Nihonkaisui will replace an existing coal-fired power plant at its Sanuki Factory in Sakaide City, Kagawa Prefecture, with a biomass power plant using METI’s subsidy for promoting investment in energy conservation, its parent company Air Water announced on August 26, 2025.
According to the statement, construction work on the 9.4MW Sanuki Biomass Power Plant is expected to begin in FY2026, with commissioning scheduled for FY2028. Nihonkaisui plans to invest about 14 billion yen in the project, including 4 billion yen covered by the subsidy. Once operational, the power plant will use about 14,000 tons of domestic construction waste, bark, thinned wood, and imported fuel annually.
The company, which holds an approximately 40% market share in domestic salt production, has historically operated coal power plants at its factories due to the energy-intensive manufacturing process. It completed its first biomass power plant, a 16.5MW asset in Ako City, Hyogo Prefecture, in 2015, and has continued to expand its portfolio ahead of the planned introduction of a fossil fuel surcharge in FY2028 under the GX Promotion Act.
In 2021, it added another 30MW biomass plant in Ako, followed by a 50MW facility in Kanda Town, Fukuoka Prefecture, in 2023. Its parent Air Water also owns 1.9MW and 75MW assets in Nagano and Fukushima prefectures, respectively. All five projects operate under the feed-in-tariff (FIT) scheme.
