A research group at University of Arizona is pursuing three projects using Compressed Air Energy Storage (CAES) to supplement wind and solar energy sources. The group is "developing cost-competitive energy-storage systems based on compressing air and storing it in man-made containers or below ground in natural reservoirs."
"When solar panels shut down and wind generators stop spinning, the compressed air is heated slightly and released to drive turbines that generate electricity. The compressed air also can be released directly to drive mechanical systems without being converted to electricity."In one of the projects, "researchers in the UA's Laboratory for Advanced Subsurface Imaging, or LASI, are developing high-resolution underground imaging systems that can be used to find salt deposits, porous rocks and other natural underground storage reservoirs. These sites could be used to hold large amounts of compressed air to drive utility-scale turbines."
Arizona has large widespread subsurface salt deposits that might serve as CAES reservoirs.
[right, CAES researchers stand next to a receiving coil used by the Laboratory for Advanced Subsurface Imaging to conduct underground imaging. Left to right are ECE professor Steve Dvorak, MSE technical staff member Bennett Meulendyk, ECE graduate student Alex Jacobs, and LASI director Ben Sternberg, professor geological & geophysical engineering and electrical & computer engineering. Credit, UA]
[based on the UA news release]