Defying conventional wisdom about the limits of wind power, in 2012 both Iowa and South Dakota generated close to one quarter of their electricity from wind farms.
Wind energy accounted for at least 10 percent of electricity generation in seven other states.
Across the United States, wind power continues to strengthen its case as a serious energy source.
The United States now has 60,000 megawatts of wind online, enough to meet the electricity needs of more than 14 million homes.
A record 13,000 megawatts of wind generating capacity was added to the country