The project is the result of a joint venture between Sumitomo and Nissan, who formed a company called 4R Energy Corporation in September 2010 to investigate ways to reuse electric vehicle batteries after their on-road life is finished.

It is hoped that the facility, which uses 16 Nissan LEAF lithium-ion batteries, will allow the usually variable output from the solar farm on Yume-shima Island to be balanced. Sumitomo is hoping to open further facilities elsewhere in Japan.

Battery business development department general manager, Norihiko Nonaka said: ‘We are pleased to be a part of such an important verification project that can both utilize used EV batteries, and provide a large-scale power storage facility, which are important issues that need to be addressed for the future of renewable energy.’