Method and apparatus for storing mechanical energy by quasi-isothermal expansion and compression of a gas

摘要

A system for energy storage, in particular for mechanical energy, including a system for quasi-isothermal compression of a gas via a hydraulic fluid. The mechanical energy stored is then released by quasi-isothermal expansion of the gas. The system is also configured to store electrical energy, in particular from intermittent sources such as photovoltaic or wind energy. The storage of excess electrical energy can also be considered for use during consumption peaks.

主权项

1. A system for storing energy comprising:
a first chamber; a thermal energy storage medium contained in the first chamber; at least one container containing a hydraulic fluid and a gas; at least one storage chamber containing the hydraulic fluid; and compression-expansion means configured to operate between a compression mode which pumps the hydraulic fluid and an expansion mode which expands the hydraulic fluid, wherein:
at least one of the hydraulic fluid and the gas contained in the at least one container is in thermal contact with the thermal energy storage medium;the at least one container is fluidically connected to the at least one storage chamber by lines which enable the hydraulic fluid to be transported between the at least one container and the at least one storage chamber, across the compression-expansion means; andthe compression-expansion means is configured to pump the hydraulic fluid from the at least one storage chamber to the at least one container, and also configured to expand the hydraulic liquid contained in the at least one container toward the at least one storage chamber, to thereby generate mechanical energy, and wherein the at least one container comprises a spiral tube.