China wasted enough wind and solar power in the first half of this year to cover all new electricity demand, according to a report, as bottlenecks in grid absorption failed to stem a rebound in coal-fired generation.Though solar is poised to overtake coal as China’s largest source of installed power, an estimated 360 terawatt-hours of wind and solar electricity was curtailed in the first half – up 49 per cent year on year – according to a report released on Thursday by the Finland-based Centre...