Twenty years ago, wind energy was mostly a niche industry that contributed less than 1% to the total electricity demand in the United States. Wind has since emerged as a serious contender in the race to develop clean, renewable energy sources that can sustain the grid and meet the ever-rising global energy demand. Last year, wind energy supplied 7% of domestic electricity demand, and across the country—both on and offshore—energy companies have been installing giant turbines that reach higher and wider than ever before.