Hydroelectricity is the second source of electricity generation after nuclear power and the first source of renewable electricity in France. This is an important sector for the electricity system for many reasons, particularly in terms of grid security and balancing.
EDF’s hydropower fleet in mainland France includes about 500 plants, including the plants belonging to French subsidiaries and cross-border companies (Franco-Germanand Franco-Swiss power plants). There were 427 plants within the scope of EDF SA at the end of 2020, with an average age of 75 years(1) :
Hydropower plants | 31/12/2020 | 31/12/2019 |
|---|---|---|
Total Maximum Capacity (in GW) | Total Maximum Capacity (in GW) 31/12/2020 20.1 | Total Maximum Capacity (in GW) 31/12/2019 20.1 |
Total Output including Pumping* (in TWh) | Total Output including Pumping* (in TWh) 31/12/2020 4.7 | Total Output including Pumping* (in TWh) 31/12/2019 39.7 |
*Corresponds to the sum of the exact values rounded to one decimal place.
Within mainland France, hydropower plants are mainly located in mountainous areas in the Pyrenees, the Alps, the Massif Central and the Jura, as well as on the Rhine.
In all, they represent an installed capacity of approximately 20.1GW (excluding French overseas departments and Corsica), or 23.1% of EDF fleet’s installed capacity, for an annual productible energy of more than 40TWh.
The various hydropower facilities are designed to optimise the use of water resources in the valleys where they are situated, as part of multi-purpose water management (detailed in section 1.4.1.3.1.4 “Hydropower generation issues”).
Given the size and variety of its fleet, EDF has facilities able to respond to all types of desired uses, from base to peak generation which also offer levers for optimisation due to their flexibility:
Facility category | Turbine capacity | Average gravity capacity over 50 years (1) |
|---|---|---|
| Run-of-river | Run-of-river Turbine capacity 3.6GW | Run-of-river Average gravity capacity over 50 years (1) 16.7 TWh |
| Lake-supplied | Lake-supplied Turbine capacity 8.1GW | Lake-supplied Average gravity capacity over 50 years (1) 14.5TWh |
| Pondage | Pondage Turbine capacity 3.1GW | Pondage Average gravity capacity over 50 years (1) 8.1TWh |
| Pumped-storage (2) | Pumped-storage (2)Turbine capacity 5.0GW | Pumped-storage (2)Average gravity capacity over 50 years (1) 1.5TWh |
| Tidal | Tidal Turbine capacity 240MW | Tidal Average gravity capacity over 50 years (1) 0.5TWh |
(1) The average production over 50 years has been re-evaluated on the basis of observed climate change.
(2) Only gravity capacity is counted in the STEPs; pumped energy is not taken into account..
EDF SA’s hydropower electricity generation in mainland France before deduction of power required to operate pumped-storage plants was 44.71TWh, amounting to 11.5% of EDF’s total electricity production.
In 2020, EDF spent nearly € 441 million in mainland France for the development and maintenance of its hydropower generation fleet to ensure optimum and safe operation.
In order to take advantage of the flexibility of its hydropower generation facilities, for some years now EDF has been initiating ambitious programmes involving automation, remote control of hydropower plants and centralised management for each valley. Currently, the largest plants in EDF’s hydropower fleet, representing over 15.6GW (around 77% of its installed hydropower capacity) are remote-controlled from four control centres able to make adjustments to the plants’ operating programmes at any time in order to respond to the needs of the electrical system and to economic opportunities arising on the electricity market.
To improve the reliability of its largest power plants, EDF monitors physical parameters (including temperature and vibration) of machinery, from five regional operations centres. This enables any discrepancy to be speedily detected; incidents can be avoided thanks to greater familiarity with the status and operational behaviour of the equipment.
Hydropower generation may witness substantial variations from one year to the next, depending on climatic fluctuations in water resources. 2020 saw a slight surplus in hydropower generation and good production performance due to all entities being used to mitigate the impact of the health crisis on the operation and maintenance of the generation fleet, against the backdrop of ongoing transformation procedures.
The 2020 generation indicators show a highly satisfactory level of performance with a low rate of internal loss(2) of 3.8% (4.0% in 2019). The overall availability of the hydropower fleet, i.e. the percentage of time over the year during which the power plants are available at full capacity, was 99.4% compared with 99.3% in 2019.
The loss rate was 3.3% in 2020 (compared to 4.0% in 2019).
Anticipating needs relating to the expansion of variable renewable energy (solar and wind power), the emphasis is on increasing the flexibility of hydroelectric production resources and adaptation of power plant remote operation to capture the opportunities opened up by the development of European intraday power trading.
In 2020, EDF’s hydropower generation fleet experienced exceptional weather damage. The Nice hinterland was severely hit by storm Alex, with a catastrophic impact on the local population. EDF’s hydropower facilities suffered from flash flooding of the Vésubie and Roya waterways, a flood with an estimated return period of 100 years. EDF ensured its personnel was kept safe and constantly checked that its installations also remained safe to ensure local residents were protected.
A large number of installations and equipment were seriously damaged along these two waterways.
(1) Arithmetic mean.
(2) Internal loss is the energy from flows that do not pass through turbines which were not stored. The rate of internal loss is obtained by dividing the internal loss by the generation performed during the year, and then adding the total loss.
