Hydroelectric energy - Energie EDF

Series: | The future of our energy
Hydroelectric
energy

“How to reconcile power
generation with environmental
protection?“
“Is EDF
competitive?“
“25% of the world’s
population uses almost
two thirds of the world’s
energy resources.“
PERFORMANCE
SAFETY
ENERGY EXPERTISE
A key player in the landscape of energy
challenges, EDF generates ample quantities
of energy in varied and environmentallyfriendly
forms, thus providing the wider
public with access to electricity.
“Energy demand could
increase by 60% by the
year 2030.“

EDF,
EUROPEAN
LEADER IN POWER
GENERATION
The EDF group has a stake in the main
leading European energy markets:
the United Kingdom with EDF Energy,
Italy with Edison, and France where EDF
is leader in its market. With its mix of
nuclear, hydroelectric, fossil-fi red and
other renewable energies, EDF operates
a highly effi cient, diversifi ed and
comprehensive power generation fl eet.
POWER GENERATED BY EDF
IN MAINLAND FRANCE, 2010*
407.9 TWh
86.7%
Nuclear
45.4 TWh
9.7%
Hydroelectric**
16.9 TWh
3.6%
Fossil-fi red
* These fi gures are rounded off to one decimal point as compared with
exact values.
** Including power generated by pumped-storage plants.
INSTALLED CAPACITY
in France as at 31 December 2010.
NATIONAL POWER OUTPUT*
were generated by EDF in France in 2010.
of the electricity generated
by EDF does not emit greenhouse
gases.
FRENCH FLEET
19 nuclear
power plants
439
hydroelectric
plants
UNITS OF MEASUREMENT
• Mechanical and electrical power is measured
in Watts (W).
• The megawatt/hour (MWh) is the amount of
power generated by a 1-megawatt (MW) generation
facility within a one-hour period.
• 1 MW = 1 000 kilowatts (kW) = 1 million watts.
• 1 terawatt/hour (TWh) is equal to
1 billion kWh.
23 fossil-fi red
plants
and
13 gas
turbines

Turbine building
at the Pragnères
power plant.

Cover:
Sainte-Croix-de-Verdon
dam (Alpes-de-Haute-
Provence).
04
Water: the
world’s main
form of
renewable
energy
A clean and
fl exible form of
energy, water
ranks fi rst among
the world’s
renewable
energies.
06
The incredible
fl exibility of
water
Hydro power: an
essential
component of
France’s energy
landscape.
08
From water to
electricity:
how does
it work
How a hydraulic
plant works.
10
Hydro power:
energy of the
future
Hydro power and
tomorrow’s
economic and
environmental
challenges
Creation of series: Spécifi que
Production and design:
Translation: Concept & Langage – Photo credits:
Onoky/Photononstop, Getty Images/DR,
EDF media library/Laurent Baratier, Gilles de Fayet,
Claude Pauquet, Thierry Renavand
Printers: JPA - REF.ENE965-2011
Printed on 50% recycled, 50% FSC paper.
Hydro power:
the energy of choice
By 2020, 20% of European electricity demand will
have to be met by resorting to renewable energies,
if greenhouse gas emissions are to be reduced.
In France, 10% of the electricity generated by EDF is
already being sourced from hydro power facilities.
The world’s main renewable energy form,
hydroelectric energy is a sustainable, fl exible and
competitive source of electricity. As it does not emit
carbon dioxide, it is also of great benefi t
to the environment. Furthermore, it provides an
inexpensive solution to sudden fl uctuations in
electricity demand. Being a public commodity, it is
essential that suffi cient supplies of water be made
available to cater for all needs: electricity, drinking
water, farming, industry and tourism. It goes
without saying that every effort is made to
guarantee absolute safety.
www.edf.com

Hydroelectric energy
WATER: THE WORLD’S
MAIN FORM OF
RENEWABLE ENERGY
Hydro power is an essential source of electrical energy, standing head to
head with nuclear energy on a global scale. It ranks first among all renewable
energy forms.
This environmentally-sound energy form does not contribute to the increase in
greenhouse gases or to air pollution, as it does not emit carbon dioxide or any
polluting gases.
Hydroelectric power has its own place within the natural water cycle (rainfall,
snow melt, mountain streams and rivers): water is kept in dams and used to
drive turbines and generate electrical current.
It is not so much the water head as the amount of available water contained
in the dam that determines a hydro plant’s capacity. Indeed, the world’s four
leading hydropower producers are flat countries with large catchment areas:
United States, Russia, Canada and Brazil.
France’s natural landscape provides the ideal conditions for hydroelectric
power generation: regular rainfall, contrasting terrain, long waterways and
a dense hydrographical network.
04
GREENHOUSE
EFFECT
This natural
phenomenon leads
to the warming of
the atmosphere and
surface of a planet
that is exposed to
solar rays.

