The Polish capacity market auction for 2029 which awarded more than 8 GW of capacity contracts was a success for battery energy storage projects. While final results are yet to be released in January, industry insiders assess that the procurement exercise could have catalyzed around 4.2 GW of battery energy storage system (BESS) capacity pre-derating.

A derating factor is a multiplier applied to the actual generation capacity of a unit to determine the maximum size of contract it can secure in the capacity market auction. It is based on the expected availability of the dispatchable capacity in hours when demand is highest. For the 2029 CM procurement, it stood at 61.3%.

This would mean that around 2.5 GW of BESS has secured contracts although this figure could be even higher considering the possibility that some of the projects could have had even bigger nominal power output if they were batteries with shorter storage duration than four hours.