Not just blowing in the wind: Compressing air for renewable energy storage

[OKIsItJustMe]

3. Naturally there are losses… the question is whether they are acceptable or not

However:

http://www.pnnl.gov/news/release.aspx?id=985

…

The world's two existing compressed air energy storage plants — one in Alabama, the other in Germany — use man-made salt caverns to store excess electricity. The PNNL-BPA study examined a different approach: using natural, porous rock reservoirs that are deep underground to store renewable energy.

…

http://www.powersouth.com/mcintosh_power_plant/compressed_air_energy

[font face=Serif][font size=5]CAES[/font]

[font size=4] Located in McIntosh, Ala., the 110-megawatt Compressed Air Energy Storage (CAES) facility is PowerSouth’s most unique generating source.[/font]

[font size=3]The PowerSouth CAES unit was declared commercial in 1991. It is the only one of its kind in the U.S. and one of only two in the world. The other CAES unit is located in Huntorf, Germany.

The unit captures off-peak energy at night, when utility system demand and costs are lowest. Compressors force air into an underground storage reservoir at high pressure. PowerSouth uses the stored energy during intermediate and peak energy demand periods to generate electricity.

At full capacity, the CAES facility produces enough electricity to power approximately 110,000 homes.

The CAES plant burns roughly one-third of the natural gas per kilowatt hour of output compared to a conventional combustion turbine, thus producing only about one-third the pollutants.[/font][/font]

(Video available at the site.)