The CryoHub project will use extra wind and solar electricity to freeze air to cryogenic temperatures, where it becomes liquid and in the process shrinks by 700 times in volume. The liquid air is stored in insulated low-pressure tanks similar to ones used for liquid nitrogen and natural gas.

When the grid needs electricity, the subzero liquid is pumped into an evaporator where it expands back into a gas that can spin a turbine for electricity. As it expands, the liquid also sucks heat from surrounding air. “So you can basically provide free cooling for food storage,” says Judith Evans, a professor of air-conditioning and refrigeration engineering at London South Bank University who is coordinating the CryoHub project. //

The U.K. is already a leader in liquefied air energy storage (LAES) technology. London-based Highview Power put the first-ever LAES system online last summer. The 5-MW demonstration plant near Manchester is designed to power 5,000 homes for about 3 hours.