , Ho Cheul Shin and Jae Heung Lee


atw Vol. 64 (2019) | Issue 2 ı February

establishing the standards and conducting

additional verification with

other similar events, it would be

necessary to create a foundation so

that system behaviors during various

plant abnormal events are promptly

and effectively analyzed and determined,

and the result can be used for

the plant maintenance activities.

References

[1] American National Standard Revision and Addendum to

Nuclear Safety Criteria for the Pressurized water Reactor Plants,

ANSI N18.2, (1973).

[2] Aoe, J-I.: Computer algorithms: string pattern matching

strategies, IEEE Computer Society Press, (1994).

[3] Knuth D.E., Morris(jr) J.J., Pratt V.R.: Fast pattern matching in

strings, SLAM Journal on Computing 6(1) : 323-350, (1977).

Authors

Yeong Jin Yu

Ho Cheul Shin

Korea Institute of Nuclear Safety

(KINS)

62 Gwahak-ro, Yu-seong, Daejeon,

Korea, 34142

Jae Heung Lee, Ph.D

Computer Engineering

Hanbat National University

Rep. of Korea

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Environment and Safety

Research for the Adequacy Analysis of Plant System Behaviors During Abnormal Conditions ı Yeong Jin Yu , Ho Cheul Shin and Jae Heung Lee


atw Vol. 64 (2019) | Issue 2 ı February

98

OPERATION AND NEW BUILD

Design of Control System for On-line

Ultrasonic Testing Device of Nuclear Power

Hollow Flange Bolt Based on LabVIEW

Wenchao Lu, Huibin Yang, Juan Yan and Chengbo Kang

Hollow flange bolt on-line ultrasonic testing device control system and measurement and control software are

researched and designed. It detects the fatigue damage of the hollow flange bolt of the reactor pressure vessel of the

nuclear power plant. The design, implementation and corresponding detection technology of the hardware and software

of the ultrasonic testing device control system are introduced. The control system drives the mechanical part to

detect by the five DC servo motors on the detection device. The detection process and data are displayed in real time

through the RJ45 Ethernet interface on the LabVIEW detection software interface through the new detection technology.

The research on the control system and the detection technology to realize the automation of the detection of the

hollow flange bolt of the reactor pressure vessel of the nuclear power plant.

1 Introduction

The hollow flange bolt of the reactor

pressure vessel of a nuclear power

plant is a connection fastener between

the reactor pump body and the pump

shell (Figure 1) [1]. It is easy to form

fatigue damage and is an important

vulnerable component in the working

environment of high temperature,

high pressure, high radiation and

alternating stress [2-3]. The ASME

specification and the RCC-M specification

require a full inspection of the

reactor flanged hollow flange bolt to

eliminate safety hazards and ensure

safe and reliable operation of the

nuclear power plant [4-5]. Ultrasonic

non-destructive testing (NDT) is one

of the most frequently used and fast

developing detection technologies in

this field [6], which has been widely

used in almost all industrial detection

| | Fig. 1.

Hollow flange bolt diagram to be detected.

| | Fig. 2.

On-line ultrasonic testing device for nuclear flange bolt based on LabVIEW.

fields, and has a very broad application

prospect in nuclear power

and other new technology industries

[7-8]. At present, ultrasonic testing to

detect the fatigue damage of bolt is a

trend in the current era. M.R. Sun has

independently developed a set of ultrasonic

testing system for reactor

main pressure bolt, which improves

the detection accuracy and signal- tonoise

ratio and solves the automatic

supply of coupling agent, issues such

as emissions and recycling [9].

J. Wang improved the detection sensitivity

of the screw thread tooth root

and fatigue crack by using the small

angle longitudinal wave oblique probe

ultrasonic detection method, and

effectively found the tiny fatigue crack

in the screw thread tooth root and the

internal fatigue crack [10].

As the on-line ultrasonic testing of

the hollow flange bolt in nuclear

power is mostly used manually, the

degree of automation is low, and the

accuracy of the detection data is not

high, the author based on the

LabVIEW research and designs a set of

control system for the on-line ultrasonic

testing device for the nuclear

hollow flange bolt of nuclear power.

2 Overall scheme design of

ultrasonic testing device

The on-line ultrasonic testing device

for nuclear power hollow flange bolt

based on LabVIEW mainly includes

control part, power supply part and

mechanical detection part (Figure 2).

The portable power box is connected

by an aviation plug to provide power

for the whole detection device, and

the upper computer is connected to

the water pump through the RS485

serial port by the shielded twisted pair

cable. The control part is the core of

ultrasonic detection. The upper computer

is connected through the RJ45

Ethernet interface, and the ultrasonic

detection is carried out by the aerial

plug and five DC servo motors to drive

the ultrasonic detection. The location

data of the ultrasonic flaw detection

and the defect data determined

according to the echo signal are

collected through the sensor. Realtime

data will be transmitted to the

host computer, the host computer

data analysis to determine the

damaged portion of the hollow flange

bolt and the degree of damage.

3 Mechanical structure of

ultrasonic testing device

The mechanical structure of the

on-line ultrasonic testing device for

hollow flange bolt mainly includes the

ball screw, the servo motor assembly,

the base and the supporting frame,

the water receiving tray, the foursection

track, the slides and the

detecting platform (the outer frame

assembly, the detecting trolley frame,

the detecting rod rotating mechanism,

the moving Platform.). The equipment

can meet the requirements of

ASME and RCC-M standards for ultrasonic

testing of hollow flange bolt in

nuclear power plants, and is suitable

for ultrasonic testing of various hollow

flange bolt in China. It has high safety

control performance and automatic

diagnosis of detection faults. And

immediately alert to prompt, respond

to the automatic detection requirements

of the current time.

The ball screw drives the rotating

platform of the testing tube to realize

the axial lifting motion, thus realizing

the lifting motion of the ultrasonic

testing tube and carrying out the

ultrasonic testing. The servo motor

component is composed of five DC

servo motors, which are the detecting

platform circumferential rotating

motor, the detecting platform lifting

Operation and New Build

Design of Control System for On-line Ultrasonic Testing Device of Nuclear Power Hollow Flange Bolt Based on LabVIEW ı Wenchao Lu, Huibin Yang, Juan Yan and Chengbo Kang


atw Vol. 64 (2019) | Issue 2 ı February

| | Fig. 3.

Mechanical structure diagram of on-line ultrasonic

testing device for hollow flange bolt.

motor, the detecting rod radial adjusting

motor, the detecting rod lifting

motor, and the detecting rod rotating

motor. The servo motors drive the

detection rod and the detection platform

to move, providing the original

power for the movement of the whole

system. The base and frame components

are composed of the base and

supporting frame, which provide

support for the whole mechanical

device and the checked parts (hollow

flange bolt); the four-section track is

fast connected by the fast connection

device and the positioning pin; it is

“tightly held” on the stator water

jacket by the flexible clamping mechanism;

it can be quickly fixed by

the sponge suction device and its

accessory device. The detecting platform

includes the outer frame components,

the testing car frame, the

rotating mechanism of the detecting

rod and the moving platform, and the

sliding seat includes the arc walking

mechanism, the pressing wheel, the

guide wheel and the eccentric wheel.

The outside of the sliding seat is the

guide wheel, the inner side is the

eccentric wheel, and the middle is the

pressure wheel. When the slider is

installed, the position of the eccentric

wheel makes the distance between the

left and right sides the maximum, the

sliding seat is loaded from the track

side, and then the eccentric wheel is

pressed on the orbit with the characteristics

of the eccentric wheel. The

mechanical structure of the ultrasonic

testing device is shown in Figure 3.

4 Control system of ultrasonic

testing device

The control system is the core of ultrasonic

testing, including the upper

computer and the lower computer

(motion controller). The motion controller

continuously receives the command

sent by the host computer,

drives the servo motor to perform

mechanical detection in real time, and

analyzes the ultrasonic flaw detection

position data in real time according to

the defect data determined by the

echo signal and the detection process

stage, and analyzes the data. Optimize

the transfer to the remote management

layer. When the detection

process fails, the upper computer can

timely diagnose and automatically

give an alarm prompt to effectively

ensure the safety of the ultrasonic

detection device.

4.1 Hardware design of

control system for ultrasonic

testing device

4.1.1 Hardware selection of

control system of ultrasonic

testing device

The control system of hollow flange

bolt ultrasonic testing device mainly

includes the control of testing platform,

the motion control of testing rod

and the control of ultrasonic testing

water pallet. The driver receives the

pulse signal from the motion controller

to drive the servo motor. The

servo motor converts the pulse signal

into the angular displacement driving

mechanism for testing. Select the

appropriate motion controller and

driver according to the servo motor

type, parameters, power and other

specifications. As the maxon DC motor

is a high quality DC motor, the use of

high-performance permanent magnets

brings the advantages of compact

structure, high performance and low

inertia to the driver. And because of

the small inertia, DC motor can

achieve very high acceleration, within

500 W of the high precision motor and

drive system, maxon is in the leading

position in the world. So select the

maxon DC motor.

The detecting platform circumferential

rotating motor is divided into

three stages: the start acceleration

phase (duration 0.5 s), the constant

speed phase (duration 3 s), and the

braking phase (duration 0.5 s). The

detecting platform moving speed (v)

is 0.05 m/s, the detecting platform

mass (m) is 30 kg, the gear indexing

circle diameter (d) is 120 mm, the friction

coefficient (f) is 0.05, and the

gear ratio (R) is 12.

The acceleration a:

(1)

External force of detecting platform

F r :

(2)

Detection of gear meshing force F:

(3)

Load torque T L :

(4)

m 1 is the mass of the pinion, r is the

radius of the pinion, because ½ m 1 r 2

can be negligibly small, so the load

torque can be expressed as:

(5)

Motor torque T M :

(6)

Load moment of inertia J L :

(7)

Conversion to the moment of inertia

of the motor shaft J LM :

(8)

The required detecting rod rotating

motor torque T M

> 0.09N · m and

J LM

> 0.375 kg · cm 2 the moment of

inertia .Considering the characteristics

of the maxon motor, choose type

of the detecting rod rotating motor is

maxon RE50 200W 48V.

The quality of the lifting detecting

platform includes the detecting lever,

two motor (the detecting platform

lifting motor,the detecting rod lifting

motor), belt wheel, lift floor, the total

mass (M) is 10kg, the screw dia meter

(D B ) is 25 mm, and the quality is

4.242 kg. Screw lead (P B ) is 0.02 m.

The ratio of deceleration(R) is 4.3.

The torque of detecting platform

lifting motor can be detected:

(9)

Load moment of inertia J L :

(10)

Conversion to the moment of inertia

of the motor shaft J LM :

(11)

The torque of the detecting platform

lifting motor T M

> 0.74N · m and

J LM

> 4.36 kg · cm 2 the moment of

inertia.Considering the characteristics

of the maxon motor, choose the

detecting platform lifting motor is

maxon RE50 200W 48V.

OPERATION AND NEW BUILD 99

Operation and New Build

Design of Control System for On-line Ultrasonic Testing Device of Nuclear Power Hollow Flange Bolt Based on LabVIEW ı Wenchao Lu, Huibin Yang, Juan Yan and Chengbo Kang


atw Vol. 64 (2019) | Issue 2 ı February

OPERATION AND NEW BUILD 100

Because of the small quality of the

detecting rod, combined with the

characteristics of maxon motor, the

type of detecting rod lifting motor is

maxon RE50 200W 48V.

The load (M) of the detecting rod

rotating motor is 0.3 kg, the diameter

(d) of the pulley is 80 mm, the friction

coefficient (μ) of the load and platform

is 0.6, and the deceleration ratio

(R) is 3.7.

Torque motor torque T M :

(12)

Load moment of inertia J L :

(13)

Conversion to the moment of inertia

of the motor shaft J LM :

(14)

The detecting rod rotating motor

torque T M

> 0.19N · m and

J LM

> 0.105 kg · cm 2 the moment of

inertia . Considering the characteristics

of maxon motor, choose the

detecting rod rotating motor is maxon

RE30 60W 48V.

The detecting rod radial adjusting

motor needs to radially displace the

detecting rod with a small mass and

some accessories by ±2 mm to ensure

the alignment port is detected.

Combined with the characteristics of

the maxon motor, the type of the

detecting rod radial adjusting motor is

maxon RE30 60W 48V.

According to the selected servo

motor (maxon RE30 60W 48V, maxon

RE50 200W 48V), the control system

of the ultrasonic detecting device

selects the GALIL DMC-2183 motion

controller. AMP-20540 amplifier

drives the detecting platform circumferential

rotating motor, the detecting

platform lifting motor, AMP-20440

amplifier drives the detecting rod

radial adjusting motor, the detecting

rod lifting motor, the detecting rod

rotating motor. The GALIL DMC-2183

motion controller can be used to

control 8 axes at most. It integrates

motion control and servo amplification

functions.

4.1.2 The design of the hardware

circuit of the control

system of the ultrasonic

testing device

The hardware circuit design of the

ultrasonic detection device control

system (Figure 4) mainly includes the

connection between the controller

and the motor, and the connection between

the controller and I/O. The

GALIL DMC-2183 motion controller

communicates with the host computer

through the RJ45 Ethernet interface.

The DC motor driver GALIL AMP-

20540 and AMP-20440 receive the

pulse signal from the GALIL DMC-

2183 motion controller and drive the

servo motor. The servo motor transforms

the pulse signal into the angular

displacement driving mechanism for

ultrasonic detection, and the encoder

feedback the pulse to the controller to

form the closed loop control in time.

The DC motor driver and the five DC

servo motors are connected with a set

of inductor modules to reduce the

heat of the motor, and the plug is used

as the medium of the cable in series.

The GALIL DMC-2183 motion controller

provides a universal I/O port to

synchronize with external events, 16

channels of digital input and 16

channels of digital output. To prevent

accidental damage caused by direct

connection of the main power supply

with the motion controller, the detection

device adds a relay to the I/O port

of the motion controller. The threeloop

control is realized in the motion

controller. At the same time, the

anti-interference measures such as

reliable grounding, shielding wire for

motor wire and shielding metal shell

for motor are ensured.

4.2 Software design of control

system for ultrasonic

testing device

According to the on-line ultrasonic

testing device system of hollow flange

bolt and the user’s convenience

demand, the modular programming

idea is adopted. In order to shorten

the development time, LabVIEW software

is used to write the program.

LabVIEW is mainly used in different

special toolkits and unified G language

programming methods in data acquisition,

instrument control and other

different fields [11]. In the motion

controller, the parameters such as

positioning, setting speed, setting

acceleration and so on are all pulses,

but the actual motion parameters in

the actual interface are the actual

length, the angle, and so on, the unit

is mm and degree. At the same time,

the position information obtained by

command query motion controller is

pulse, and the position information

such as mm and degree are displayed

on the interface. Therefore, to design

the conversion function, the actual

length and angle in mm and degree

will be converted into pulse, and the

pulse will be converted into mm and

degree. Taking the circumferential

rotating motor of the platform as an

example, the formula for converting

the pulse number to the rotation angle

is as follows:

motor out displacement degree =

motor in displacement pulse ·

small pitch diameter · 360

4 · reduction ratio · encoder

resolution · large pitch diameter

(15)

Figure 5 is a program block diagram

for turning the pulse number of the

detecting platform circumferential

rotating motor to the rotation angle.

The reason that the conversion

function is written in the software

instead of the fixed pulse is that the

| | Fig. 4.

Block diagram of hardware circuit design for ultrasonic testing device

control system.

| | Fig. 5.

Block diagram for turning the pulse number of the detecting platform circumferential rotating motor to

the rotation angle.

