As the ecological transition moves forward, there has been a boom in energy storage in general, and electrochemical battery cells in particular. The goal of developing this technology is to:
- Contribute to security of supply (via capacity mechanisms and primary frequency control);
- Increase the rate of self-consumption by storing surplus energy for later use;
- Make supply more reliable by optimising the management of local constraints, thus reducing the risk of micro outages…
Electricity storage systems make it possible to withdraw a specific quantity of energy from the network and store it before later releasing it back into the grid at the connection point. Storage solutions can be:
- Mechanical: STEP pumped storage stations, Compressed Air Energy Storage (CAES), electrochemical (batteries, etc.);
- Chemical (fuel cell, etc.);
Within the scope of RTE’s businesses, the storage capacity in use today is associated with hydropower, whereas for ENEDIS, most is battery-based.
In 2020, total storage capacity reached 4,850 MW of which 4,810 MW was hydropower-based and 40 MW battery-based. These levels were unchanged from the previous year.