The move comes as utilities step up efforts to decarbonise their facilities to combat global warming.
Japan's second-biggest coal-fired power generator after JERA will permanently close the No.1 plant and suspend the No.2 plant at the end of March 2025, though it will build a gasification facility at the No.2 plant to restart it in 2028 with greater efficiency and lower emissions.
"Through the closure and suspension, we will be able to achieve our 2025 target of cutting CO2 emissions by 9.2 million tonnes, or 19%, on 2013 levels," President Hitoshi Kanno told a news conference, noting it will also increase the use of biomass and cut the utilisation rate of other coal power plants.
"We will continue operation in Matsushima with an aim of making it as a leading carbon-free thermal power plant in Japan by using biomass and ammonia fuels as well as deploying carbon capture utilisation and storage (CCUS) in the future," he said.
After implementing the gasification technology, the reformed No.2 plant will be able to reduce its emissions by more than 10%, he said.
J-Power, which owns coal-fired plants at nine sites with total generation capacity of 8.8 gigawatts (GW), will consider downsizing some coal power plants and converting others to CO2-free power plants, Kanno said.
For the current fiscal year to end-March, the company lowered its net profit estimate by 12% to 67 billion yen from 76 billion yen due to lower electricity sales, falling power prices overseas and a glitch at one of its local power plants.