Wind power is the world’s most developed renewable energy source after hydroelectric dams, but it has one big problem — wind doesn’t blow at the same speed all the time, making variable output from wind turbines hard to integrate into the electricity grid.

Japan Steel Works is aiming to ease that problem by building wind turbines with batteries included in them, according to Nikkei via Asia Pulse. The maker of steel products including nuclear plant pressure vessels plans to start selling the turbines, built in conjunction with battery manufacturer Meidensha Corp. next year, according to news reports. Read More