Operation and New Build

Design of Control System for On-line Ultrasonic Testing Device of Nuclear Power Hollow Flange Bolt Based on LabVIEW ı Wenchao Lu, Huibin Yang, Juan Yan and Chengbo Kang


atw Vol. 64 (2019) | Issue 2 ı February

parameters in the conversion formula

are related to the mechanical parameters,

such as the reduction ratio, the

lead of the screw, and so on. In order to

adapt to the different kind of equipment,

the software will open these

parameters and can be set up according

to different mechanical devices. The

generality of such a device is that the

conversion function calculates pulses

based on the mechani cal parameter

module. The user interface shows the

detection data classification in the

upper computer, set up the mechanical

para meter module, the motion parameter

module, automatically scan the

presupposed parameter module, the

manual scanning module, the servo

motor position and torque display

module, the servo motor switch

module, the data acquisition and

storage module. The LabVIEW controls

the main interface as shown in

Figure 6.

The functions of the software

modules are as follows:

a. Mechanical parameter module. In

order to adapt to the testing of

similar equipment in different

directions, the mechanical parameters

such as the speed reduction

ratio of the five servo motors, the

number of encoder lines, the lead

of the screw, and the diameter of

the gear indexing circle can be

customized respectively.

b. Motion parameter module. The

motion parameters such as acceleration,

speed reduction, manual

presupposition speed, automatic

presupposition speed, back zero

presupposition speed are customized

to meet the detection device at

the appropriate speed.

c. Automatic scanning of presupposition

parameters module. Automatic

scanning is based on the

motion parameters of the detecting

rod lifting motor and the detecting

rod rotating motor, and scanning

section based on the input of the

user. The detecting rod lifting

motor will move between scan

start and scan stop, and the speed

is specified by speed. The motion

range of the detecting rod rotating

motor is between scan start and

scan stop, and the rotation angle of

each cycle is step, so the number of

scavenging segments is (scan stopscan

start)/step.

d. Manual scanning module. Manual

interface is mainly used for manual

control of each axis, including

continuous movement and point

movement control. The continuous

motion control is the input relative

position and the speed of operation,

then click the button, the

motor will move to the relative

position at the set speed, and then

stop. The point control is to hold

the corresponding key, the motor

rotates according to its rotation

direction, releases the key, and the

motor stops.

e. Servo motor position and torque

display module. The operation

phase of the detection is displayed

in the main interface in the manner

of the position and torque of the

five servo motors.

f. Servo motor switch module. When

the signal light turns green, it indicates

that the servo motor has

started, is in the servo state, and

starts to move under the control of

the controller.

g. Data acquisition and storage

module. In accordance with the

requirements of the detection, the

progress of single bolt scanning

and the overall detection progress

are recorded in the upper computer

with the state of the running

bar. The root of the scavenging

section is used to judge the

damaged position of the bolt and

record the analysis in time.

5 Implementation of ultrasonic

testing process

The on-line ultrasonic testing method

for hollow flange bolts introduced in

this paper is a new type of testing

method. The mechanical detecting

device carries the ultrasonic probe to

scan from the inner wall of the hollow

flange bolt center hole by the thin

water layer contact method, and

realizes full-volume ultrasonic testing

on the threaded area of the hollow

flange bolt. After the control rod is

aligned with the inner wall of the

hollow flange bolt, the detection rod is

driven by the detecting rod lifting

motor to complete a rising scan, and

the detecting rod is driven by the

circumferential motor to rotate the

detecting rod 5°, and the detecting rod

lifting motor drives the detecting rod

to complete the lowering. A downward

scan, when reaching the bottom

of the hollow flange bolt, the detection

rod circumferential motor drive

detection lever is rotated 5° again, and

a scan cycle has been completed.

Repeat several times until the end of

the scan, a hollow flange bolt, and

then return to the starting position to

prepare to detect other hollow flange

bolts. The automatic scanning program

is written in the motion controller.

The parameters are expressed

| | Fig. 6.

LabVIEW control the main interface diagram.

| | Fig. 7.

Flow chart of automatic scanning program.

in variable form, and the upper

computer passes the assignment. And

call the program to achieve automatic

scanning. The specific detection process

is shown in Figure 7, and the

variables and their meanings are

shown in Table 1.

OPERATION AND NEW BUILD 101

Operation and New Build

Design of Control System for On-line Ultrasonic Testing Device of Nuclear Power Hollow Flange Bolt Based on LabVIEW ı Wenchao Lu, Huibin Yang, Juan Yan and Chengbo Kang


atw Vol. 64 (2019) | Issue 2 ı February

OPERATION AND NEW BUILD 102

Variable name

m4step

m4hfstep

Meaning

Motor4 step

(An angle of rotation of a sweep cycle)

m4step/2,

Motor4 half scan cycle rotation angle

m4start Start position of Motor4 =

scan start + (Scavenging section-1) * step

m3start

m3end

motor4

motor3

curseg

totseg

Start position of Motor3 (scan start)

Stop position of Motor3 (scan stop)

The detecting rotating motor

The detector rod lifting motor

Current scavenging section

Total scavenging section number

| | Tab. 1.

The variable in the automatic scanning program.

6 Conclusion

Through testing, the control system of

the nuclear hollow flange bolt on-line

ultrasonic testing device based on

LabVIEW can be automatically and

reliably detected under the required

requirements. The ultrasonic automatic

testing device and technology of

hollow flange bolt have solved the

shortcomings of the pre service and

automatic inspection of the hollow

flange bolt of the nuclear power plant

and the manual inspection, and the

defects of the detection data are not

high, the nuclear radiation, the leak

detection and so on, and the automation

of the ultrasonic inspection

has been promoted, which conforms

to the automation of the present day.

Response. The research and development

of this technology can be applied

not only to nuclear power industry,

but also to the detection of hollow

flange bolt in other industries.

Acknowledgment

We are grateful to the laboratory

equipment provided by the college of

mechanical engineering, Shanghai

University of Engineering Science.

References

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shank repair tool for defect of pressure vessel bolt hole in pressure

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Authors

Wenchao Lu

Huibin Yang

Juan Yan

Chengbo Kang

College of Mechanical and

Automotive Engineering

Shanghai University

of Engineering Science

Shanghai , China

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Operation and New Build

Design of Control System for On-line Ultrasonic Testing Device of Nuclear Power Hollow Flange Bolt Based on LabVIEW ı Wenchao Lu, Huibin Yang, Juan Yan and Chengbo Kang


atw Vol. 64 (2019) | Issue 2 ı February

Simulation of KSMR Core Zero Power

Conditions Using the Monte Carlo Code

Serpent

Yousef Alzaben, Victor H. Sanchez-Espinoza and Robert Stieglitz

1 Introduction Karlsruhe Small Modular Reactor (KSMR) core has been developed at Karlsruhe Institute of

Technology (KIT) based on the Korean System-Integrated Modular Advanced ReacTor (SMART) design [1]. A previous

investigation [2] has been accomplished for a generic SMART core based on available public data. That study concluded

the need for additional investigations. The KSMR core share many features of the SMART core, for example both have

the same number of fuel assemblies (FAs) in the core; FAs are based on 17x17 fuel pin arrays PWR proven technology;

the reactor core is loaded with low-enriched uranium fuel and cooled and moderated with light water. However, what

differentiates them is that the KSMR core is operated without boron. To compensate for high excess reactivity at

Beginning of Cycle (BOC), the KSMR core utilizes a number of burnable poison rods.

In terms of safety, the KSMR core has a

high negative Moderator Temperature

Coefficient (MTC) which is a result of

the absence of boron in the moderator.

Hence, this feature is translated

into an increased inherent core safety

performance. Nevertheless, a high

negative MTC could potentially make

the core critical even with All-Rods-

Inserted (ARI) in case of overcooling

accidents such as main steam line

break. Therefore, control rods should

be designed properly to provide

enough shutdown margin and eventually

prevent recriticality in overcooling

events.

Currently, the KSMR is planned to

have once-through fuel cycle as employed

in mPower [3]. Conceptually,

such a fuel cycle strategy has an

advantage over multi- fuel cycle by

reducing outages period due to refueling.

On the other hand, single batch

fuel loading does not effectively utilize

fuel compared to multi-batches loading

which can be noticed clearly by the

linear reactivity model [4].

The objective of this paper is to (a)

generally address the challenges facing

PWR- based SMRs core design;

predict the: (b) reactivity change from

hot to cold zero power; (c) cold shutdown

margin; (d) fuel and moderator

reactivity coefficient; and (e) 3D

assembly- wise power distribution of

the KSMR core by using the Monte

Carlo tool Serpent.

2 Used simulation tool

Serpent [5] is a dedicated reactor

physics code developed by VTT that

performs stochastic modeling of particles

using the Monte Carlo method. It

uses continues energy rather than

multi- group energy microscopic cross

sections. In which the latter relay on

an approximate self- shielding treatment

in resonance regions. Unlike

deterministic codes, Serpent has a

flexible geometrical capability which

allows high degree of accuracy to

model complex geometries. For

example, an explicit modeling of the

structures surrounding the KSMR core

(baffle, barrel, neutron pads, etc.) as

well as axial structural details (spacer

grids, end plugs, upper and lower

nozzles, etc.) were modeled to account

for their influence on core reactivity.

Serpent has the capability to accurately

represent S(α,β) thermal scattering

data for 1H at any selected temperature

through the use of linear interpolation

between S(α,β) thermal scattering

data [6]. Also, to treat cross section

temperature-dependent data by

using Doppler broadening preprocessor

that is similar to the one used

in NJOY [7]. Both features yielded

a better estimation of feedback coefficients

for the KSMR core. The Serpent

version and nuclear data library used

in the current work is 2.1.27 and

ENDF/B-VII.0, respectively. In this

work, Serpent source files have been

modified to produce legacy Visualization

Toolkit (VTK) [8] file for

post-processing purposes.

3 Core design and

model description

The design philosophy behind the

KSMR core is to adopt many proven

technology features from PWR technologies

with an emphasis of not using

soluble boron in the coolant. The

advantage of having the boron-free

operation is reflected in the elimination

of the probability of boron dilution

accidents. This issue is highly important

for severe accidents especially if

reflooding of the reactor core by seawater

is considered. In such an event,

core recriticality is mostly probable.

The KSMR core differs from advanced

PWRs (such as EPR, AP1000,

etc.) in terms of core size and fraction

of rodded FAs. The KSMR core has few

FAs in the core (57 FAs) with approximately

half of the active length (2 m)

of PWRs. Due to that, an increased

neutron leakage is expected. The

fewer number of FAs in the core leads

to fewer degrees of freedom compared

to large reactors. These two aspects

make the design of the KSMR a challenging

process. The fraction of

rodded FAs in the KSMR core is 72%

whereas in PWRs is below 50% [9].

The higher number of control rods in

the core is due to the use of boron-free

coolant. The Cold Zero Power (CZP)

and Hot Zero Power (HZP) operating

A

| | Fig. 1.

Serpent model of KSMR core.

Control Rod

Top Nozzle

A

Spacer Grids

Core Barrel

Bottom Nozzle

Core Baffle

Neutron Pad

Burnable Poison

Rod

Guide Tube

Spacer Grid

Fuel Rod

Reactor

Pressure Vessel

103

RESEARCH AND INNOVATION

Research and Innovation

Simulation of KSMR Core Zero Power Conditions Using the Monte Carlo Code Serpent ı Yousef Alzaben, Victor H. Sanchez-Espinoza and Robert Stieglitz


atw Vol. 64 (2019) | Issue 2 ı February

RESEARCH AND INNOVATION 104

conditions for the KSMR are defined

as follows:

pp

Cold Zero Power (CZP): Refers to a

pressure of 0.1 MPa with both fuel

and coolant temperatures at 300 K.

pp

Hot Zero Power (HZP): Refers to a

pressure of 15 MPa with both fuel

and coolant at 569.15 K.

The detailed Serpent model for the

KSMR core is presented in Figure 1.

4 Zero power results

The simulations performed for the

KSMR core include excess reactivity at

CZP and HZP; cold shutdown margin;

reactivity feedback coefficients; and

3D assembly-wise power distribution.

In addition, a sensitivity study was

performed to measure the influence

of core baffle, barrel, neutron pad,

spacer grids, and RPV on core

reactivity.

Due to the inherent stochastic

nature of Monte Carlo method, an

adequate number of particles were

used to establish reliable eigenvalue

and 3D assembly-wise power distribution

results. For each simulation,

fission source convergence was monitored

by Shannon entropy diagnosis

of a mesh-based fission source data.

This diagnosis led to a proper selection

of the number of inactive cycles.

For all cases mentioned above:

200,000 particles/cycle; 2,000 cycles;

and 300 inactive cycles were used.

4.1 Excess reactivity

The excess reactivity was simulated by

extracting all control rods out of the

core. Table 1 summarizes the excess

reactivity at CZP and HZP conditions.

At CZP 15,490 ±4

At HZP 8,243 ±4

Excess Reactivity (pcm)

| | Tab. 1.

KSMR core excess reactivity at CZP and HZP.

4.2 Cold shutdown margin

(CSDM)

CSDM is defined as the amount of

reactivity needed to make a reactor

core in subcriticality condition at CZP.

It is simulated by fully inserting all

(shutdown and control) rods in the

core. Taking a conservative approach,

the CSDM was calculated instead of

Hot SDM since the highest reactivity

excess is at CZP. In normal practices,

CSDM is evaluated with the highest

worth control rod stuck outside the

active core. In the KSMR core, the

CSDM with single failure of highest

control rod worth was found to be

(-6,936 ±7) pcm.

(a) Reactivity vs. Fuel Temperature

(a) Reactivity vs. Fuel Temperature

| | Fig. 2.

KSMR reactivity trends vs. (a) fuel and (b) moderator temperature.

Fuel Temperature Coefficient (pcm/K)* -2.06

Moderator Temperature Coefficient (pcm/K)* -55.04

| | Tab. 2.

KSMR fuel and moderator temperature coefficients.

* The statistical uncertainty at 1σ was found to be < 0.1 pcm/K

4.3 Reactivity feedback

coefficients

Reactivity feedback coefficients are

generally defined as a difference between

two core reactivity states per a

change in a given parameter. In this

work, it was divided into two parts:

Fuel Temperature Coefficient (FTC)

and Moderator Temperature Coefficient

(MTC). FTC is defined as the

reactivity change due to an increase of

fuel temperature per fuel temperature

change, whereas the MTC is defined

as the reactivity change due to an

increase of moderator temperature

and its corresponding density per

moderator temperature change. The

reactivity feedback coefficients were

calculated at All-Rods-Out (ARO) as

follows:

pp

Fuel Temperature Coefficient (FTC):

The moderator temperature and

density were both kept at HZP

condition (569.15 K and 0.73371 g/

cm 3 ) whereas fuel temperature was

increased from 569.15 K to 769.15 K

in 100 K step. Then, these results

were fit linearly and the FTC was

found from the slope of the fit line,

as shown in Figure 2.

pp

Moderator Temperature Coefficient

(MTC): The fuel temperature was

Normalized Power Distribution

| | Fig. 3.

3D power distribution at HZP and ARO for the KSMR core.

(b) Reactivity vs. Moderator Temperature

(b) Reactivity vs. Moderator Temperature

kept at HZP condition (569.15 K),

then both moderator temperature

and density were increased from

569.15 K (0.73371 g/cm 3 ) to

596.15 K (0.67056 g/cm 3 ) in 13.5 K

step. After that, these results were

fit quadratically and the MTC was

found by evaluating the derivative

of the fitted equation at 569.15 K,

as shown in Figure 2.

The reason behind fitting these data

quadratically is the non-linearity relationship

between moderator temperature

and density. At high temperatures

an increase in the moderator

temperature causes a larger reduction

in density compared to an identical

increase at low moderator temperatures.

