Poland advances multi‑billion zloty energy storage with pumped‑hydro plant and city‑wide thermal accumulator

Poland is investing several billion zlotys in large‑scale energy storage. Near Nowy Sącz, the Rożnów II pumped‑hydro plant will be built in the Łososina Dolna gmina, linking to an existing hydro power station. The project, costing about 6.8‑7 billion PLN, will have a capacity of roughly 767 MW and store around 3.1 GWh of electricity. Planned operation runs from 2028 to 2033, and the facility will also provide flood protection for the Rożnów reservoir. The initiative was backed by Energy Minister Miłosz Motyka and TAURON Polska Energia.

In Warsaw, the Elektrociepłownia Żerań is constructing a 65‑metre‑tall heat accumulator – described as a giant thermal "thermos" – slated for completion in September 2027. The tank will hold 61,000 m³ of water (equivalent to 24 Olympic‑size pools), allowing storage of nearly 10 TJ of heat and delivering up to 230 MWt to the city's heating network. It is designed to heat about 75,000 apartments during winter and will be filled and tested with water over the coming months.