Japan Selects 1.25GW of Battery Storage in Capacity Auction as 67% of 10.9GW Bids Win
Updated
Updated · Energy-Storage.news · May 19
Japan Selects 1.25GW of Battery Storage in Capacity Auction as 67% of 10.9GW Bids Win
1 articles · Updated · Energy-Storage.news · May 19
OCCTO awarded 19 battery storage projects totaling 1,251MW in Japan’s third Long-Term Decarbonisation Power Sources Auction, with 20-year fixed-revenue contracts starting in fiscal 2027.
The round was limited to batteries of at least 6-hour duration and added JC-STAR cybersecurity certification plus a rule capping cells from any one foreign country at 30% of awarded capacity, factors seen reducing bids.
Total bid capacity reached 10.9GW, with 67% successful; the auction also selected 453MW of pumped hydro, 264MW of ammonia co-firing, 253MW of hydrogen-only generation, 1.38GW of new or refurbished nuclear and 3GW of LNG.
Repeat battery winners included Stonepeak affiliates, CHC, Bison Energy and Hexa Energy Services, underscoring continued investor interest as Japan uses the LTDA to add longer-term clean capacity beyond its main security-of-supply market.
Can Japan's domestic industry meet demand as new rules cap foreign battery cells for grid storage?
By awarding 3GW to natural gas, is Japan's decarbonization auction undermining its own climate goals?
Is Japan overlooking cheaper software solutions for its grid by focusing billions on new power hardware?
Japan’s 2026 Power Market: Decarbonization Auction Results, Battery Storage Economics, and Grid Bottlenecks
Overview
Japan's 2026 Long-Term Decarbonization Electricity Capacity Auction marked a pivotal step in the country's energy transition. Nuclear projects secured the largest share of awards, highlighting their central role in Japan's decarbonization strategy. For the first time, hydrogen-only thermal power plants also received contracts, signaling a new milestone in diversifying clean energy sources. Additionally, two pumped hydro storage projects were awarded, emphasizing the ongoing importance of large-scale energy storage for grid stability and renewable integration. Together, these outcomes reflect Japan's evolving approach to building a greener, more resilient power system.