The reactivity feedback coefficients

for the KSMR core are presented

in Table 2.

4.4 3D assembly-wise power

distribution

In addition to the eigenvalue simulations

at zero power, Serpent was also

used to produce 3D assembly-wise

normalized power distribution and its

associated statistical uncertainty for

the KSMR core at HZP and ARO. The

axial discretization for scoring power

Statistical Uncertainty

Research and Innovation

Simulation of KSMR Core Zero Power Conditions Using the Monte Carlo Code Serpent ı Yousef Alzaben, Victor H. Sanchez-Espinoza and Robert Stieglitz


atw Vol. 64 (2019) | Issue 2 ı February

data was set to be 20 axial regions.

Figure 3 presents the 3D normalized

power distribution and Figure 4

zooms into the hot channel (highest

power FA) axial power distribution.

4.5 Sensitivity analysis

A sensitivity study was performed on

the KSMR to study the impact of

including detailed radial and axial

structures (core baffle, barrel, neutron

pad, RPV, and spacer grids) on core

reactivity. The simulation was performed

by calculating the reactivity

worth of each of the mentioned structures

at HZP and ARO. The main

objective of this study is investigating

the worthiness of including these

structures in cross section generations.

Table 3 summarizes the outcomes

of this study.

Reactivity worth

(pcm)

Core baffle 404 ±4

Core barrel

Neutron pads

RPV

Negligible †

Spacer grids 237 ±4

| | Tab. 3.

Reactivity worth for core baffle, barrel, neutron

pad, RPV, and spacer grids.


The reactivity worth was found to be < 10 pcm

5 Discussions and

conclusions

The KSMR core design has been investigated

at (cold and hot) zero power

and BOC conditions. The carried out

investigation focused on evaluating

the inherent safety features and the

adequacy of the control system by

using the Monte Carlo tool Serpent.

The investigation process showed a

remarkable performance of the KSMR

at zero power.

The excess reactivity, CSDM, reactivity

coefficient, and power distribution

have been analyzed. The excess

reactivity of the KSMR was found to

be (15,490 ± 4) pcm at CZP, which

represents the highest possible excess

reactivity in the core at BOC. In order

to offset this large excess reactivity, a

proper control system was designed.

The control system must provide

enough shutdown margin when all

control rods in a reactor core are

inserted in order to be an effective

control system. In the KSMR core, the

shutdown margin at the highest reactivity

condition possible (CZP and

failure of highest control rod worth)

was found to be (-6,936 ±7) pcm.

| | Fig. 4.

Axial normalized power distribution at the highest power FA for the KSMR core.

This result proves the effectiveness of

the designed control system.

Since the KSMR core was designed

with boron-free moderator, the MTC

was expected to be much higher

compared to soluble boron operated

reactors. The MTC was found to be

(-55.04 ±0.10) pcm/K. This large

negative feedback coefficient may

affect the core reactivity in case of

overcooling accidents. A further investigation

is required to insure that the

control system can always provide

sufficient negative reactivity in any

possible accident scenario. The FTC of

the KSMR core revealed similar results

compared to large PWR which was

(-2.06 ±0.01) pcm/K.

The normalized power distribution

of the KSMR presented an interesting

behavior in which high power amount

was around the bottom and top of the

core. It can be noticed from Figure 3

and Figure 4 that higher power peak

is found at the bottom of the core

compared to the top of the core. This

result is due to the fact that control

rods are always presented in the top

reflector when they are fully withdrawn.

A further investigation is

suggested to demonstrate the power

peaking factor is within the acceptable

limits when control rods at

critical position and HFP condition.

Last but not the least, a sensitivity

study was performed for the KSMR

core which showed the importance of

including core baffle and spacer grids

on the calculation of core reactivity.

The outcome of this study will be used

in generating cross sections of the

KSMR. The next step of analyzing the

KSMR core is transient and HFP simulation.

The former investigation will

be possible by generating cross

sections at different fuel and coolant

temperatures to be used later in core

simulators such as PARCS or DYN3D.

The latter investigation will be

possible thanks to the KIT coupled

code Serpent-Subchanflow [10].

References

1. K. B. Park, “SMART: An Early Deployable Integral Reactor for

Multi-Purpose Applications”, INPRO Dialogue Forum on Nuclear

Energy Innovations: CUC for Small & Medium-sized Nuclear Power

Reactors, 10-14 October 2011, Vienna, Austria.

2. Y. Alzaben, V. Sanchez, R.Stieglitz, “Neutronics Safety-Related

Investigations of a Generic SMART Core with State-of-the-Art

Tools”, NUTHOS-11, Gyeongju, Korea, October 9-13, 2016.

3. M. J. Scarangella, “An Extended Conventional Fuel Cycle for the

B&W mPower Small Modular Nuclear Reactor”, PHYSOR 2012,

Knoxville, Tennessee, April 15-20, 2012.

4. M. J. Driscoll, T. J. Downar and E. E. Pilat, “The Linear Reactivity

Model for Nuclear Fuel Management”, La Grange Park, Ill., USA:

American Nuclear Society, 1990.

5. J. Leppänen, M. Pusa, T. Viitanen, V. Valtavirta, and T. Kaltiaisenaho.

“The Serpent Monte Carlo code: Status, development

and applications in 2013.” Ann. Nucl. Energy, 82 (2015) 142-150.

6. T. Viitanen, and J. Leppänen, “New Interpolation Capabilities

For Thermal Scattering Data In Serpent 2”, PHYSOR 2016, Sun

Valley, ID, May 1–5, 2016.

7. T. Viitanen, and J. Leppänen. “New Data processing features in

the Serpent Monte Carlo code.” Journal of the Korean Physical

Society, 59 (2011) 1365-1368.

8. The VTK User’s Guide, Kitware, Inc., 11th Edition, 2010.

9. J.-J. Ingremeau, and M. Cordiez, “Flexblue® core design:

optimisation of fuel poisoning for a soluble boron free core with

full or half core refuelling”, EPJ Nuclear Sci. Technol. 1, 11 (2015).

10. M. Daeubler, A. Ivanov, B. L. Sjenitzer, V. Sanchez, R. Stieglitz,

R. Macian-Juan, “High-fidelity Coupled Monte Carlo Neutron

Transport and Thermal-hydraulic Simulations using Serpent 2/

SUBCHANFLOW”, Annals of Nuclear Energy, Volume 83, September

2015, Pages 352–375.

Authors

Yousef Alzaben

Victor H. Sanchez-Espinoza

Robert Stieglitz

Karlsruhe Institute of Technology

(KIT) – Campus Nord

Neutron Physics and Reactor

Technology Institute (INR)

Reactor Physics and Dynamics

Group (RPD)

Hermann-von-Helmholtz-Platz 1

76344 Eggenstein-Leopoldshafen

Germany

RESEARCH AND INNOVATION 105

Research and Innovation

Simulation of KSMR Core Zero Power Conditions Using the Monte Carlo Code Serpent ı Yousef Alzaben, Victor H. Sanchez-Espinoza and Robert Stieglitz


atw Vol. 64 (2019) | Issue 2 ı February

Special Topic | A Journey Through 50 Years AMNT

106

SPECIAL TOPIC | A JOURNEY THROUGH 50 YEARS AMNT

Am 7. und 8. Mai

2019 begehen wir

das 50. Jubiläum

unserer Jahrestagung

Kerntechnik. Zu

diesem Anlass öffnen

wir unser atw-Archiv

für Sie und präsentieren

Ihnen in jeder

Ausgabe einen

historischen Artikel.

DAtF-KTG-Reaktortagung 1971 in Bonn

Die Reaktortagung 1971, die, wie die vorjährige Tagung in Berlin, vom Deutschen Atomforum gemeinsam mit der

Kerntechnischen Gesellschaft im DAtF abgehalten wurde, erwies sich wieder als die umfassendste Veranstaltung auf

nuklearem Gebiet in der BRD. Damit hat sich zweifellos diese Tagung, die, nach den früheren spezielleren Reaktortheorietagungen,

zum dritten Mal in dieser Form für das gesamte Reaktorgebiet abgehalten wurde, endgültig durchgesetzt.

Tagungsumfang und Teilnehmerzahl berechtigen zum Vergleich mit den alljährlichen ANS-AIF- Wintertagungen

in den USA, auch wenn diese noch wesentlich monströser sind. Außerhalb der USA hat sich die deutsche Reaktortagung

jedenfalls zur größten nationalen Veranstaltung dieser Art entwickelt.

Die Teilnehmerzahl lag wiederum höher als erwartet. Mehr

als 1500 Fachleute aus Kernforschung und -technik, aus

Energiewirtschaft und aus den Genehmigungs behörden

besuchten vom 30.3. bis 2.4.1971 in Bonn Übersichtsvorträge,

Podiumsdiskussion und die Plenarveranstaltung in

der Beethovenhalle sowie Kurzvorträge in der Universität.

Die große Hörerzahl ist nicht nur ein Kompliment für die

Organisatoren der Tagung, sondern auch ein Beweis für

das Wachsen des Feldes. Sie bereitet den Organisatoren

aber auch manchen Kummer: überraschenderweise hat

sich herausgestellt, daß in der Bundesrepublik kaum Städte

zu finden sind, in denen eine Plenarveranstaltung mit 1500

Teilnehmern und eine größere Anzahl paralleler Sitzungen

mit jeweils einigen hundert Hörern am gleichen Ort abgehalten

werden können, wie dies z. B. bei der Reaktortagung

1970 in der Berliner Kongreßhalle möglich war. In Bonn

mußten die Teilnehmer zwischen Beethovenhalle (vormittags)

und Universität (nachmittags) pendeln, wobei die

Platzverhältnisse, gemessen z. B. an der Frankfurter

Tagung, noch relativ günstig waren.

Die wissenschaftliche Leitung der Tagung hatte wieder

der Präsident der Kerntechnischen Gesellschaft, Prof. Dr.

W. Häfele, der in seiner Eröffnungsansprache auf die Fortschritte

der Kernenergieentwicklung im vergangenen Jahr

und das jetzt beschleunigte Wachstum der Kernenergiekapazität

in der ganzen Welt und vor allem auch in der

BRD hinwies. In einem Jahr, in dem mit fünf Kernkraftwerksaufträgen

mit zusammen ca. 5000 MW gerechnet

wird, von denen vier bereits jetzt bestellt oder so gut

wie bestellt sind, in dem außerdem mit dem ersten österreichischen

Kernkraftwerk ein weiterer Exporterfolg

errungen wurde und in dem sowohl von der Seite der

Versorgungssicherheit als auch von der Wirtschaftlichkeit

her die Kernenergie sich klarer denn je als Spitzenreiter

ausweisen kann, haben die Reaktorfachleute natürlich

allen Grund zum Optimismus. Kernkraftwerken kommt ja

neben steigendem volkswirtschaftlichen Nutzen und

abgesehen vom unumgänglichen Bedarf gerade auch im

Sinne der schärfer formulierten Forderungen des Umweltschutzes

große Bedeutung zu.

Die vier Veranstaltungsvormittage waren mit zwölf

Übersichtsvorträgen, einem Plenarvortrag und einer

Podiumsdiskussion ausgefüllt. An den Nachmittagen

wurden in fünf parallelen Sitzungsreihen über 200 Fachvorträge

gehalten. Man mag über die große Anzahl der

Kurzvorträge geteilter Meinung sein, ganz sicher rechtfertigt

sie jedoch der Wunsch, möglichst vielen jüngeren

Wissenschaftlern ein Podium für ihre eigenen Arbeiten zu

bieten. Daß diese Möglichkeit erwünscht ist, beweisen 374

eingereichte Kurzvorträge, aus denen 208 ausgewählt

wurden. Das Auswahlproblem, das in dieser Zeitschrift bereits

vor der Tagung diskutiert wurde (vgl. atw 4/71,

S. 169), lieferte auch während der Tagung noch vielfältigen

Gesprächsstoff. Die Kritik entzündete sich nicht

zuletzt an dem Proporz, der einer sachlichen Auswahl

offensichtlich in erster Linie im Wege steht.

Eine besonders starke Resonanz fanden die sowohl von

der Thematik her als auch in der Wahl der Referenten als

überdurchschnittlich gut einzustufenden Übersichtsvorträge,

die ihrem Zweck der interdisziplinären Information

und Kommunikation voll gerecht wurden. Ausgehend von

der zunehmenden Bedeutung der Elektrizität für unsere

Gesellschaft und von Berichten über den Stand der beiden

Reaktorbaulinien der nächsten Generation, wurde die

wegen ihrer Aktualität mit besonderer Spannung erwartete

Themengruppe über die Wechselwirkung von Kernenergie

und Umwelt, die in drei Vorträgen von der physiologischen,

technischen und Strahlenschutzseite her beleuchtet

wurde, zu einem Höhepunkt der diesjährigen Tagung.

Großes Interesse fand auch die Übersicht über die den

Reaktorfachleuten meist nicht so geläufige Nutzung

radioaktiver Stoffe. Die Vorträge des letzten Vormittags

gaben ein recht umfassendes und geschlossenes Bild über

den Stand der Brennstoffkreislaufindustrie bis hin zur

Behandlung und Lagerung der radioaktiven Abfälle. Nicht

unerwähnt sollen zwei außerhalb von geschlossenen

Themenkreisen stehende Übersichtsvorträge bleiben, in

denen zukunftsträchtige reaktortechnische Gebiete

referiert wurden, nämlich der Prozeßrechnereinsatz in

Kernkraftwerken, der bislang noch mehr oder weniger

passiv erfolgt, und das Incore-Thermionik-Reaktorprojekt,

an dem in Forschungszentren und von Entwicklungsgruppen

in der Industrie für die Energieversorgung von

Fernsehsatelliten mit großem Nachdruck gearbeitet wird.

Ein weiterer Höhepunkt der Reaktortagung, der auch

in engem thematischen Zusammenhang mit den Übersichtsvorträgen

zu Umweltschutzfragen stand, war die

Podiumsdiskussion über das Thema „Kernenergie und

Gesellschaft”. Unter der Leitung des bekannten Fernsehmoderators

R. Appel äußerten zunächst Repräsentanten

der drei Bundestagsfraktionen Fragen und Meinungen

zum Gesamtgebiet Kernenergie, die dann von Vertretern

der kerntechnischen Industrie, der Elektrizitätsversorgungsunternehmen,

des Bundesgesundheitsamtes, der

Special Topic | A Journey Through 50 Years AMNT

1971 DAtF-KTG-Meeting on Reactors in Bonn


atw Vol. 64 (2019) | Issue 2 ı February

Reaktorsicherheitskommission und des Bundesministeriums

für Bildung und Wissenschaft aufgegriffen und

beantwortet wurden. Die Teilnehmer des Panels forderten

eine noch wesentlich bessere und rückhaltlosere Unterrichtung

der Öffentlichkeit über alle Fragen der Kernenergienutzung,

insbesondere soweit sie Sicherheitsfragen

berühren. In diesem Sinne versuchten am nächsten

Tag der wissenschaftliche Tagungsleiter und zahlreiche

Teilnehmer mit Demonstranten vor Beginn der Plenarveranstaltung

über Sicherheitsprobleme in Zusammenhang

mit der Kernenergienutzung zu diskutieren. Der fruchtlose

Versuch einer Diskussion mit einer Gruppe, die überwiegend

aus dem Thema fernstehenden Frauen und

Kindern bestand, unterstreicht den guten Willen der Kerntechniker

zur sachlichen Diskussion und sollte jedenfalls

nicht zur Resignation seitens der Fachleute führen. Daß

Demonstrationen dieser Art zustande kommen, ist letzten

Endes doch wirklichem Informationsbedürfnis und

mangelnder Informationsarbeit zuzuschreiben.

