Though CAES requires a suitable geological location, it is possible to construct the air storage and both CAES plants mentioned here use a solution-mined salt cavern as air storage location. In addition to the utility scale CAES systems, a small scale adiabatic 2 MW, 500 MWh storage plant was commissioned in Gaines, Texas in late 2012 (General Compression, 2014). A demonstration plant operating on the adiabatic CAES principle is scheduled for completion in 2016 (RWE Power AG, 2010).