Bison Energy acquires 1.2 GWh BESS in Italy, pioneers floor pricing in Japan

Tokyo-based developer Bison Energy Group has acquired two early-stage battery energy storage projects in Italy totalling 300 MW/1,200 MWh.

The projects were puchased from a joint venture between ATLAS RE, a renewable energy developer, and Heron Advisory Srl, a firm specializing in renewable energy finance. Financial terms of the deal were not disclosed.

One of the projects, ATLAS STORAGE 11, located in Puglia has a power output of 225 MW and storage capacity of 900 MWh. The other project, ATLAS STORAGE 15, is situated in Sardinia and will deliver 75 MW of power and 300 MWh of storage capacity.

Both projects are expected to reach ready-to-build stage by the third quarter of 2026. “These additions mark another step in strengthening our integrated approach to driving the energy transition – as both a developer and investor,” Bison Energy said.

The move marks the second gigawatt-hour-scale acqusition in the Italian market within days. Just last week, KKR-owned ContourGlobal announced that it had acquired 1.6 GW of battery energy storage projects in Italy with up to 9.5 GWh of energy storage capacity ahead of the first MACSE auction in September. The entire portfolio is expected to be commissioned in 2028, according to the company.

Only a day after announcing its big move in the Italian market, Bison Energy revealed it had signed Japan’s first 10-year revenue floor agreement for battery storage. The specific assets covered by the agreement were not disclosed.

The deal was signed with Engelhart, a London-headquartered energy trading and asset optimization company. Under the agreement, Bison Energy, through its wholly-owned asset owning subsidiaries, will receive a fixed minimum revenue for its BESS assets, while also participating in upside sharing when market conditions exceed floor levels.

Drawing on its experience in managing battery storage portfolios in deregulated European markets, Engelhart will oversee real-time asset dispatch, charge-discharge strategy, and revenue maximization tailored to Japan’s power market.

“This structure provides the financial certainty developers and investors need to accelerate BESS deployment in Japan,” said Michael Zhang, CEO at Bison Energy.

Bison Energy is targeting more than 2.4 GW/10 GWh of utility-scale battery storage in Japan by 2030. The company was awarded 240 MW across three projects in the second round of the Long-Term Decarbonization Auction (LTDA) for a total of 1 GWh of capacity.

According to the auction results published on April 28, 27 projects were awarded contracts as part of the capacity market totalling 1.4 GW. Six of these projects are designed for durations of six hours or longer, while 21 are for batteries with durations between three and six hours.

BESS was the most oversubscribed technology in Japan’s second LTDA round, with only 20% of the bid capacity awarded.