Im Mittelpunkt der vom Präsidialmitglied des DAtF,

Prof. Dr. H. Goeschel, eröffneten Plenarveranstaltung

stand der Festvortrag von Dr. H. Frewer „Energieverbund

zwischen nuklearen und konventionellen Kraftwerken”.

Nachdem Prof. Goeschel darauf hingewiesen hatte, daß

von den deutschen Reaktorbaufirmen als Vorleistung in

den letzten 15 Jahren Verluste von weit über 500 Mio. DM

verbucht werden mußten, unterstrich Dr. Frewer, daß die

Sicherheitsauflagen für Bau und Betrieb der Kern reaktoren

in der Bundesrepublik einen derart perfektionierten Stand

erreicht haben, daß die internationale Konkurrenzfähigkeit

der deutschen Reaktorindustrie vor allem in

dritten Ländern bereits geschmälert sei. Zur verstärkten

Nutzung der Kernenergie in der BRD führte er aus, daß der

wirtschaftlich optimale Einsatz von Kernkraftwerken nur

durch eine integrierte Verbundoptimierung aller Energieträger

erreicht werden könne. Das Deutsche Atomforum

führte gleichzeitig mit der Reaktortagung in der

Beethoven halle eine nicht nur für die Teilnehmer, sondern

noch mehr für eine breitere Öffentlichkeit bestimmte

Ausstellung „Kernenergie – friedlich genutzt“ durch, die

ein anschauliches Bild der verschiedenen zur Kernenergienutzung

gehörenden Gebiete und Entwicklungen, vor

allem auch in der Bundesrepublik, zeigte.

Die nachfolgenden Kurzberichte über die einzelnen

Sitzungen können und sollen wieder nur Tendenzen und

nur in wenigen Fällen besonders interessierende Einzelentwicklungen

hervorheben.

1 Reaktoranalysis

Den an der Auslegung des Reaktorkerns arbeitenden

Wissenschaftlern bot sich mit 80 Vorträgen aus den

Bereichen der Physik, Sicherheit und Thermohydraulik ein

breites Spektrum an Informationen.

An dieser Stelle seien einige allgemeine Bemerkungen

und persönliche Eindrücke zur Sektion 1 festgehalten,

bezüglich Details der Einzelbeiträge sei auf die in Kürze

erscheinende Compact-Sammlung der Konferenz hingewiesen

(am Rande sei bemerkt, daß die Herausgabe und

die ansprechende Aufmachung der Compacts der Berliner

Tagung wesentlich das Ansehen der Tagung gefördert

haben dürften). Wenn man bedenkt, daß etwa 70 weitere

Anmeldungen zurückgestellt wurden, so läßt dies darauf

schließen, daß offenbar die Reaktoranalysis eine gewisse

Sonderstellung im Vergleich zu den anderen Sektionen

einnimmt. Dies ist zunächst sicher eine Folge des großen,

umfassenden Gebietes, das die Reaktoranalysis umschließt.

Es drängt sich die Frage auf, ob es sich hier nicht

| | Die Podiumsdiskussion über „Kernenergie und Gesellschaft“

auf der Reaktortagung 1971.

eher um zwei Sektionen handelt – und man sucht nach

einer möglichen Trennlinie. Würde man diese bei der

Thermohydraulik ziehen, so wären allerdings nur 11 Vorträge

der jetzigen Tagung daruntergefallen. Zweifellos

wird das gerade genannte Teilgebiet im Laufe der nächsten

Jahre ein zunehmendes Interesse finden, so daß das jetzt

vorliegende stärkere Übergewicht der Physik zurückgehen

dürfte.

Wo liegen die sachlichen Schwerpunkte der Sektion 1?

Wenden wir uns zunächst den Physikbeiträgen zu. In

der Reaktortheorie kommt zweifellos der Erstellung

mehr dimensionaler Reaktorprogramme eine zentrale

Bedeutung zu. Dies wird natürlich durch die Ver größerung

an Speicherkapazität und an Rechengeschwindigkeit

moderner Computer mit bedingt, jedoch auch durch

den Wunsch nach größerer Genauigkeit der Vorhersage

nuklearer Parameter. Berechnungen von statischen und

zeitabhängigen Neutronenverteilungen in zwei und

drei Raum-Dimensionen wurden diskutiert, ebenso

die Effektivität von Programmsystemen. Als besonders

interessant ist dem Verfasser dabei die Bestimmung

dreidimensionaler Flußverteilungen mit Hilfe von Stoßwahrscheinlichkeiten

im Gedächtnis geblieben.

Das Reaktorcore wird hierbei in Quader aufgeteilt,

wobei die Kopplung zwischen diesen über die ein- und

auslaufenden Ströme vermittelt wird.

Die theoretische Analyse schneller Reaktoren scheint

ebenfalls einen Schritt weitergekommen zu sein. Obwohl

einige noch nicht verstandene Diskrepanzen zwischen

Theorie und Experiment vorliegen und man in z. T.

beeindruckenden experimentellen Versuchsreihen dabei

ist, diese Unterschiede aufzuklären (z. B. die Bestimmung

von ß eff ), wurde z. B. bei der Analyse einer Vielzahl von

kritischen Anordnungen eine Genauigkeit in der Vorhersage

der Kritikalität von besser als 1 % erreicht. Man

hat damit also etwa die gleiche Unsicherheit wie bei der

nuklearen Analyse thermischer Reaktoren erreicht. Dieses

Ergebnis sollte jedoch nicht darüber hinwegtäuschen, daß

zufällige Kompensationseffekte durchaus noch mit im

Spiel sein können. Auf der experimentellen Seite können

die Meßverfahren in kriti- tischen Anordnungen als weitgehend

etabliert angesehen werden. Leider hörte man

nichts über die Analyse des Reaktorrauschens bei Leistung,

ein Gebiet, das einige Gruppen bearbeiten, das jedoch

offenbar nur langsam Fortschritte macht. Die breit

angelegte Versuchsreihe zur Physik von Plutonium- Uran-

Brennstoff in Leichtwassergittern ist im Hinblick auf die

Rezyklierung des Brennstoffs in thermischen Reaktoren

besonders hervorzuheben.

Der Bereich der Reaktordynamik und Sicherheit

erscheint, verglichen mit seiner Bedeutung, etwas unterrepräsentiert.

Dazu muß man beachten, daß über viele mit

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der Reaktorsicherheit verbundene Fragen auch in Sektion 2

berichtet wurde. In der Reaktordynamik werden von einigen

Gruppen mehrdimensionale ortsabhängige Neutronik-

Programme entwickelt oder auch bereits eingesetzt, während

meist auf eine entsprechend aufwendige Behandlung

thermo- und hydrodynamischer Rückwirkungen noch verzichtet

wird. Eine klar überschaubare und abgerundete

Darstellung der sicherheitstechnischen Relevanz dieser

Methoden wurde allerdings noch nicht gegeben.

In der Thermohydraulik fanden die Beiträge zur Quervermischung

des Kühlmittels und der Strömungsverteilung

um Blockaden in Rohrbündeln großes Interesse.

Hierzu ist zu sagen, daß man über eine parametrisierte

Darstellung der Vorgänge noch nicht wesentlich hinausgekommen

ist; es muß noch viel Arbeit in die theoretische

Interpretation hineingesteckt werden. Dies ist nicht sehr

verwunderlich, denn die vollständige Beschreibung der

einfacheren Probleme ohne Quervermischung ist bereits

sehr aufwendig. Schon eingangs wurde gesagt, daß dieser

Bereich der Reaktoranalysis der Wichtigkeit entsprechend

eine stärkere und dabei koordinierte Bearbeitung erfordert.

In diesem Sinne wäre auch die Bildung einer Fachgruppe

Thermohydraulik der KTG sehr zu begrüßen.

2 Reaktorbauelemente und -komponenten

In dieser Sektion, für die die Bezeichnung „Reaktorkomponenten

und -kreisläufe” vielleicht besser wäre, wurden

36 Vorträge gehalten. Davon bezogen sich etwa 14 auf

Anwendungen in natriumgekühlten, 12 in wassergekühlten

und 7 in gasgekühlten Reaktoren. Die restlichen

Vorträge lassen sich nicht ohne weiteres in dieses etwas

willkürliche Schema einordnen.

Die eigentlichen Reaktorkomponenten waren etwas

schwach vertreten. Die Gesamtzahl der Vorträge täuscht

bei dieser Beurteilung, da in der Sektion eine Reihe von

Vorträgen gehalten wurden, die ihrem Inhalt nach besser

anderen Sektionen zuzuordnen sind. So gehören z. B. die

acht Vorträge der Untersektion Kernwerkstoffe thematisch

fast ausschließlich zur Sektion 4. Die reaktorbauende

Industrie sollte ermuntert werden, aus ihrem reichen

Erfahrungsschatz gerade für diese Sektion etwas mehr

beizusteuern. Ansätze dazu waren auf dem Gebiet der

Leichtwasserreaktoren vorhanden, aber es hätte auch hier

mehr sein können.

Bei den Vorträgen, die sich mit der Natriumtechnologie

befaßten, war naturgemäß ein größerer Anteil theoretischer

Natur, wie etwa die digitale Störfallsimulierung für

das Dampferzeugersystem des SNR oder Berechnungen

zum Druckaufbau in natriumbeheizten Dampferzeugern

bei etwaigen Na-H 2 O-Reaktionen sowie Vergleiche

zwischen austenitischen und ferritischen Na/Na-Wärmeaustauschern.

Immerhin standen zumindest teilweise

Versuchsergebnisse zur Abstützung der Rechnungen oder

zum Vergleich zur Verfügung. Einen noch größeren Anteil

hatten Analysen-, Meß- und Nachweisverfahren in

Natrium kühlkreisläufen. Hier beginnen sich die Erfahrungen

mit den in Betrieb befindlichen Versuchsanlagen

auszuwirken bzw. jene Erfahrungen, die bei der

Planung und dem Bau weit umfangreicherer, noch nicht in

Betrieb befindlicher Anlagen einschließlich des KNK

gewonnen wurden. Gerade diese kurz vor ihrer Inbetriebnahme

stehenden Anlagen, die auch in einem Übersichtsvortrag

vorgestellt wurden, werden einen weiteren

wichtigen Beitrag zur Reife der Natriumtechnologie

liefern. Zwei Vorträge über Handhabungseinrichtungen

und Reinigung natriumbenetzter Teile machten deutlich,

daß auf diesem Gebiet ein großer Erfahrungsschatz

vorliegt, mit dem der vielfach als sehr problematisch angesehene

Umgang mit Natrium beherrschbar sein sollte.

Auch werden bald Großversuche mit dem Drehdeckelabdichtsystem

des SNR und der Brennelementwechselmaschine

im Natriumbetrieb beginnen.

Die mehr theoretischen Vorträge auf dem Gebiet der

wassergekühlten Reaktoren galten der Sprödbruchanalyse

von Druckgefäßen für Druckwasserreaktoren bei Kaltwasser

einspeisung zur Kernnotkühlung und den Kriterien

zur Auslegung der Sicherheitsumschließung für Siedewasserreaktoren.

Für erstere wurde mit Hilfe der Bruchmechanik

gezeigt, daß der hypothetische Störfall auch nach

einer langen Einsatzzeit des Druckbehälters nicht zu

Sprödbruchschäden an diesem führt. Der zweite Vortrag

ließ erkennen, daß bei der heute in Deutschland üblichen

Bauweise des Sicherheitsbehälters mit Druckabbausystem

zusammen mit der Anordnung des Turbinenkreislaufes im

Reaktorgebäude bei richtiger Auslegung alle denkbaren

Störfälle sicher beherrscht werden können. Die Her stellung

großer Druckgefäße und ein Vergleich von Ergebnissen

der Verfahrens- und Fertigungsprüfung bei Schweißplattierungen

solcher Druckgefäße waren Themen weiterer

Vorträge. Da nahtlos geschmiedete Flanschringe für große

Reaktordruckbehälter nur in den USA und in Japan hergestellt

werden können, schmiedet man in der BRD zwei

Halbringe und vereinigt diese durch Elektroschlackeschweißung,

über die ebenfalls berichtet wurde. Vor der

mechanischen Bearbeitung erfolgt eine Vergütung des so

geschweißten Ringes. Letzte Rundschweißnähte am

Behälter werden zum Teil aus Transportgründen auf der

Baustelle ausgeführt. Der Prüfaufwand ist beträchtlich,

jedoch erforderlich, besonders da die Erfahrungen der

Hersteller und Prüfer noch nicht allzu groß sind.

Bei den Armaturen für Druckwasserreaktoren ist ein

deutlicher Zug zur Typisierung erkennbar. Für die

Bestellung und Lagerhaltung auch auf der Baustelle wird

EDV eingesetzt. Da der Einzelprüfaufwand groß ist, wird

bei Siemens ein umfangreicher Armaturenprüfstand

erstellt, der es gestattet, alle Armaturen bei Betriebsbedingungen

zu testen. Für die Dampfleitungen bei Siedewasser

reaktoren werden neuerdings eigenmediumsbetätigte

Schnellschlußarmaturen eingesetzt, die mit

einer noch höheren Sicherheit schließen als die bisher verwendeten.

Die Erfahrungen mit den Hauptkühlmittelpumpen

von Druckwasserreaktoren (ähnliches gilt auch

für Siedewasserreaktoren) haben gezeigt, daß mit der

Bauart „Außenliegender angeflanschter Motor und

berührungsfreie, hydrostatisch wirkende Wellendichtung”

Laufzeiten von 20.000 h erreicht werden. Zur Messung des

Neutronenflusses in Reaktoren wurde ein Verfahren mit

Wechselstromkanal und Kreuzkorrelation entwickelt,

welches gestattet, beim An- bzw. Abfahren den Fluß über

7 1/2 Dekaden mit der gleichen Anordnung linear zu

messen. Für die Erfassung der Neutronenflußverteilung in

großen Cores wurde ein sehr interessantes Meßverfahren

vorgestellt, welches beim KKS (Stade) in Kombination mit

dem Prozeßrechner gestattet, innerhalb von 10 Minuten

eine komplette Flußverteilung an 32 über den Querschnitt

des Cores verteilten Positionen und über die gesamte

Länge des Cores zu ermitteln. Das System soll nachträglich

auch in Lingen eingebaut werden.

Auf dem Gebiet der gasgekühlten Reaktoren wurde

u. a. über eine in Ispra entwickelte Innenisolierung für

Spannbetonbehälter berichtet. Es wird schwierig sein,

dieses Konzept industriell einzuführen, da in Westeuropa

und den USA bereits Erfahrungen mit etwas anderen

Systemen vorliegen. Für den THTR in Schmehausen

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werden auf Grund einer Zuverlässigkeitsanalyse linear in

den Kugelhaufen einfahrbare Abschaltstäbe einem spiralbohrerähnlichen

Drehstabkonzept vorgezogen. Die

Regelung des Gasmassenstromes wird beim THTR über

Frequenzsteuerung der integrierten Asynchronmotoren

vorgenommen, wobei die Frequenzgeneratoren von drehzahlsteuerbaren

Dampfturbinen angetrieben werden.

