The Associated Press reports that “a proposal to export twice as much Wyoming wind power to Los Angeles as the amount of electricity generated by the Hoover Dam includes an engineering feat even more massive than that famous structure: Four chambers, each approaching the size of the Empire State Building, would be carved from an underground salt deposit to hold huge volumes of compressed air.”  

“The caverns in central Utah would serve as a kind of massive battery on a scale never before seen, helping to overcome the fact that — even in Wyoming — wind doesn’t blow all the time.”  

“Air would be pumped into the caverns when power demand is low and wind is high, typically at night. During times of increased demand, the compressed air would be released to drive turbines and feed power to markets in far-away Southern California.”