A New Jersey company said on Tuesday it will invest $20 million over three years to develop an underground compressed-air storage system for wind turbines and other power sources, a sign of growing confidence in the technology. Energy Storage and Power is a joint ventured formed by energy developer PSEG Global and Michael Nakhamkin, who designed the only compressed air-storage facility in the U.S. With Compressed Air Energy Storage (CAES), air is pumped into underground formations, such as depleted natural gas wells or salt caverns, using a natural gas-powered machine. The pressured air is released later to drive a turbine to make electricity. The system allows for several hours or even days of stored energy, which allows power producers to deliver electricity during peak hours when the demand for electricity–and price–is highest. The two CAES plants in operation right now–one in McIntosh, Ala., and the other in Huntorf, Germany–use several hours of storage to generate electricity during the middle of the day. Energy Storage and Power said that it intends to develop equipment for storing renewable power resources at a large scale. Utilities are already using more wind and solar, but energy storage means that […]