Andere Regelungsmöglichkeiten wurden diskutiert. Bei

Langzeitversuchen an Dampferzeugermaterialien in einer

für einen HTR repräsentativen Gasatmosphäre wurden

keine Kohlenstoffablagerungen festgestellt, obwohl Ha-

Diffusion auftrat. Anhand von wärme- und strömungstechnischen

Untersuchungen in Luft und Helium unter

höheren Drücken wurden Vorteile von schraubenförmig

gewendelten Rohrpaketen mit gleichbleibender kleiner

Längsteilung für Dampferzeuger herausgestellt. Die Einhaltung

gewisser Wandabstände ist für eine gleichmäßige

Gasabkühlung von großer Bedeutung. Bei Graphiteinbauten

lassen sich durch Pyrokohlenstoffschichten an

der Oberfläche und in den Poren die Korrosions- und

mecha nischen Eigenschaften erheblich verbessern. Als

Pyrolysegas ist Propan günstiger als Methan. Rechnungen

zeigten, daß bei hohen Temperaturen (ab 950 °C) und Vorhandensein

von Spannungen Ha in den Graphit ein dringen

und mehrere mm unter der Oberfläche durch Korrosion

von C eine Vermorschung hervorrufen kann, so daß evtl.

später Stücke der Oberfläche ausbrechen können. Ein Verfahren

zur Bestimmung der Kühlmitteigeschwindigkeit

mit Hilfe von korrelierten Thermoelementsignalen ist für

verschiedene Fluide anwendbar.

In der Untersektion Kernwerkstoffe befaßten sich

mehrere Vorträge mit technologischen Fragen wie Ausscheidungsverhalten,

Verträglichkeitsbedingungen mit

dem Brennstoff und dem Kühlmittel, Festigkeitseigenschaften,

Einfluß der Neutronenbestrahlung (Hochtemperaturstrahlungsversprödung)

bei Hüllrohrwerkstoffen für

natrium- und dampfgekühlte Reaktoren. Hauptsächlich

wurden hochwarmfeste austenitische Stähle und Superlegierungen

aus den Inconel-, Incoloy- und Hastelloyreihen

diskutiert. Weiterhin wurde gezeigt, daß längsnahtgeschweißte

Zircaloy-Hüllrohre nahtlos gezogenen gleichwertig

sein können, und eine Methode zur zerstörungsfreien

Bestimmung von niedrigen HJ-Konzentrationen in

Metallen, angewendet auf die Diffusion von Ha in Zircaloy-

Yttriumkombinationen, vorgestellt. Mit dem Problem der

Fertigung von Abstandshaltern für stabbündelförmigc

Brennelemente befaßte sich ein weiterer Vortrag.

3 Bau und Betrieb

von kerntechnischen Anlagen

In der Sektion 3 wurden die Themen „Reaktorbetriebserfahrungen”,

„Sicherheit und Umwelt”, „EDV in der

Kerntechnik” und „Wiederholungsprüfungen” behandelt.

In rasch wachsendem Maße fallen auch in der BRD

Betriebserfahrungen an. Dementsprechend nahmen die

diesem Thema gewidmeten Kurzvorträge einen breiten

Raum ein. Ein zentrales Thema bei den zusammenfassenden

Darstellungen über die bisherigen Betriebserfahrungen

mit Leichtwasserreaktoren stellte das Verhalten

der Brennelemente dar. Sowohl Wirtschaftlichkeitsfragen

im Zusammenhang mit der betriebsnahen Brennelement-

Einsatzplanung als auch die bisherigen Erfahrungen mit

Brennelemenlschäden wurden ausführlich diskutiert.

Die Planung des BE-Einsatzes unterliegt Forderungen,

die einerseits aus dem Energieversorgungssystem, in das

das Kraftwerk integriert ist, andererseits aus dem Kraftwerk

selbst gestellt werden. Welche Betriebsvariablcn zu

berücksichtigen sind und wie die BE-Einsatzplanung den

Erfordernissen kurzfristig angepaßt werden kann, wurde

an typischen Beispielen für beide Leichtwasserreaktortypen

beschrieben. Besonders hingewiesen wurde auf die

Möglichkeiten einer Verlängerung der reaktivitätsbedingten

Zyklusdauer bei Siedewasserreaktoren unter

weitgehender Erhaltung der Lastwechselflexibilität.

Eine Verkürzung der durch BE-Wechsel und parallel

dazu laufende Inspektions-, Wartungs- und Reparaturarbeiten

bedingten – in der jährlichen Verfügbarkeit nicht

erfaßten – Stillstands-Zeiten erscheint durch langfristige

Planung, betriebsmäßige Maßnahmen und Berücksichtigung

bei der Aus legung von Systemen möglich. In den

Vorträgen wurden Einzelheiten solcher Maßnahmen, z. B.

auch in bezug auf die Verbesserung der Gerätetechnik und

der Ausstattung der Kernkraftwerke, mitgeteilt.

In einer überraschend großen Zahl von Vorträgen

wurde das Thema Brennelementschäden aufgegriffen. Die

rasche Aufklärung der bisher in deutschen Reaktoranlagen

bekanntgewordenen BE- Schäden hat zwar auch sicherheitstechnisches

Interesse; die intensiven Bemühungen

der Industrie um diesen Problemkreis sind jedoch vor

allem wirtschaftlich begründet: Der deutliche Trend zu

großen Leistungseinheiten zwingt zur Erhöhung der

Leistungsdichte in Reaktorkernen. Ein vertieftes Verständnis

des komplexen Zusammenspiels der Schadensursachen

ist deshalb notwendig. Hierzu wurden die in den

vergangenen Jahren erzielten Fortschritte aufgezeigt.

Weitere Vorträge befaßten sich mit Versuchen zur Verkürzung

des Anfahrvorganges durch Synchronisation und

Belastung der Turbine vor Erreichen des Reaktornenndruckes,

mit den Mechanismen, die den Änderungen der

Kühlmittelaktivität bei Variation der Reaktorbetriebsbedingungen

zugrunde liegen, sowie mit den Ursachen für

Reaktorschnellabschaltungen. Letztere liegen vornehmlich

im konventionellen Teil. Die jährliche Verfügbarkeit

der Kernkraftwerke nähert sich den Werten für konventionelle

Kraftwerke.

Bei den Betriebserfahrungen mit der SNEAK stand die

Pu-Kontamination und ihre Beherrschung im Mittelpunkt

der Darstellung. Ergebnisse von experimentellen und

theoretischen Untersuchungen aus dem KFZ Karlsruhe

ergänzten den Bericht. Die wohl umfangreichsten

Betriebserfahrungen liegen bei den Anlagen AVR und

MZFR vor. Vertreter der AVR berichteten über Experimente

zum Langzeitverhalten des AVR bei simulierten

Störfällen. Die Ergebnisse veranschaulichten erneut die

bekannten sicherheitstechnischen Vorzüge dieses Reaktortyps.

Weitere Vorträge waren der Handhabung der kugelförmigen

Brennelemente des AVR gewidmet. Die Geräte

zur Handhabung waren zum Teil aufgrund von Betriebserfahrungen

entwickelt worden. Obwohl der MZFR in den

vergangenen Jahren mit einigen Schwierigkeiten zu

kämpfen hatte, haben die mit dem Betrieb des MZFR

gewonnenen positiven Erfahrungen mit dazu geführt, daß

in Argentinien das Projekt Atucha realisiert wird. Die

für einen wirtschaftlichen Betrieb von D 2 0-Reaktoren

wichtigen Fragen des BE-Wechsels und des H 2 O-Verlustes

standen im Vordergrund der Vorträge über den MZFR.

Beim Themenkreis Sicherheit und Umwelt berichteten

Vertreter des KFZ Karlsruhe über die Umweltbelastung

durch ein natriumgekühltes Schnellbrüter-Kraftwerk und

Sicherheitsprobleme der technischen Radiochemie auf

Grundlage der WAK. Der Problemkreis Sicherheit und

Umwelt kam, gemessen an der Bedeutung, die diesem

Thema international allgemein beigemessen wird,

eindeutig zu kurz.

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| | Atomgegner demonstrierten vor der Beethoven-Halle

(Bonn, Reaktortagung 1971).

Die Darstellungen über die Verwendung der EDV in der

Kerntechnik widmeten sich dem passiven Einsatz der Prozeßrechner

im Kernkraftwerk KRB sowie Entwicklungsarbeiten

im Rahmen des OECD-Programmes in Halden

(Norwegen). Die Entwicklungsarbeiten zielen auch auf

den aktiven Einsatz von Prozeßrechnern ab, z. B. bei der

Regelung des Reaktors und bei der Erfassung von den

Reaktor gefährdenden Situationen. Ein weiterer Vortrag

behandelte den Prozeßrechnereinsatz für hoch mechanisierte

Fertigungen am Beispiel der Brennstabfertigung.

In den vergangenen Jahren sind erhebliche Anstrengungen

unternommen worden, Methoden zur wirkungsvollen

Wiederholungsprüfung von Komponenten in Kernenergieanlagen

zu entwickeln. Die Themen behandelten

die Vor-Ort-Prüfung von hochwirksamen Schwebstoffiltern

und die Methoden sowie Ergebnisse der ersten

wiederkehrenden Inspektion des Reaktordruckbehälters

KWO. Erheblicher Aufwand wurde getrieben, um die

von der Industrie entwickelten US-Meßtechniken sowie

optische Prüfverfahren an die speziellen Gegebenheiten

anzupassen. Für eine auch nur andeutungsweise erschöpfende

Darstellung der bei den wiederkehrenden

Inspektionen erhaltenen Ergebnisse und für die daraus zu

ziehenden Schlußfolgerungen fehlte wohl die erforderliche

Zeit.

4 Brennstoffkreislauf

Von insgesamt 48 Vorträgen befaßten sich 28 Vorträge mit

den wissenschaftlichen Grundlagen, der Technologie und

den Betriebserfahrungen von Brennelementen. Die

übrigen Vorträge verteilten sich auf den Bereich des

Brennstoffkreislaufes. Dazu sind sinngemäß noch praktisch

alle acht Vorträge der Sitzung „Kernwerkstoffe” aus

der Sektion 2 zu rechnen. Die meisten dieser Vorträge

wären fachlich wohl zweckmäßiger mit bei der Sektion 4

einzuordnen gewesen. Der Überblick über diese somit

recht breit angelegte Sektion wurde allerdings durch die

zeitweise bis zu 3 Parallel sitzungen erschwert, überdies

entstand der Eindruck, daß eine Konzentrierung auf

ausgewählte Teilgebiete dieses breiten Gesamt-Themenkreises

innerhalb einer solchen Tagung für einige

Sondergebiete (z. B. Wiederaufbereitung) noch besser den

technisch-wissenschaftlichen Stand hätte hervortreten

lassen. Diese Schwerpunktauswahl müßte dann natürlich

von Jahr zu Jahr wechseln.

An den Sitzungen über das Gebiet Brennelemente für

Wasserreaktoren sollte hervorgehoben werden, daß nunmehr

in zunehmendem Maße Bestrahlungsresultate aus

den in Deutschland nach kommerziellen Maßstäben in

Betrieb befindlichen Kernkraftwerken zur Diskussion

gestellt werden. So fand ein Referat über Nach bestrahlungsuntersuchungen

an Zircaloy-2 als Hüllmaterial

aus den Siedewasserreaktoren VAK und KRB entsprechende

Beachtung. Besonderes Interesse verdienen

auch die referierten Resultate über Ergebnisse zum

thermischen Kriechen von plutoniumhaltigen oxidischen

Brennstoffen.

Auf dem Gebiet der Brennelemente für schnelle

Reaktoren interessieren vor allem die sich verdichtenden

Hinweise auf die möglicherweise abbrandbegrenzende

Bedeutung der chemischen Wechselwirkung zwischen

höher abgebranntem Brennstoff und der Hülle. Die Referate

zum Hüllwerkstoffverhalten (in Sektion 2) und zu

einigen speziellen Brennstoffproblemen brachten weitere

wissenschaftlich interessante Details, die im wesent lichen

bereits bekannte Vorstellungen weiter festigten. Aus

einigen wenigen Referaten über fortschrittliche Hochleistungsbrennstoffe

sind interessante Ansätze für die

weitere erforderliche Entwicklungsarbeit erkennbar.

Der Stand der Entwicklung von Brennelementen für

Hochtemperaturreaktoren ergab sich aus den sehr übersichtlich

angelegten Referaten über die Fortschritte bei der

Brennelementherstellung für den THTR sowie über den

Stand der Bestrahlungserfahrung, insbesondere das Bestrahlungsverhalten

der AVR-Brennelemente, die eine für

den Reaktorbetrieb unerwartet günstige Entwicklung der

Spaltgasfreisetzung aufwiesen. Mehrere Referate über

mehr grundlagenorientierte Untersuchungen zum Spaltproduktverhalten

von HTR-Brennstoffen demonstrieren

allerdings auch den heute noch aufgewendeten Untersuchungsumfang

auf diesem Gebiet.

Unter den Referaten über Brennelemente für andere

Reaktoren beeindruckte bei den modernen MTR-

Elementen der erforderliche fertigungstechnische Aufwand,

bei der Technologie der ITR-Brennelemente die

Vielseitigkeit interessanter Detailprobleme. Unter dem

Titel Brennstoffkreislaui und Anreicherung interessierte

besonders eine ausführliche Analyse gegenwärtiger und

zukünftiger Brennstoffkreislaufkosten von Leichtwasserreaktoren.

Die beiden in Deutschland zur Zeit im Aufbau

befindlichen Verfahren zur Anreicherung – einerseits nach

dem Trenndüsenverfahren, andererseits mittels Zentrifugen

– stehen beide im Stadium der Errichtung von

Anlagen unter wirtschaftlichen Aspekten. Die der Öffentlichkeit

leichter zugänglichen Arbeiten am Trenndüsen

verfahren schilderten den abgeschlossenen Aufbau der

Prototypen der größeren Trennstufen. Seitens des Zentrifugenverfahrens

überwogen mehr theoretische Wirtschaftlichkeitsbetrachtungen.

Auf dem Gebiet der Wiederaufarbeitung konzen trierten

sich die Referate und Diskussionen auf die Probleme beim

Brennstoff schneller Brutreaktoren und von Hochtemperaturreaktoren.

Die halbtechnische Miniaturextraktionsanlage

in Karlsruhe ist nahezu betriebsbereit, die entsprechende

Anlage in Jülich hat noch nicht dieses Stadium

erreicht.

Von den vier Referaten zur Spaltstoffkontrolle dürfte

insbesondere ein Referat von Vertretern der IAEO interessieren,

das die heutige Auffassung dieser Organisation zu

diesem auch mit politischen Problemen belasteten Fragen

hier widerspiegelt. Aus Karlsruhe wurden Vorstellungen

über ein rationelles Überwachungssystem der in Frage

kommenden Anlagen beigesteuert.

Aus der Sitzung Prozeßinstrumentierung und Behandlung

radioaktiver Abfälle interessiert naturgemäß

besonders das zweite Thema. Ein Referat brachte jedoch

Special Topic | A Journey Through 50 Years AMNT

1971 DAtF-KTG-Meeting on Reactors in Bonn


atw Vol. 64 (2019) | Issue 2 ı February

auch interessante Aspekte zur automatischen Überwachung

von Aufbereitungsanlagen. Zur Behandlung radioaktiver

Abfälle kann das erfreuliche Resümee gezogen

werden, daß heute ein System von Maßnahmen und Einrichtungen

existiert, das es erlaubt, den bereits in größeren

Mengen anfallenden niedrig und mittel aktiven Abfall zu

verarbeiten und auch bei sehr hohen Ansprüchen an die

Sicherheit einer Endlagerung zuzuführen. Dieses Stadium

ist für den hochaktiven Abfall noch nicht erreicht. Allerdings

rechnet man mit einer erheblichen Steigerung des

Anfalls erst ab etwa 1980.

5 Reaktorkonzepte und

Wirtschaftlichkeitsfragen

In dieser Sektion wurden von 36 eingereichten Vorträgen

19 in das Programm aufgenommen und 16 auf der Tagung

vorgetragen.

Vorherrschend bei den einzelnen Vorträgen war die

Darstellung von Reaktorkonzepten; Fragen der Wirtschaftlichkeit

wurden wenig oder gar nicht behandelt. Alle Ausführungen

bezogen sich auf Reaktoren fortgeschrittener

Bauart bis hin zu dem futuristischen Konzept des Fusionsreaktors.

