Italian energy company Enel will integrate a 4 MW/8 MWh lithium-ion BESS with the 43.4 MW Dossi pumped storage hydroelectric power plant, in Bergamo, Italy.

Enel’s BESS4Hydro project, backed by the European Union’s Innovation Fund, aims to improve the efficiency and flexibility of hydroelectric energy storage. The battery will act as a secondary reservoir, storing electricity and injecting it into the grid via the same connection point as the pumped storage plant, ensuring uninterrupted supply.

The Dossi power station, built in 1923 in the municipality of Valbondione, includes a complex, high-altitude hydraulic system. The Valmorta dam was completed in the same year, followed by the Barbellino dam, in 1931.

“The main objective is to equate the grid balancing capabilities of pumped storage plants with those of conventional thermal power plants and to improve adaptability to fluctuations in demand and market dynamics,” Enel said. “The innovative design improves the provision of [grid] ancillary services, extends service life, and optimizes efficiency by reducing wear on turbine components. In addition, the integration of BESS allows autonomous operation during periods of inactivity of pumped storage plants, ensuring continuous energy supply and grid stability.”