The Polish Energy Group (PGE) has received a concession for the storage of energy in pumped storage power plants. Until now, power plants have benefited from a concession for energy generation, due to the lack of a definition of energy storage activities in Polish law.

Pumped storage power plants are in practice energy storage facilities. The building of such a power plant is located between two water reservoirs. At times of low electricity demand, water is pumped from the lower reservoir to the upper one. During peak hours, the process is reversed. PGE Energia Odnawialna has four such power plants: Żarnowiec, Solina, Porąbka-Żar and Dychów.

In accordance with their generation concession, the power plants paid full transmission and distribution charges. This also applied to energy that was supplied to consumers after storage. A transmission and distribution charge were again levied on it by PGE Energia Odnawialna.

Under the new type of concession, electricity storages are billed only for the energy consumed during the storage process. They pay fees based on the amount of energy injected into and withdrawn from the grid. In practice, this means that the more efficient the storage facility is, the lower the charges it incurs. For PGE’s pumped storage plants, these reductions reach over 70 %.

The main advantage of pumped storage power plants is the equalisation of the power balance in the electricity system. These types of power plants are able to respond to sudden changes within 2-3 minutes.

They are not sources with fixed availability, i.e. their production is completely dependent on changing weather conditions. In addition, their peak generation does not always coincide with hours of maximum demand. Storage facilities can deliver pre-stored ‘green energy’ at hours when it is most needed by consumers.

Arkadiusz Słomczyński