Einige Vorträge über die Wirtschaftlichkeit, vor

allem der bestehenden Reaktorgeneration, waren anderen

Sektionen zugeordnet, was die Übersicht etwas erschwerte.

Wirtschaftlichkeitsfragen der Kernenergie allgemein

wurden nur in einigen Übersichtsvorträgen angesprochen.

Einen breiten Raum haben naturgemäß die Schnellen

Brutreaktoren und die Hochtemperaturreaktoren eingenommen,

die als fortgeschrittene Reaktorkonzepte in

Deutschland gleichrangig entwickelt werden. Leider sind

beide Vorträge über das Konzept natriumgekühlter Schneller

Brutreaktoren der SNR-Linie ausgefallen, so daß der

Übersichtsvortrag über den „Stand der Entwicklung des

Schnellen natriumgekühlten Reaktors (SNR)” die einzige

Informationsquelle über dieses Reaktorkonzept auf der Tagung

darstellte. Das ist umso bedauerlicher, als die gerade

in den letzten Wochen und Monaten in verstärktem Maße

geführte Diskussion über den Natriumbrüter das große Interesse

an diesem Reaktortyp gezeigt hat; so wurde eine

ausgezeichnete Plattform für sachliche Information nicht

ausreichend genutzt.

Die beiden noch verbleibenden Vorträge über natriumgekühlte

Reaktoren befaßten sich mit für Karbid-Brennstoff

geeigneten Brennelementkonzepten und mit der

Brennelementhandhabung bei dem geplanten Forschungsreaktor

FR3.

Eine große Zuhörerschaft fand K. Wirtz bei seinem

Vortrag über Gasgekühlte Schnelle Brutreaktoren vor.

Wirtz bezog sich auf das inzwischen fertiggestellte

deutsche Memorandum zur Gaskühlung Schneller

Reaktoren und hält danach die 1. Generation des Gasbrüters

(mit Dampfturbine und Oxidbrennstoff in Stahlhülle)

nicht für eine Folgegeneration oder eine sogenannte

„back-up”-Lösung des Natriumbrüters, sondern für einen

Wettbewerber, da dieser in hohem Umfange auf die

bisherigen Entwicklungen beim Natriumbrüter (nukleare

und neutronische Untersuchungen und Brennelemententwicklung)

und beim HTR (Druckgefäß, Gebläse,

Wärmetauscher) zurückgreifen kann.

Zwei weitere Vorträge über gasgekühlte Brutreaktoren

erläuterten das Brennelementkonzept, die Coreauslegung,

das Anlagenkonzept, die Sicherheit und Wirtschaftlichkeit

der im Rahmen des Memorandums untersuchten

Varianten gasgekühlter Reaktoren.

Der Vortrag und die Diskussion über den THTR 300

zeichneten sich durch viele Details aus, von denen einige

sonst im allgemeinen nicht öffentlich genannt werden. So

wurde z. B. die Poenale je Monat Lieferverzug mit

0,75 Mio. DM, die Poenale bei Nichterfüllung des Auftrags

mit 20 Mio. DM beziffert. Die im Juli 1970 ausgesprochene

Bauabsichtserklärung (Letter of Intent) ist seit Dez. 1970

rechtsgültig; mit der Vertragsunterzeichnung wird für Mai

1971 gerechnet. Nach einer zehnmonatigen Bauvorlaufzeit

soll die vertragliche Lieferzeit am 1.10.1971 beginnen

und am 1.11.1976 enden. Die Gesamtkosten einschließlich

Kernbrennstoff, bauzuge höriger Forschungs- und Entwicklungsarbeiten,

Eigen leistungen des Bauherrn sowie

Bauzinsen werden 690 Mio. DM betragen. Neben der

Stromerzeugung werden auch der Erzeugung von Prozeßwärme

aus HTR gute Chancen eingeräumt. Dies gilt

besonders dann, wenn sich der rasche Preisanstieg fossiler

Energieträger fortsetzt. Im Hinblick auf dieses Marktpotential

wurden von Jülicher Seite bereits recht detaillierte

Vorstellungen zur Äthylenerzeugung mittels HTR

vorgetragen.

Erstmals auf einer Reaktortagung wurde über Konzepte

von Incore-Thermionik-Reaktoren (ITR) und Fusionsreaktoren

berichtet. Der ITR kann wegen seiner sehr hohen

Anlagekosten nicht mit kommerziellen Kraftwerken

konkurrieren, er eignet sich jedoch wegen seines geringen

Gewichts und des Fehlens beweglicher Teile zur Energieversorgung

von Satelliten. Die Ausgangsleistung kann von

20 kW el ohne große Mehraufwendungen auf 150 kW el

gesteigert werden. Im Leistungsbereich unter 20 kW el

konkurriert der schnelle Wärmerohr-Thermionik-Reaktor

mit dem ITR; über dieses Reaktorkonzept wurde ebenfalls

berichtet.

Die möglichen Reaktorkonzepte eines Fusionsreaktors

wurden in einer sehr übersichtlichen Zusammenfassung

dargestellt. Dabei wurden auch einige der Probleme

deutlich gemacht, die zur Verwirklichung der kontrollierten

Kernfusion noch gelöst werden müssen. Neben den

Stabilitätsproblemen der Einschließung des Plasmas und

der Leistungsregelung werden es vor allem Materialprobleme

sein, die die Materialprobleme der Spaltreaktoren

weit in den Schatten stellen. Als Beispiel wurde

die Behälterwand des plasma-erfüllten Ringraumes

genannt, die bei einer Temperatur von 1000 °C einer intensiven

Bestrahlung durch Neutronen von 14 MeV bis zu

einer Dosis von einigen 10 23 n/cm 2 ausgesetzt ist.

Zur Lösung der Materialprobleme wurden Bestrahlungen

in möglichst schnellem Neutronenfluß bis zu

hohen Dosen als vordringlich bezeichnet. Eine hohe Dringlichkeit

für die Entwicklung von Fusionsreaktoren ist

jedoch nach Meinung des Berichterstatters nicht gegeben,

da einerseits die Spaltreaktoren (einschl. Brutreaktoren)

den Energiebedarf der Menschheit bis weit über das Jahr

2000 hinaus werden decken können und andererseits ein

wirtschaftlicher Vorteil der Fusionsreaktoren (trotz der

niedrigen Brennstoffkosten) noch nicht in Sicht ist.

In der Diskussion wurde vorgeschlagen, den Lithium-

Brutmantel mit einem U-238-Brutmantel als Neutronenvervielfacher

zu kombinieren. Dabei käme gleichzeitig die

hohe Energieausbeute einer U-238-Spaltung (ca. 200 MeV

gegenüber 17,5 MeV bei einer D-T- Fusionsreaktion) dem

Prozeß zugute.

Berichterstatter

Sektion 1: H. Küsters, Karlsruhe

Sektion 2: F. Scholz, Jülich

Sektion 3: H. J. Lehmann und A. Tietze, Köln

Sektion 4: H. Weidinger, Großwelzheim

Sektion 5: D. Faude und G. Woite, Karlsruhe

111

SPECIAL TOPIC | A JOURNEY THROUGH 50 YEARS AMNT

Special Topic | A Journey Through 50 Years AMNT

1971 DAtF-KTG-Meeting on Reactors in Bonn


atw Vol. 64 (2019) | Issue 2 ı February

112

Inside

WiN Germany

KTG INSIDE

Highlights zum Jahreswechsel

Die Mitgliederversammlung 2018 von WiN Germany

(Women in Nuclear) fand am Standort der For schungs-

Neutronenquelle Heinz-Maier-Leibnitz (FRM II), auf dem

Gelände des Forschungszentrums in Garching statt.

Prof. Dr. Peter Müller-Buschbaum, wissenschaftlicher

Leiter des FRM II und Dr. Anton Kastenmüller, technischer

Leiter, begrüßten die WiNers herzlich und gaben einen

Überblick über die Geschichte der Forschungsreaktoren

und die Aktivitäten am FRM II. Vier Mitarbeiterinnen in

Führungsfunktionen stellten ihre Funktionen sowie auch

ihre sehr unterschiedlichen Karrierewege vor.

Im Rahmen der Mitgliederversammlung feiert WiN

Germany zudem ihr 10-jähriges Vereinsjubiläum. Dr. Ralf

Güldner, Präsident des DAtF, hielt die Festrede zum Gala-

Abend. Er betonte, dass Frauen eine

wichtige Rolle in der internationalen

Nuklearindustrie sowie bei Forschung

und Entwicklung einnehmen. „Qualifikationen,

Mut und Engagement sind

die Türöffner für die Karrieren von

Frauen in unserer Branche“, betonte er.

Neu gewählt wurde auch der Vorstand,

den jetzt Martina Etzmuß

( Finanzen und Spenden), Irmie

Niemeyer (Bildung), Chantal Greul

(Präsidentin), Karin Reiche (Kommunikation)

und Jutta Jené (Sprecherin)

bilden. Jutta Jené hat ihr Amt als

Präsidentin nach 6 Jahren zur Ver fügung gestellt. „Ich

freue mich sehr, den Vereinsvorsitz an Chantal weitergeben

zu können. Sie wird frischen Wind bringen, was einem

Verein immer gut tut“, hob sie bei ihrer letzten Rede als

| | Dr. Ralf Güldner, Präsident des DAtF, während

seiner Festrede im Rahmen des 10-jährigen

WiN-Jubiläums.

| | Der neu gewählte Vorstand von WiN Germany: Von links: Martina Etzmuß

(Finanzen und Spenden), Irmie Niemeyer (Bildung), Chantal Greul

(Präsidentin), Karin Reiche (Kommunikation), Jutta Jené (Sprecherin).

| | Die schwedischen und deutschen Teilnehmerinnen des bilateralen Treffens

in Ringhals, Schweden.

Präsidentin hervor. Chantal Greul, Projektleitung für die

stoffliche Produktkontrolle von Abfallgebinden bei der Fa.

Safetec, wurde gewählt und freut sich auf ihr Amt. „Ich

möchte den Verein WiN Germany in den kommenden

Jahren noch stärker auf das Thema Kompetenzen ausrichten

und versuchen, insbesondere jungen Frauen bei

uns einen Platz anzubieten. Dazu ist die Weiterführung

des WiN-Preises von besonderer Bedeutung“, betonte sie.

Seit 2011 wird jährlich von WiN Germany e.V. der mit

500 Euro dotierte WiN Germany-Preis für besondere

Leistungen von jungen Frauen in einem Fachgebiet im

nuklearen Bereich verliehen. 2018 ging der Preis, nach

Tonya Vitova (2011) und Emilia von Fritsch (2015), zum

dritten Mal an eine junge Wissenschaftlerin des KIT,

Karlsruhe. Ausgezeichnet wurde Bianca Schacherl für ihre

am INE angefertigte Masterarbeit zu Thema „Structural

investigation of Np interacted with illite by HR-XANES and

EXAFS“. Bianca Schacherl wird ihre Arbeit zudem auf dem

„Young Scientists‘ Workshop“ des 50. AMNT, 7. und 8. Mai

2019 in Berlin, präsentieren.

Zuvor im Jahr war WiN erneut international unterwegs.

Am 18./19. Oktober 2018 fand das bilaterale Treffen

mit WiN Schweden in Ringhals statt. Seit 2009 treffen sich

regelmäßig schwedische und deutsche WiNerinnen. Am

Kernkraftwerksstandort Ringhals sind vier Blöcke in Betrieb

und es ist einer der wenigen Standorte weltweit mit

sowohl Siede- und Druckwasserreaktoren. Nach der Begrüßungsrede

von Björn Linde, CEO Ringhals, gab es die

Möglichkeit, das Maschinenhaus von Block 4 zu besichtigen.

Der Abend des ersten Tages klang beim gemeinsamen

Networken aus. Fachvorträge über den Rückbau, dort

eingesetzte Verfahren, sowie die Entwicklung der Kernenergie

in Schweden und Deutschland rundeten das Programm

am letzten Tag ab. Ein besonderes Schmankerl: Im

Rahmen eines interaktiven Vortrags zweier schwedischer

Unternehmensberater wurden kleine Gruppen gebildet, in

denen die Bedeutung eines Netzwerkes, der Kerntechnik

und das Wirken in beiden Ländern erörtert wurden. Mit

vielen Ideen, neuen fachlichen Erkenntnissen und tollen

Eindrücken ging es für die deutschen WiNerinnen dann

wieder zurück nach Hause.

KTG Inside


atw Vol. 64 (2019) | Issue 2 ı February

Holen Sie sich jetzt das KTG-/AMNT-Schnupperpaket

Ein Jahr freie Mitgliedschaft in der Jungen Generation der KTG

und gebührenfreie Teilnahme am 50. Annual Meeting on Nuclear

Technology (AMNT 2019).

Empfehlen Sie das Schnupperpaket gern an andere Interessenten!

››

Antrag: „Youngster's Package“ auf www.amnt2019.com.

113

NEWS

7. – 8. Mai 2019

Estrel Convention Center Berlin, Deutschland

Herzlichen Glückwunsch!

Die KTG gratuliert ihren Mitgliedern sehr herzlich zum Geburtstag

und wünscht ihnen weiterhin alles Gute!

März 2019

88 Jahre | 1931

17. Dipl.-Ing. Hans Waldmann, Schwabach

86 Jahre | 1933

30. Dipl.-Phys. Dieter Pleuger, Kiedrich

84 Jahre | 1935

02. Dipl.-Ing. Joachim Hospe, München

83 Jahre | 1936

19. Dr. Hermann Hinsch, Hannover

81 Jahre | 1938

14. Dr. Peter Paetz, Bergisch Gladbach

80 Jahre | 1939

01. Prof. Dr. Günter Höhlein, Unterhaching

79 Jahre | 1940

01. Dipl.-Ing. Wolfgang Stumpf, Moers

03. Dipl.-Ing. Eberhard Schomer, Erlangen

18. Dipl.-Ing. Friedhelm Hülsmann, Garbsen

76 Jahre | 1943

16. Dipl.-Ing. Jochen Heinecke, Kürten

75 Jahre | 1944

02. Dr. Peter Schnur, Hannover

10. Prof. Dr. Reinhard Odoj, Hürtgenwald

11. Hamid Mehrfar, Dormitz

70 Jahre | 1949

05. Hans Gawor, Bad Honnef

65 Jahre | 1954

13. Dr. Helmut Steiner, Dillingen

60 Jahre | 1959

14. Peter Knoll, Clausthal-Zellerfeld

50 Jahre | 1969

13. Dipl.-Ing. Uta Naumann, Waldshut-

Tiengen

27. Dipl.-Ing. Christoph Mertens, Essen

40 Jahre | 1979

06. Markus Kotzanek, Eggolsheim


9. Mai 2018 ı Greaeme William Catto

Buch am Erlbach

2. Juni 2018 ı Edwin Rupp

Trier

Juni 2018 ı Dr. Norbert Rauffmann

Babenhausen

28. Juli 2018 ı Dr. Rolf Hüper

Karlsruhe

28. Juli 2018 ı

Dipl.-Phys. Eberhard Ricken

Overath

29. August 2018 ı Dr. Manfred Simon

Hirschberg

9. September 2018 ı

Dr. Gerhard Heusener

Bruchsal

15. Dezember 2018 ı

Dr. H.-Jochen Rütten

Jülich

Die KTG verliert in ihnen langjährige

aktive Mitglieder, denen sie ein

ehrendes Andenken bewahren wird.

Ihren Familien gilt unsere Anteilnahme.

Wenn Sie künftig eine

Erwähnung Ihres

Geburtstages in der

atw wünschen, teilen

Sie dies bitte der KTG-

Geschäftsstelle mit.

