Wind power constituted 25 percent of all US generation capacity
additions during 2017. Wind energy contributed 6.3 percent of
the nation's electricity supply, more than 10 percent of total
electricity generation in 14 states, and more than 30 percent in
four of those states (Iowa, Kansas, Oklahoma, and South Dakota).
Lower installed project costs, along with improvements in
capacity factors, are enabling aggressive wind power pricing
from 7 cents per kWh in 2009 to around 2 cents per kWh during
2017.