atw 2019-02

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2019
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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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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

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Ihr Weg durch Genehmigungs- und Aufsichtsverfahren RA Dr. Christian Raetzke 02.04.2019
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Atomrecht – Navigation im internationalen nuklearen Vertragsrecht Akos Frank LL. M. 03.04.2019 Berlin
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Export kerntechnischer Produkte und Dienstleistungen –
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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 2019 – 2019 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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FEATURE | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 72
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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FEATURE | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 76
| | 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)
SERIAL | MAJOR TRENDS IN ENERGY POLICY AND NUCLEAR POWER 79
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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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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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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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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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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),
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[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.
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[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
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[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.
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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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atw Vol. 64 (2019) | Issue 2 ı February
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
Medien Partner
Unsere Jahrestagung – das Original seit 50 Jahren.