Japan’s Kansai Electric announced plans to construct the country’s largest energy storage facility on the site of a retired oil-fired power plant in Osaka. Slated to open by 2027, the $300 million-plus project aims to stabilize Japan’s growing renewable energy grid and prevent blackouts caused by unpredictable wind and solar power.

　The massive battery will store 400,000 kilowatt-hours of electricity—enough to power 46,000 households for a day. Built over 21,500 square feet, it’s triple the size of Kansai’s existing storage site in Wakayama, which cost $53.6 million and powers 13,000 homes.

　Japan’s push for green energy faces a hurdle: sunny or windy days produce excess power, while cloudy or calm periods strain supply. Utilities like Kansai have increasingly halted renewable operations to avoid grid overloads. “This battery acts as a buffer,” a company spokesperson said.

　The project aligns with corporate demand. Telecom giant KDDI, for example, plans an AI data center in Osaka fully powered by renewables—a feat impossible without large-scale storage.

　Kansai also eyes a third storage site in Hokkaido, signaling Japan’s race to balance its clean energy ambitions with reliability.