American Wind Energy Association: U.S. Wind Industry Fourth Quarter 2015 Market Report (pdf)
Excerpt: The American Wind Energy Association‘s fourth quarter report states that Iowa now has the second-highest wind energy capacity of any in the nation behind Texas.
Iowa now has 6,212 megawatts of wind energy capacity. The state added over 500 megawatts of capacity in the fourth quarter of 2015. The report also states that there is less than 250 megawatts currently under construction in the state.