September 15, 2025: Renewables group Zelestra and Swiss energy firm BKW have agreed a deal to build a 2 GWh BESS in northern Italy.

The companies said on September 10 construction is due to start in 2027 with full operation anticipated in 2028, although the battery chemistry and financial details were not disclosed.

The agreement involves a long-term financial tolling arrangement, said to be the first of its kind in Italy, under which Zelestra will make part of the plant’s generation capacity available to BKW to manage and optimize flexibility in the market.

Zelestra is backed by EQT, a leading global fund with more than €273 billion ($320 billion) in total assets under management, and said Italy’s north has high demand for electricity from industrial customers — with increasing renewables capacity coming on to the grid alongside an expected phase out of fossil-fuel powered plants.

The BESS project expands on an existing clean energy partnership between BKW and Zelestra. Last December, the partners closed a 10-year power purchase agreement supporting the construction of two solar projects in the country totalling 16 MWdc (MW on a direct-current, nameplate-capacity).

Martina Nicodemo, BKW’s commercial lead for renewables and BESS in Italy said the country is one of the most attractive battery storage markets in Europe.

BKW head of trading and origination Bianca Sarbu said: “Beyond the technical achievement, this project underlines both our strong presence in the Italian market and our ambition to keep growing.”

Eliano Russo, Zelestra’s country manager in Italy, said: “As a multi-technology developer, we are pleased to expand our global footprint for battery storage projects, with multiple contracts already executed elsewhere in Europe, Latin America and India.”

Russo said Italy is a key growth market for the company. Zelestra has a mature project portfolio of around 1,400 MW of solar and BESS projects in Italy and intends to take part in both Macse (the storage capacity acquisition mechanism) and capacity market auctions for BESS projects and Italy’s ‘FER X’ green energy auction for solar projects this year.

Batteries International reported last month that Zelestra had secured the $282 million financial close to develop a 1 GWh battery and solar ESS plant in Chile. That facility will use China-based Sungrow’s PowerTitan 2.0 liquid-cooled silicon carbide power conversion system units with LFP-based battery tech.