Goto, Japan: As Japan drives to make renewables its top power source by 2040, the country sees offshore wind energy as its key “trump card”. Eight turbines — sitting five kilometres (three miles) off the coast of the Goto Islands in waters up to 140 metres deep — will officially start turning in January next year. “Floating structures are relatively stable even in the case of earthquakes or typhoons,” says Kei Ushigami, head of marine renewable energy for construction company Toda, a key player in the project.