Compressing air to store energy is nothing new: for decades, several facilities around the world have pumped air into huge underground caverns under pressure and then used it to generate electricity. electricity in a natural gas power plant. But the Energy Dome turned to carbon dioxide because of its physical properties.
Carbon dioxide, when forced to a high enough pressure, turns into a liquid, something air cannot do unless cooled to extremely low temperatures. Liquid carbon dioxide could fit into smaller steel tanks near where renewable energy is generated and used.
In the design of the Energy Dome, a flexible membrane holds carbon dioxide in a giant dome at low pressure. When there is excess power, the gas will pass through the compressor to reach high pressure. This process also generates heat, which is also stored.
Then, when energy is needed, the stored heat is used to heat carbon dioxide, which decompresses and turns a turbine, generating electricity.
