Compressed air can be used to produce mechanical work. When there is a demand for electricity, air is used which has been previously compressed and stored for moving a turbine with a generator produces electricity. One advantage of the solution is to generate only low risk (no or little toxic, rare metals, etc.) and have no geographical constraint (decentralized solution) or scale dice when a source electricity is available.
Various solutions have been tested or explored, to store intermittent energy from renewable sources.