Renewable energies
These are very long-term, inexhaustible
sources of primary energy, as they are
directly or indirectly derived from solar
energy, the earth’s energy or gravity.
Renewable energies include solar
energy, wind energy, hydro energy
(dams), the biomass (organic matter that
releases energy, such as burning wood),
geothermal energy that uses heat from
the depths of the earth, and tidal
energy. These energy forms do not
become depleted and most of them are
non-polluting.
GLOBAL ELECTRICAL POWER OUTPUT IN 2009
Source: Observ’ER 2010
67.2%
Fossil fuels (coal,
petroleum, gas)
16.1%
Hydro
13.5%
Nuclear
3.2%
Others renewable
energies
hydro power producer
EDF is the European Union’s leading hydro
power producer, with more than 20,000 MW of
installed capacity spread across nearly 450 hydro
power sites, ranging from about 10 kW to
several hundreds of MW. 70% of France’s
hydroelectric energy potential, estimated at
98 TWh/year, is currently being used. Hydro
energy plays an instrumental role in France’s
energy independence, saving the country as
many as 13 million tons of oil every year.
DID YOU KNOW?
CLEAN AND ECONOMICAL
While hydro power is dependent upon the
vagaries of climate, it is nevertheless the only
fi nancially viable source of renewable energy.
7.5 BILLION CUBIC METRES
The total volume of water stored in all EDF dams.
05

Hydroelectric energy
THE INCREDIBLE
FLEXIBILITY OF WATER
Adjusting load on the French power grid
With water reserves amounting to 7.5 billion cubic meters, and 20 GW of installed
capacity, dams and hydroelectric plants are able to constantly adjust the quantity
of power generated to the variations in demand for electrical current (in very
cold weather or during peak periods, or as a result of incidents occurring on the
grid or at other plants), thereby adding to the power generated by nuclear and
fossil-fi red facilities. The hundred leading hydro plants are controlled by four
hydroelectric control centres located in Lyon, Toulouse, Sainte-Tulle and Kembs.
Energy on tap
While energy cannot be stored on a large scale, water can nevertheless be
captured in large reservoirs by using dam walls or dikes to store potential energy.
The release of this water unleashes this energy, the magnitude of which increases
or decreases in proportion to water head and fl ow rate. The channelled water
drives turbines which generate electricity immediately. A hydroelectric plant can
reach its maximum capacity within a few minutes, as opposed to about 10 hours
for a conventional fossil-fi red plant and about forty hours for a nuclear reactor.
Its fl exibility and country-wide water reserves make hydro energy the ideal means
for adjusting electrical power during periods of peak demand.
06
20 GW OF
INSTALLED
CAPACITY
45 billion kWh
generated each
year.
439 plants ranging
from less than a
hundred kW to
1,800 MW.
640 dams, 150 with
a head of more
than 20 metres.

Operating around the clock and 365 days a year,
the operating centres cater to the needs of the
national grid and remotely control the country’s
hydro generation facilities, promptly responding to
peaks in demand.
SPREAD OF INSTALLED CAPACITY
IN MAINLAND FRANCE (EDF FLEET).
Central France
South-Western
France
Eastern
France
Alps
Mediterranean
1,800 MW within the space
of 2 minutes
Commissioned in 1985, the
Grand’Maison power plant in the
Isère, region of France, is the
most powerful hydroelectric facility
in France. Within the space of
two minutes, it is able to generate
1,800 MW of electrical power,
tantamount to the power generated
by two nuclear reactors.
Grand’Maison is a pumped-storage
facility that uses two reservoirs at
two different heights. During periods
of high demand, the water in the
upper reservoir is pumped down to
the lower reservoir. When the
demand for electrical power drops,
the water is pumped back to the
upper reservoir.
07

Hydroelectric energy
FROM WATER
TO ELECTRICITY:
HOW DOES IT WORK
From source to power plant
From time immemorial, the force of water has always fascinated man,
while its secrets have been known since ancient times: harnessing of
water, aqueducts, water head, wheels and mills. Mediaeval industry grew
through the harnessing of this driving force. The invention of the turbine,
followed by that of the generator in the 19 th century made it possible to
generate electricity from hydro energy.
A precursor in the use of energies harnessed from the sea, EDF has been
operating the tidal plant at la Rance (Ille-et-Vilaine) for more than
40 years. In July 2008, EDF decided to build a pilot marine turbine farm at
Paimpol-Bréhat (Côtes-d’Armor) in order to harness energy from sea
currents to generate electricity.
08

