The Iowa Stored Energy Plant (ISEP) will be the first plant in the world that will use energy from a wind farm plus supplemental off peak electricity to produce compressed air to be stored in an underground aquifer until it is need to produce electricity on demand. When demand for electricity is high, the air will be released and used in combination with a small amount of natural gas to drive combustion turbines to generate electricity. Wind power is undependable and not always available when needed, compressed air energy storage (CAES) mitigates this intermittency.