Wikipedia has rather more information on this, including (in the History section) a bunch of examples of this at scale going back to the 70s http://en.wikipedi

Wikipedia has rather more information on this, including (in the History section) a bunch of examples of this at scale going back to the 70s http://en.wikipedia.org/wiki/Compressed_air_energy_storage http://en.wikipedia.org/wiki/Compressed_air_energy_storage