Storing solar and wind energy with compressed air. Researchers have studied the potential of using compressed air to store renewable energy in offshore saline aquifers. The technology could hold 77-96 TWh for up to two months in British waters, although the costs have proven hard to pin down. Salt-water aquifers under British waters could hold 77-96 TWh of renewable-energy-powered compressed air for the two-month windows required of seasonal energy storage, according to a study conducted by the University of Edinburgh. An investment of $16-59 million in 6,300-7,800 such offshore wells could achieve storage efficiency of 54-59%, according to the Edinburgh researchers, with the resulting electricity having a levelized cost of $0.42-4.71/kWh.
PV Magazine 5th May 2020 read more »