Novel Approaches to Utility Energy Storage
The advantage of underground compressed air storage is that it can be cheaper than batteries and can store many hours worth of energy. Another novel technique is using metal tanks to store compressed air. The compressed air is released to run a hydraulic motor that drives a generator to make electricity. Flow batteries use tanks of liquid electrolyte solutions. When the two liquids interact, there is a chemical reaction that creates a flow of electricity. An advantage of this approach is that store large amounts of energy and discharge relatively quickly.