How
a hydro plant
works
The principle is simple and relies on the force of gravity:
potential energy from water contained in dams is
converted into mechanical energy by means of a turbine,
which is in turn converted into electrical energy using a
generator.
The dam is used to store up large quantities of water by
forming a lake (1). When the sluice gates are opened, the
water fl ows into a penstock or channel (2) which directs it
towards the power plant. The water causes the turbine to
rotate (3). The turbine drives the generator (4), which
generates electrical current. This current is rectifi ed by a
transformer (5) before being transmitted along highvoltage
power lines. Outside the power plant, the water
returns to the river via the tail-race (6).
HOW A HYDRO PLANT WORKS
Storage reservoir
1
Tunnel
Dam
2
Penstock
3
Turbine
4
Generator
5
Transformer
6
Different plants for different
landscapes
Hydro plants come in a
variety of forms, depending
on the layout of the
waterway, the terrain or the
water head:
– Mountain sites with a steep
gradient, such as the Portillon
plant in the Pyrenees (1,420 m
head in a penstock), but with
a low fl ow rate;
– Medium-head plants with a
higher fl ow rate;
– Run-of-river plants, with a
slight gradient (10-15 m) but a
very high fl ow rate, as found
in large rivers (Rhine, Rhône,
Isère, Durance, etc.);
– Pumped-storage plants,
pumping water downhill
during peak periods and
pumping water uphill during
quiet periods;
–Tidal plants, such as la Rance
in Ille-et-Vilaine, driven by the
tides.
Depending on the type of
dam (arch dam, weight,
abutments, rock fi ll or earth
dam, moveable dam, high,
medium or low-head dam),
three types of turbine are
essentially used: Pelton,
Francis and Kaplan
respectively.
DID YOU KNOW?
AVAILABLE CAPACITY
Available capacity (kW) is a
combination of two factors:
water head (m) and derived
fl o w ( m 3 /s).
09

Hydroelectric energy
HYDRO POWER:
ENERGY
OF THE FUTURE
Given the challenges arising over the forthcoming decades in the form of a
two-fold increase in global energy demand, compounded by the greenhouse
effect, renewable energies, including hydro power, will be occupying centre stage.
At the outset of this 21 st century, one person in two does not have access to
electricity. At the same time, the growth of developing countries has given rise to
huge energy demand. It will no longer be possible to meet this demand using fossil
fuels as was the case in the previous century, given their harmful effects on the
atmosphere and climate, and diminishing global supplies (oil, gas).
In addition to nuclear energy and research, improved thermal generation capacity
relies on the use of renewable energies. Among these, hydro energy is the least
expensive to generate and stands head and shoulders above the others. Indeed,
many countries only tap about 10% of their hydro energy potential.
Internationally speaking, the EDF Group has committed itself to numerous
development programmes, contributing its experience in hydroelectric engineering.
In Laos, for instance, the 1,070 MW Nam Theun 2 hydro plant, wich was
commissioned in 2010, is now helping the country to expand its energy resources.
10
HYDRO ENERGY POTENTIAL
In France, 70 TWh out
of a technically achievable
98 TWh are generated each
year. This output could be
increased:
1) by upgrading the 10 to
50-MW plants of the existing
fl eet (23 TWh) or by building
new dams like those of
Romanche-Gavet in the Isère
or on the Rizzanese River
in Corsica currently under
construction;
2) by developing small
hydroelectric facilities,
i.e. units of 0.1 to 10 MW
(4 TWh), or by refurbishing
old mills (pico-hydro power,
ranging from 10 to 100 kW)
already in place (1 TWh).

