Hydrostor Building Underground Caverns for Affordable Compressed-Air Energy Storage

Hydrostor, the Canadian company that wants to store energy as compressed air in large balloon-like bags underwater, is now turning its attention to terra firma. Specifically, the company unveiled a system to store large-scale energy in underground compressed-air caverns.

The system comes in at “half the cost of competing battery technologies, and on part with new natural gas plants,” the company claims.

The case for storing large quantities of electrical energy is getting stronger and stronger, whether to expand the use of solar and wind power or to meet surges in demand on the grid. Batteries are making headway for energy storage, but compressed-air energy storage (CAES) is a strong contender.  Such systems use off-peak electricity to run compressors and store the compressed air, which can later be expanded to drive a turbine.

CAES systems have the potential to cost less and last longer once they have been built.  The problem with conventional CAES is that it is expensive and requires underground geological formations to store the air.
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Hydrostor might have competition from a few other CAES startups looking to enter the market. SustainX in New Hampshire has demonstrated a full-scale system to store compressed air in pipes, while LightSail Energy plans to store air in steel tanks.

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