Renova and its partners began commercial operation of the 49.9MW Karatsu Biomass Power Plant in Karatsu City, Saga Prefecture, on September 27, 2025, following multiple delays, the company announced on September 30, 2025.
According to the statement, the project was converted from the feed-in-tariff (FIT) scheme to the feed-in-premium (FIP) scheme to enable a long-term fixed-price PPA with an undisclosed offtaker. It was first certified in FY2017, when large-scale woody biomass power plants were offered a 24 yen per kWh tariff for 20 years.
The asset is expected to generate about 350GWh annually using imported wood chips and palm kernel shells (PKS).
In addition to Renova, which owns a 35% economic interest in the project’s special purpose company (SPC) Karatsu Biomass Energy LLC, Toho Gas holds 34%, JA Mitsui Lease 16%, and INNOCENT 15%. Renova retains an option to reacquire JA Mitsui Lease’s share.
The four partners made the final investment decision on the project in August 2021. Construction started during the same month and was initially scheduled to be completed in December 2024. Planned completion was first delayed to March 2025 before being pushed back to September 2025. Nippon Steel Engineering handled engineering, procurement, and construction (EPC) and Kansai Electric Power was in charge of owner’s engineering.
Karatsu is Renova’s seventh biomass power plant, bringing its total portfolio to about 445MW unadjusted for ownership share. It follows the 75MW Omaezaki Port Biomass Power Plant that the developer commissioned jointly with Chubu Electric Power and other partners in January 2025. Toho Gas has also participated in multiple projects including the 112MW Tahara Biomass Power Plant commissioned in September 2025, in which it holds a 10% stake.