DID YOU KNOW?
In order to generate electricity, hydroelectric plants
release water from their dams. As a result, water fl ow
and current increase downstream of the structure,
potentially posing a risk to people in the vicinity or in
the riverbed.
Even so, these water releases are required in order to
rotate turbines during periods of peak demand, to
satisfy the needs of farmers and industrialists, to
maintain a minimum fl ow that is compatible with
downstream ecosystems, and to reduce high water
levels. In order to mitigate this risk, information
campaigns are regularly organized and 10 000 yellow
signboards with the warning “Attention danger!” are
placed along the banks of rivers, lakes and canals.
CLOSELY MONITORED
STRUCTURES
Dams are affected by water mass and pressure, as well
as by changes in temperature. The safety of hydroelectric
plants therefore requires that each site and its facilities
be kept under constant scrutiny. Dams are therefore
constantly inspected and monitored. On the occasion of
regulatory ten-year outages, dams may be drained in
order to check the condition of sections that are normally
submerged. Robots are sometimes used to avoid having
to drain the dams.
EDF AND THE
PRESERVATION OF FLORA
AND FAUNA
EDF builds fi sh lifts and
ladders to help migrating
fi sh, such as salmon, over
the dams.
“What makes EDF
such a key player where
water is concerned?”
“EDF has always had a close
relationship with water. In order to
generate electricity, the company
harnesses water directly as a driving
force for its hydroelectric plants, and
indirectly as a heat sink on its
conventional and nuclear plants.
However, water is also needed for
other, equally important purposes
such as public consumption,
agriculture, industry and tourism.”
“How is the just distribution
of water guaranteed?”
“One has to start by forecasting
future water reserves on the basis of
hydro-climatic factors such as snowfall
or rainfall in catchment areas. It is the
duty of the public authorities, in
conjunction with various other players
including local authorities and water
agencies, to ensure that water is
distribued fairly.”
11

GEOGRAPHICAL LOCATION OF
EDF HYDRO PLANTS IN FRANCE
Saint-Martin
Saint-Barthélémy
Guadeloupe
SURINAM
Bananier
Petit Saut
French Guiana
Les Saintes
Marie-Galante
Saint-Pierre-et-Miquelon Martinique
Atlantic
Ocean
BRAZIL
EDF
Cap Ampère – 1, place Pleyel
93282 Saint-Denis cedex
Quimper
Réunion
Takamaka
Bras de
la Plaine
Head offi ce: 22-30, avenue de Wagram – 75008 Paris
Limited company with a capital of 924 433 331 euros
RCS Paris 552 081 317
www.edf.com
Ref.:ENE965-2011
La Rance
Rennes
Rivière
de l’est
Langevin
Cherbourg
Nantes
Tours
Orléans
Bourges
Amiens
Paris
Lille
Revin
Reims
Le Crescent
Chaumeçon
Gambsheim
Strasbourg
Gerstheim
Vieux Pré Rhinau
Marckolsheim
Vogelgrün
Mulhouse
Fessenheim
Ottmarsheim
Kembs
Besançon
Reservoir hydro plant
50 to 100 MW
100 to 250 MW
+ 250 MW
Run-of-river plant
with pond
50 to 100 MW
100 to 250 MW
+ 250 MW
Eguzon
Vouglans
Coiselet
Saut-Mortier
Run-of-river plant
Limoges
Peyrat-le-Château
Vassivière
Villerest
Clermont-Ferrand
Cize-Bolozon
Passy
Allement Les Bois
Lyon Cusset
Albertville
without pond
50 to 100 MW
100 to 250 MW
L’Aigle
Le Chastang
Bort-les-Orgues
Grenoble
+ 250 MW
Argentat
Avrieux
Grandval
Villarodin
Bordeaux Tuilières
Sarrans Montpezat Cordeac /
Laval- St-Étienne-
Cantalès Brommat
Le Sautet
de-Cère Couesque
Montezic
Pied-de-Borne
Serre-Ponçon
Lardit Castelnau Sisteron Curbans
Golinhac
Golfech
Salignac St-Martin-Vésubie
Le Pouget
Le Bazacle
Oraison
Mallemort
Castillon St-Dalmas
Albi
Nîmes Ste-Tulle
Montahut
Bancairon
Salon
Manosque
Montpellier
Toulouse
St-Chamas Jouques Ste-Croix Nice
St-Estève
Nentilla
Marseille
Pragnères
Aston Escouloubre
Auzat
Portillon
Orlu
Tidal plant
100 to 250 MW
Pump house
+ 250 MW
Sites in
Corsica and
in the French
overseas
departments
and territories
Laparan
L’Hospitalet
Albertville
La Bâthie
Pont de la
Vanna
Castirla
Corscia
Sovenzia
Tolla
Ocana
Lugo di Nazza
with a 50 MW
capacity
Le Cheylas
Grenoble
Randens
La Coche
Les Brévières/
Tignes
Rizzanese
St-Georges
de Commiers
Grand’Maison
St-Guillerme
Monteynard
Pont-Escoffier
Hermillon
La Saussaz
Super-
Bissorte
Orelle
Bissorte
Pralognan
Aussois
Generation The EDF Group is ISO 14001 certifi ed March 2011