Pumped storage will become increasingly important in the context of energy transition, even if it is not cost-effective today. Increasingly, these facilities will be required to store excess electricity from intermittent renewables (solar, wind).
There are many solutions for short-term storage (from a few hours to a few weeks): local storage in batteries, or centralised storage using surplus electricity, either to produce hydrogen that will be injected into the natural gas grid or to pump water from our alpine storage lakes (pumped storage).
Raising some dams will increase their storage capacity, allowing them to play a greater role in regulating our electrical system. Above all, it would contribute to the seasonal storage of electricity at a rate of 2 to 3 TWh, reducing our winter imports and substantially increasing our energy independence.
The storage of heat is commonly practised on a daily basis in “boilers”. However, long-term heat storage for the duration of a season (heat produced in summer and used in winter) is still too expensive in Switzerland.
It is possible, through incentives, to modulate the consumption of electricity in order to better adapt it to the production capacity. This strategy would reduce the need for storage and even avoid the need to store excess electricity from solar and wind power.