Energy Vault buys 850 MW Japanese BESS portfolio from BayWa r.e.

Energy Vault has announced the successful completion of its acquisition of an 850 MW battery energy storage system (BESS) development portfolio in Japan from BayWa r.e..

The deal was first announced on April 9 2026, where Energy Vault said it had a binding agreement to acquire Japanese assets, but didn’t name the portfolio seller at the time.

The assets includes 350MW of sites expected to reach notice to proceed (NTP) in 2027, and commercial operations targeted for 2028, with 500MW of “early-stage projects” also included. The “advanced-stage projects” are “expected to be configured with three hours of storage duration,” implying a 1.05 GWh capacity.

Energy Vault said it officially establishes Energy Vault’s operational presence in Japan, and provides it with “an immediate in-country platform, a premium project pipeline, and a highly experienced local development team with deep expertise in land rights, regulatory permitting, and utility interconnections”/erm owned-asset platform in a market with strong demand for flexible, reliable, and dispatchable energy storage.

Robert Piconi, chairman and chief executive ffficer of Energy Vault, said, “By completing this acquisition, we have secured not only a premium BESS development portfolio, but also an experienced local team from one of the most respected renewable energy platforms globally in BayWa Renewables.”

Daniel Gaefke, group chief operating officer of BayWa r.e, added, “This transaction reflects BayWa r.e.’s ability to originate, develop, and monetize premium renewable energy assets globally.”