KTG Inside

Verantwortlich

für den Inhalt:

Die Autoren.

Lektorat:

Natalija Cobanov,

Kerntechnische

Gesellschaft e. V.

(KTG)

Robert-Koch-Platz 4

10115 Berlin

T: +49 30 498555-50

F: +49 30 498555-51

E-Mail:

natalija.cobanov@

ktg.org

www.ktg.org

Top

The IAEA and climate change:

Adaptation, monitoring and

mitigation

(iaea) Climate change is one of the

biggest environmental challenges

affecting humanity today, causing a

dangerous rise in sea levels and disturbances

to the water cycle and leading

to more frequent extreme weather

events. The IAEA helps Member States

combat climate change on a variety of

fronts: mitigating the production and

release of greenhouse gases (GHGs)

and monitoring and adapting to their

negative effects.

Atmospheric levels of GHGs have

fluctuated for billions of years,

primarily due to natural orbital, solar

and volcanic activities. Since the

middle of the eighteenth century,

anthropogenic factors have steadily

increased the concentration of CO 2 in

the Earth’s atmosphere, from approximately

278 parts per million to over

400 parts per million as of 2016,

according to the United Nations

Framework Convention on Climate

Change. This is in addition to substantial

increases in the concentration

of other potent GHGs, including

methane and nitrous oxide.

“Dealing with the effects of climate

change is not just one country’s

problem – it’s the problem of the

entire planet,” said Martin Krause,

Director at the IAEA’s Department of

Technical Cooperation. “That is why

the IAEA supports its Member States

in enhancing understanding of how

nuclear science and technology can

offset some of the consequences of

climate change.”

Adaptation

Some of the most acute effects of

climatic changes are global increases

in water scarcity and food shortages,

News


atw Vol. 64 (2019) | Issue 2 ı February

114

NEWS

| | The IAEA helps countries use nuclear science

and technology to combat climate change.

(Infographic: R. Kenn/IAEA)

the loss of biodiversity and more

frequent climate-induced natural disasters.

Unseasonably high temperatures

in winter and spring, unpredictable

weather and very short rainy

seasons contribute to water scarcity in

many regions. This, in turn, greatly affects

agricultural systems, global food

chains and, in particular, small-scale

farmers and herders.

To help communities and countries

adapt, the IAEA supports activities in

plant breeding, soil and crop management,

livestock production and insect

pest control. For example, Sudan is

using nuclear science and IAEA assistance

to help more than 35 million

people cope with climate change.

Activities include breeding new plant

varieties that are drought and heat

tolerant; setting up and optimizing

irrigation systems that save water

and fertilizer as well as improving

crop yields; and combating diseasecarrying

insects with a nuclear-based

insect pest control method called the

sterile insect technique (SIT).

Monitoring

As the international community works

towards long term solutions to the consequences

of climate change, reliable

data on how GHGs cause the changes

occurring on land, in the oceans and

throughout the atmosphere are critical.

The IAEA uses a variety of nuclear

techniques, pri marily isotopic, to identify

and monitor the risks and threats

associated with GHG emissions, and

then shares that data with Member

States to help further research and

the formulation of sustainable climate

policies. Costa Rica, for example, has

worked with the IAEA to quantify

carbon capture and monitor GHG

emissions from the dairy and agricultural

sectors. Data that Costa Rican

scientists gain from stable isotope

analysers, which help quantify carbon

emissions, facilitate efforts to move

farming towards carbon neutrality.

emissions. The IAEA provides support

to Member States to assess the development

of their energy systems and

helps them study how nuclear energy

could play a role in energy generation.

A well-informed and knowledgeable

group of professionals is essential to

develop and maintain sustainable

national energy policies.

The IAEA is conducting a coordinated

research project with Member

States on how domestic energy

policies can contribute towards

countries’ obligations under the 2015

Paris Agreement on climate change.

Through adaptation to and monitoring

of the adverse consequences of

climate change and the mitigation of

GHG emissions, the IAEA works with

its Member States to preserve and

restore the environment and protect

energy systems from climate-related

weather events and disasters.

| | www.iaea.org

World

Bernard Fontana’s statement

– EPR: the first Generation III+

nuclear reactor enters

commercial operation

(framatome) The Taishan 1 EPR reactor

in China has now entered the commercial

operation phase. Following

the first chain reaction which took

place on June 6, 2018, then successful

connection to the power grid on June

29 and the achievement of 100%

power on October 30, this new milestone

marks the final step of this major

project.

As designer of the EPR, Framatome,

now part of the EDF group, is delighted

to witness the commercial start-up of

the Taishan 1 project, a milestone that

rewards the teams’ sustained efforts

over recent years. I especially thank

our employees around the world for

their unwavering commitment through

this great adventure. I also want to

state how proud I am that we can count

among the people of Framatome, professionals

with such proven expertise

in the design and manufacture of

reactor components, I&C and nuclear

fuel systems, as well as in reactor

construction, commissioning, test and

maintenance. For six decades now, we

have been capitalizing on this experience

for the safe and reliable operation

of our customers’ nuclear reactors

around the world.

Today, Framatome is involved in the

construction and commissioning of six

EPR reactors worldwide: 2 units in

China at Taishan, 1 unit in Finland at

Olkiluoto, 1 unit in France at Flamanville,

and 2 units in the United Kingdom

at Hinkley Point. The company will be

contributing all its expertise as NSSS

specialist to serve future new build EPR

reactor projects alongside EDF.

The EPR reactor, flagship

of the French nuclear industry

The EPR is a “Generation III+” nuclear

reactor, which means that it benefits

from significant technological advances

in terms of nuclear and occupational

safety. Its design incorporates

the operational experience (OPEX)

from around one hundred nuclear

reactor projects built by Framatome

all around the world. The EPR reactor

offers economic benefits for electrical

utility customers, including reduced

generating costs, enhanced fuel use,

reduced waste volumes, increased

operating flexibility, optimized outage

times and improved operating ergonomics

leading to health benefits for

personnel.

The EPR reactor generates a net

electrical power output of 1,650 MW,

making it the largest electrical generating

unit ever built, designed for a

service life of 60 years.

| | www.framatome.com

Towards more sustainable

nuclear energy with

non-electric applications:

Opportunities and challenges

(iaea) There is considerable potential

for increasing the use of excess heat

from electricity generation by nuclear

power plants to desalinate seawater,

produce hydrogen for the heavy industry,

decarbonize the transport sector,

and supply heat to residential and

commercial uses: Nuclear cogeneration

can offer sustainable and economic

solutions for meeting the

increasing demand in heat energy

markets. However, as experts at an

IAEA meeting agreed last week, for

Mitigation

Mitigating climate change is the long

term goal, which requires approaches

and technology that will reduce GHG

| | EPR: Generation III+ nuclear reactor enters commercial operation

News


atw Vol. 64 (2019) | Issue 2 ı February

these nuclear co-generation products

to enter the commercial market on a

large scale, several challenges and

barriers have to be overcome.

Representatives from both countries

operating nuclear power plants,

as well as nuclear newcomers, technology

developers and potential customers,

discussed the pros and cons of

non-electric applications of nuclear

energy during the 16 th Dialogue Forum

of the IAEA’s International Project for

Innovative Nuclear Reactors and Fuel

Cycles (INPRO). Since 2010, these fora

have focused on different aspects of

developing sustainable nuclear energy

systems and the related complex relationships

among tech nology suppliers,

customers and other stakeholders.

Participants presented ongoing

cogeneration projects and plans or

considerations in countries embarking

on nuclear power. If such new comer

countries decide to include cogeneration

in their nuclear energy planning,

they should begin planning those

applications right from the beginning,

participants recommended.

“Nuclear cogeneration is very important,

particularly if nuclear power is

to expand much more broadly in energy

markets to meet the need for clean

and sustainable energy, while helping

to mitigate climate change through

avoidance of carbon emissions,” said

Mikhail Chudakov, IAEA Deputy

Director General and Head of the

Department of Nuclear Energy.

Traditionally, the primary focus of

nuclear power has been on electricity

generation. But as early as 1956, the

Calder Hall nuclear power plant in the

UK provided both electricity and process

heat to site facilities. There are

examples in several other countries of

district heating, industrial process heat

and seawater desalination. Despite

these examples, nuclear cogeneration

systems never really took off, for various

economic and regulatory reasons

as well as for lack of public support.

With changes in technology and the

regulatory environment in many countries,

the conditions for cogenerations

have improved substantially.

| | www.iaea.org

European Committee

supports € 2.4 billion budget

for Euratom R&D

(nucnet) The €2.4bn budget proposed

for the 2021-2025 Euratom research

and training programme is proportionate

to its objectives and should

be maintained regardless of Brexit,

the European Economic and Social

Committee said.

In an opinion adopted at its

December plenary session, the committee

said it backed the European

Commission’s proposal on the

Euratom research and training programme

for 2021-2025. The programme

is part of the 2021-2027

Horizon Europe framework programme

for research and innovation

and will run for five years, with a

possible two-year extension.

The committee said the UK’s withdrawal

from the EU should be handled

with the utmost care. “We need to be

very careful if the time comes for the

UK not to be part of the Euratom programme

any longer,” a statement said.

“We have to pay attention in particular

to research already in progress,

shared infrastructure and the social

impact on staff. Working conditions

are a priority, both on British soil and

elsewhere.”.

| | europa.eu

Reactors

Turkey grants ‘Limited Permit’

for Unit 2 at Akkuyu

nuclear station

(nucnet) The Turkish Atomic Energy

Authority has granted Akkuyu Nuclear,

the company building Turkey’s first

commercial nuclear power station, a

limited works permit for the construction

of the station’s second unit,

Rosatom has announced.

Russia’s state nuclear corporation,

which is the major consortium partner

for the project, said the TAEK issued

the permit after a review of documents

submitted by Akkuyu Nuclear.

Rosatom said the documents included

a preliminary safety analysis

report, a probabilistic safety assessment

and “other documents confirming

safety of the power unit”.

Akkuyu Nuclear must now obtain a

construction licence to start pouring

concrete for the foundation slab for

Akkuyu-2, which will mark the formal

start of construction.

In April 2018, Turkey confirmed to

the International Atomic Energy

Agency that construction of Akkuyu-1

had begun.

The IAEA said four units with a

total capacity of 4,800 MW using

Russian VVER technology are planned

for construction.

The four units at the site on the

Mediterranean coast, 500 kilometres

south of Ankara, are scheduled to be

in commercial operation by 2026.

| | www.akkunpp.com

First concrete poured

for Hinkley Point

reactor base

(nucnet) First concrete has been

poured for the first part of the reactor

base at the Hinkley Point C nuclear

power station under construction in

Somerset, England, EDF Energy said

yesterday.

The company said on social media

that workers poured concrete for

the Unit 1 reactor base, which will

provide a solid platform for the reactor

building.

The first 2,000-cubic-metre portion

was poured over 30 hours to a

thickness of 3.2 metres. Four more

pours will follow before the raft will

be complete, scheduled in 2019, EDF

Energy said.

EDF Energy is building two

Generation III EPR units at Hinkley

Point C. The station is expected to

provide 7% of Britain’s electricity

needs when fully operational.

| | www.edf.com

Company News

Westinghouse announces

initial organizational

changes

(westinghouse) Westinghouse Electric

Company, a global leader in nuclear

technology, fuels and services, today

announced the company will be

implementing the first phase of organizational

changes to enhance focus

on its customer base and to strengthen

its global services and supply chain

management capabilities.

These organizational changes

will strengthen Westinghouse’s sales

and delivery model by aligning

accountability for product and service

delivery with the regions and ensuring

optimized global sourcing. The

company expects to have all phases

of the implementation completed

by the beginning of the third quarter

2019.

“Westinghouse has been on a

journey to transform the way in

which we deliver our products and

services to our customers in the

most effective manner that will build

value for the business,” said President

and Chief Executive Officer José

Emeterio Gutiérrez. “The changes

will be a catalyst as we continue to

focus on strengthening the company’s

core business and our global supply

chain, and continuously work toward

a standard of excellence in quality,

safety, client service and innovation.”

115

NEWS

News


atw Vol. 64 (2019) | Issue 2 ı February

Operating Results October 2018

116

NEWS

Plant name Country Nominal

capacity

Type

gross

[MW]

net

[MW]

Operating

time

generator

[h]

Energy generated, gross

[MWh]

Month Year Since

commissioning

Time availability

[%]

Energy availability

[%] *) Energy utilisation

[%] *)

Month Year Month Year Month Year

OL1 Olkiluoto BWR FI 910 880 722 654 124 5 655 213 260 309 399 96.87 85.89 95.51 84.78 96.49 85.18

OL2 Olkiluoto BWR FI 910 880 745 684 577 6 263 365 250 562 546 100.00 94.51 99.98 93.74 99.88 93.31

KCB Borssele PWR NL 512 484 745 375 201 2 768 365 160 975 284 99.61 75.27 99.61 74.89 98.35 74.21

KKB 1 Beznau 7) PWR CH 380 365 745 283 604 2 024 621 126 770 708 100.00 74.47 100.00 73.89 100.19 72.93

KKB 2 Beznau 7) PWR CH 380 365 745 282 343 2 625 167 133 790 040 100.00 95.68 100.00 95.53 99.74 94.60

KKG Gösgen 7) PWR CH 1060 1010 745 788 210 7 118 799 312 313 386 100.00 92.92 99.99 95.95 99.81 49.83

KKM Mühleberg BWR CH 390 373 745 286 000 2 505 860 126 844 005 100.00 91.41 99.95 90.59 98.43 88.07

CNT-I Trillo PWR ES 1066 1003 745 791 074 6 713 847 245 738 271 100.00 87.40 100.00 87.11 98.97 85.77

Dukovany B1 PWR CZ 500 473 745 369 483 2 948 721 111 579 203 100.00 82.15 100.00 81.67 99.19 80.83

Dukovany B2 PWR CZ 500 473 745 366 765 2 883 752 107 506 290 100.00 80.80 100.00 80.26 98.46 79.05

Dukovany B3 PWR CZ 500 473 745 369 068 3 458 813 106 081 240 100.00 96.85 99.46 96.52 99.08 94.81

Dukovany B4 PWR CZ 500 473 0 0 2 649 692 105 921 433 0 73.83 0 73.49 0 72.63

Temelin B1 PWR CZ 1080 1030 745 798 219 6 287 344 112 768 638 100.00 80.29 99.94 80.00 99.02 79.69

Temelin B2 1) PWR CZ 1080 1030 708 764 694 6 177 801 107 667 747 95.03 78.74 94.65 78.55 94.86 78.37

Doel 1 2) PWR BE 454 433 0 0 1 229 715 135 444 462 0 37.01 0 36.99 0 37.11

Doel 2 2) PWR BE 454 433 0 0 1 549 672 133 801 939 0 46.61 0 46.46 0 46.70

Doel 3 PWR BE 1056 1006 745 798 954 2 380 278 253 549 500 100.00 31.35 99.98 30.59 101.17 30.74

Doel 4 2) PWR BE 1084 1033 0 0 5 638 809 260 184 650 0 71.09 0 70.95 0 70.55

Tihange 1 2) PWR BE 1009 962 291 265 903 6 799 173 297 638 048 39.04 93.54 38.70 93.29 35.32 92.53

Tihange 2 2) PWR BE 1055 1008 0 0 5 702 393 254 651 930 0 74.84 0 74.04 0 74.49

Tihange 3 2) PWR BE 1089 1038 0 0 2 332 443 271 227 273 0 29.30 0 29.26 0 29.33

Operating Results October 2018

Plant name

Type

Nominal

capacity

gross

[MW]

net

[MW]

Operating

time

generator

[h]

Energy generated, gross

[MWh]

Time availability

[%]

Energy availability

[%] *) Energy utilisation

[%] *)

Month Year Since Month Year Month Year Month Year

commissioning

KBR Brokdorf DWR 1480 1410 745 928 633 8 467 560 348 659 619 100.00 88.72 92.74 83.39 83.69 78.03

KKE Emsland 4) DWR 1406 1335 745 1 045 658 9 470 174 344 793 457 100.00 93.74 99.99 93.60 99.88 92.31

KWG Grohnde DWR 1430 1360 745 992 864 8 949 793 375 577 372 100.00 91.37 99.97 89.93 92.50 85.19

KRB C Gundremmingen SWR 1344 1288 745 998 164 8 404 075 328 983 968 100.00 88.48 100.00 88.01 99.21 85.23

KKI-2 Isar DWR 1485 1410 745 1 085 989 9 972 082 351 570 405 100.00 94.55 99.97 94.29 97.87 91.72

KKP-2 Philippsburg DWR 1468 1402 745 1 023 019 8 935 688 364 103 204 100.00 88.75 99.89 88.57 91.98 82.02

GKN-II Neckarwestheim 1,2) DWR 1400 1310 0 0 7 914 800 328 037 934 0 79.86 0 79.58 0 77.62

*)

Net-based values

(Czech and Swiss

nuclear power

plants gross-based)

1)

Refueling

2)

Inspection

3)

Repair

4)

Stretch-out-operation

5)

Stretch-in-operation

6)

Hereof traction supply

7)

Incl. steam supply

8)

New nominal

capacity since

January 2016

9)

Data for the Leibstadt

(CH) NPP will

be published in a

further issue of atw

BWR: Boiling

Water Reactor

PWR: Pressurised

Water Reactor

Source: VGB

Key enhancements include:

Creation of customer-focused business

units serving the existing nuclear

operating fleet with single points of accountability

for both sales and delivery

for existing nuclear operating plants.

