Associated Press: China could cut its emissions by 30 percent in the next two decades if it switches to wind power to meet about half of its electricity demands, a U.S. study published Thursday said. China’s energy needs are expected to double by 2030, but the study in the journal Science says that the country could reasonably meet half of those needs with wind. Using meteorological data to assess the potential for wind power in China– the world’s largest emitter of carbon dioxide — the …