U.S. wind power accounted for 6 percent of the nation's total electricity generation capacity after developers rushed to finish projects before expiration of a subsidy, Bloomberg New Energy Finance said. The threat that the U.S. Production Tax Credit would lapse on Dec. 31 prompted developers to complete as many projects as they could last month, the London-based research group said. A record 13.2 gigawatts of turbines were installed last year, including 5.5 gigawatts in December, the most ever for a single month. Total wind generation capacity is about 60 gigawatts. The tax credit has been extended for projects that will launch this year. Read more.