Development of a new business

unit with accountability for key

growth areas related to the specific

stages of plant lifecycle solutions

including new plant delivery; plant

deconstruction, decommissioning

and remediation services; and government

services.

Establishment of an operations

delivery support function to build

Global Supply Chain into a best-inclass

organization that will support the

business units through a robust procurement

organization. This function

will also provide global engineering,

manufacturing and other technical capabilities

in order to ensure our

customers receive the full breadth of

Westinghouse’s global products, innovations

and technical capabilities.

This strengthened business unit

model is a further evolution of Westinghouse’s

operating model. Under

this model, the Chief Operating

Officer role has been restructured as

part of a broader reorganization of the

com pany. As a result, Chief Operating

Officer Mark Marano has elected to

retire.

Commenting on the transition,

Gutiérrez stated, “Mark has done an

outstanding job supporting the company

during his tenure at Westinghouse

and during our Chapter 11

process and beyond, as the Chief

Operating Officer. We thank Mark for

his leadership during this critical time

in Westinghouse’s transformation and

for his service to the industry.”

David Howell will be president of

Americas Operating Plant Services

with continued responsibilities for

commercial execution, with the added

responsibility of delivery. The change

leverages David’s strong operations

background as well as the close relationships

he has built with customers.

Bill Poirier will be president of the

EMEA Operating Plant Services

business unit on an interim basis while

the company conducts an external

search. A well-respected global industry

leader with more than 44 years

with Westinghouse, he has extensive

experience in all aspects of civil

commercial nuclear power. Bill has

supported operating plants in Europe,

News


atw Vol. 64 (2019) | Issue 2 ı February

as well the startup of several new

plants in Asia. He has been an instrumental

leader for Westinghouse in

China throughout the company’s

construction and startup of the

world’s first AP1000® nuclear power

plants.

David Durham will be president of

the newly established Plant Solutions

business unit, with accountability for

the development of key growth areas

related to the specific stages of the

commercial nuclear plant lifecycle.

These areas include his existing

responsibilities of new plant delivery

in which Westinghouse continues its

business model by providing technology,

engineering and procurement

services in a deliberative manner,

as well as government services.

David will expand his responsibilities

to include plant deconstruction,

decommissioning and remediation

services.

Pavan Pattada is a new addition

to the Westinghouse leadership team

as executive vice president, Global

Operations Services. Most recently a

senior executive with Eaton Corporation,

he will lead the Global Operations

Services organization with scope

including Global Supply Chain,

Nuclear Fuel, Global Components

Manufacturing, Global Instrumentation

and Control and Global Engineering

Services. Under Pavan’s leadership,

these areas will become global

operations and excellence hubs built

to support the business units in their

delivery of Westinghouse’s products

and services around the world while

reducing costs.

| | www.westinghousenuclear.com

Market data

(All information is supplied without

guarantee.)

Nuclear Fuel Supply

Market Data

Information in current (nominal)

U.S.-$. No inflation adjustment of

prices on a base year. Separative work

data for the formerly “secondary

market”. Uranium prices [US-$/lb

U 3 O 8 ; 1 lb = 453.53 g; 1 lb U 3 O 8 =

0.385 kg U]. Conversion prices [US-$/

kg U], Separative work [US-$/SWU

(Separative work unit)].

2014

pp

Uranium: 28.10–42.00

pp

Conversion: 7.25–11.00

pp

Separative work: 86.00–98.00

Uranium

Prize range: Spot market [USD*/lb(US) U 3O 8]

140.00

120.00

100.00

80.00

60.00

40.00

20.00

0.00

Yearly average prices in real USD, base: US prices (1982 to1984) *

Year

* Actual nominal USD prices, not real prices referring to a base year. Sources: Energy Intelligence, Nukem; Bild/Figure: atw 2019

Separative work: Spot market price range [USD*/kg UTA]

180.00

160.00

140.00

120.00

100.00

80.00

60.00

40.00

20.00

0.00

Jan. 2012

* Actual nominal USD prices, not real prices referring to a base year.

Jan. 2013

Year

Jan. 2014

Jan. 2015

2015

pp

Uranium: 35.00–39.75

pp

Conversion: 6.25–9.50

pp

Separative work: 58.00–92.00

2016

pp

Uranium: 18.75–35.25

pp

Conversion: 5.50–6.75

pp

Separative work: 47.00–62.00

2017

pp

Uranium: 19.25–26.50

pp

Conversion: 4.50–6.75

pp

Separative work: 39.00–50.00

2018

January to June 2018

pp

Uranium: 21.75–24.00

pp

Conversion: 6.00–9.50

pp

Separative work: 35.00–42.00

February 2018

pp

Uranium: 21.25–22.50

pp

Conversion: 6.25–7.25

pp

Separative work: 37.00–40.00

March 2018

pp

Uranium: 20.50–22.25

pp

Conversion: 6.50–7.50

pp

Separative work: 36.00–39.00

April 2018

pp

Uranium: 20.00–21.75

pp

Conversion: 7.50–8.50

pp

Separative work: 36.00–39.00

May 2018

pp

Uranium: 21.75–22.80

pp

Conversion: 8.00–8.75

pp

Separative work: 36.00–39.00

June 2018

pp

Uranium: 22.50–23.75

pp

Conversion: 8.50–9.50

pp

Separative work: 35.00–38.00

Jan. 2016

) 1

Jan. 2017

Jan. 2018

2015

Jan. 2019

Source: Energy Intelligence, Nukem; Bild/Figure: atw 2019

2018

Uranium prize range: Spot market [USD*/lb(US) U 3O 8]

140.00

) 1

| | Uranium spot market prices from 1980 to 2018 and from 2008 to 2018. The price range is shown.

In years with U.S. trade restrictions the unrestricted uranium spot market price is shown.

120.00

100.00

80.00

60.00

40.00

20.00

0.00

* Actual nominal USD prices, not real prices referring to a base year. Year

Sources: Energy Intelligence, Nukem; Bild/Figure: atw 2019

July 2018

pp

Uranium: 23.00–25.90

pp

Conversion: 9.00–10.50

pp

Separative work: 34.00–38.00

August 2018

pp

Uranium: 25.50–26.50

pp

Conversion: 11.00–14.00

pp

Separative work: 34.00–38.00

September 2018

pp

Uranium: 26.50–27.50

pp

Conversion: 12.00–13.00

pp

Separative work: 38.00–40.00

October 2018

pp

Uranium: 27.30–29.00

pp

Conversion: 12.00–15.00

pp

Separative work: 37.00–40.00

| | Source: Energy Intelligence

www.energyintel.com

Cross-border Price

for Hard Coal

Cross-border price for hard coal in

[€/t TCE] and orders in [t TCE] for

use in power plants (TCE: tonnes of

coal equivalent, German border):

2012: 93.02; 27,453,635

2013: 79.12, 31,637,166

2014: 72.94, 30,591,663

2015: 67.90; 28,919,230

2016: 67.07; 29,787,178

2017: 91.28, 25,739,010

2018

I. quarter: 89.88; 5,838,003

II. quarter: 88.8258; 4,341,359

| | Source: BAFA, some data provisional

www.bafa.de

Jan. 2012

Conversion: Spot conversion price range [USD*/kgU]

14.00

12.00

10.00

8.00

6.00

4.00

2.00

0.00

Jan. 2013

* Actual nominal USD prices, not real prices referring to a base year. Year

Source: Energy Intelligence, Nukem; Bild/Figure: atw 2019

| | Separative work and conversion market price ranges from 2008 to 2018. The price range is shown.

)1

In December 2009 Energy Intelligence changed the method of calculation for spot market prices. The change results in virtual price leaps.

) 1

Jan. 2012

Jan. 2013

Jan. 2014

Jan. 2014

Jan. 2015

Jan. 2015

Jan. 2016

Jan. 2016

Jan. 2017

Jan. 2017

Jan. 2018

Jan. 2018

Jan. 2019

Jan. 2019

117

NEWS

News


atw Vol. 64 (2019) | Issue 2 ı February

118

NUCLEAR TODAY

John Shepherd is a

journalist who has

covered the nuclear

industry for the past

20 years and is

currently editor-in-chief

of UK-based Energy

Storage Publishing.

Links to reference

sources:

World Energy Outlook

2018 – https://

bit.ly/2PW2Ub6

The Nuclear Power

Dilemma: Declining

Profits, Plant Closures,

and the Threat of

Rising Carbon

Emissions – https://

bit.ly/2AN1zup

World Nuclear News

report – https://

bit.ly/2D9ZmLn

Nuclear Has Every Reason to Plan

for a New Energy Horizon

John Shepherd

The global electricity sector is experiencing its most dramatic transformation since its creation more than a century

ago. That was part of the conclusion reached by the International Energy Agency (IEA) in a fascinating report recently

released by the Paris-based agency.

On the face of it, supporters of expanding the role of

nuclear energy would not have found much to cheer about

in the World Energy Outlook 2018 report – although I

should stress at the outset the report was fair and balanced.

One might conclude, however, the report offered a

gloomy outlook for nuclear. For example, the IEA forecast

that the share of generation from nuclear plants – the

second-largest source of low-carbon electricity today after

hydropower – would remain at around 10 % by 2040.

The report said global electricity generation would increase

by some 60 % (15,000 TWh) between 2017 and 2040

under the IEA’s ‘new policies scenario’. “Fossil fuels remain

the major source for electricity generation, but their share

falls from around two-thirds today to under 50 % by 2040.”

Coal and renewables will “switch their position in the

power mix”, according to the report. “The share of coal

declines from around 40 % today to a quarter in 2040 while

that of renewables grows from a quarter to just over 40 %

over the same period. The share of natural gas remains

steady at over 20 %.”

Hydropower remains the largest low-carbon source of

electricity in the new policies scenario, contributing 15 %

of total generation in 2040. Renewables altogether account

for more than 70 % of the increase in electricity generation.

Solar PV costs are projected to fall by more than 40 %

to 2040, “underpinning a nine-fold growth in solar PV

generation, mainly in China, India and the US”.

Meanwhile, some two-thirds of today’s nuclear fleet in

advanced economies is more than 30 years old. And as the

IEA report points out, decisions to extend, or shut down,

this capacity “will have significant implications for energy

security, investment and emissions”.

The IEA sees China becoming the country with the

largest generation of nuclear-based electricity as the

nuclear fleet in advanced economies ages.

However, as the IEA itself acknowledged, “the world is

gradually building a different kind of energy system, but

cracks are visible in the key pillars”. Those pillars include

affordability (think falling PV and wind costs but climbing

oil prices). On reliability, risks to oil and gas supply remain

(as recent events in Venezuela show). There is also the

question of sustainability. According to the IEA, after three

flat years, global energy-related carbon dioxide (CO 2 )

emissions rose by 1.6 % in 2017 “and the early data suggest

continued growth in 2018”.

I would argue it is these ‘key pillars’ that still offer

the best chance for a new generation of nuclear power

generating facilities through to 2040 and beyond.

Some of those nations that have not had the ‘luxury’ of

abundant supplies of clean electricity to drive economic

growth surely agree. Take for example India. As World

Nuclear News has reported, India currently expects to bring

21 new nuclear power reactors with a combined generating

capacity of 15,700 MWe into operation by 2031.

In addition, the nuclear industry has every reason to

look beyond the horizon of the next 20 years and think

about how technological developments can play in role in

advancing a new generation of nuclear.

New initiatives that hold promise include a proposed

US pilot programme to produce high-assay low-enriched

uranium (HALEU) in hopes of accelerating the next

generation of nuclear reactors.

The US Department of Energy (DOE) issued a notice of

intent in January 2019 to invest in the pilot project.

According to the president and CEO of the Nuclear Energy

Institute, Maria Korsnick, the move “demonstrates

continued confidence in the success of the next generation

of advanced nuclear reactors and for new fuel options for

the existing fleet”.

In terms of sustainability, nuclear still has everything

going for it. The world’s supply of uranium is more than

adequate to meet projected requirements for the foreseeable

future, regardless of the role that nuclear energy

ultimately plays in meeting future electricity demand and

global climate objectives, according to the main findings of

the latest edition of Uranium 2018: Resources, Production

and Demand, also known as the ‘Red Book’.

However, the Red Book, which is jointly prepared every

two years by the Nuclear Energy Agency and the International

Atomic Energy Agency, said significant investment

and technical expertise would be required to ensure these

uranium resources can be brought into production in a

timely manner, including from mines currently under care

and maintenance.

The world’s identified uranium resources are reported

to be 6,142,200 tonnes of uranium metal (tU), which can

be recovered at a cost of $ 130 per kilogramme or less.

“These are recoverable, reasonably assured and inferred

resources and this represents an increase of 7.4 % on the

total reported in 2016,” the Red Book said. However, the

publication cautioned that while some of these increases

are due to new discoveries, the majority results from

re-evaluations of previously identified uranium resources

– and “strong market conditions will be fundamental to

attracting the required investment to the industry”.

And beyond the facts that support the case for nuclear,

even the hardest hearts previously set against the technology

are melting. Towards the end of 2018, the Union of

Concerned Scientists (UCS) overturned its longstanding

opposition by issuing a report that urged federal and state

policies in the US to help preserve safely operating nuclear

plants that were at risk of premature closure.

The UCS has seen the light – and said its call was

necessary to ensure nuclear’s low-carbon energy was not

replaced by fossil fuels.

The shift in position of the UCS is every bit as important

as when environmentalist James Lovelock upset the Green

movement by coming out in favour of nuclear energy.

Nuclear can clearly still win over hearts and minds on its

merits and record. It deserves investment to fulfil its

essential role as part of a clean energy solution for the

future.

Author

John Shepherd

Nuclear Today

Nuclear Has Every Reason to Plan for a New Energy Horizon ı John Shepherd


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Decommissioning Experience & Waste Management Solutions

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Unsere Jahrestagung – das Original seit 50 Jahren.

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