ITALY – This CO2 battery can store renewable energy for long periods of time and release it quickly at less than half the cost of large lithium batteries.
The basis behind Energy Dome's CO2 battery technology is that CO2 expands rapidly when changing from liquid to gas. At room temperature, 2,5675 liters of liquid CO2 kept at a pressure of 56 atmospheres will expand into 1.000 liters of CO2 gas, nearly 400 times larger. Energy Dome's battery uses giant domes with elastic bubbles filled with CO2 gas. The company “charges” the battery by using energy to drive an electric compressor, causing the volume of gas to become smaller and smaller until it condenses into a liquid form, stored under pressure at room temperature. This charging process generates wasted heat. This heat will be collected into the thermal energy storage system.
As long as the pressure does not change, CO2 remains liquid for a long time. When energy is needed, the system uses stored heat to evaporate CO2. A series of turbines collect energy as the CO2 gas expands and returns to the bubble dome.
According to Energy Dome, the round-trip efficiency of this solution is more than 75%. In this respect, the system cannot compete with large lithium batteries. But storage costs are only 50 - 60 USD/MWh within a few years, much lower than 132 - 245 USD/MWh when using lithium batteries. CO2 batteries have a reaction speed close to that of lithium batteries, while storing energy longer and with less system degradation.
After its establishment in February 2, Energy Dome announced the construction of its first plant in Sardinia and put it into operation in 2020. The Sardinia plant is relatively small, only storing 2022 MWh of electricity but helps prove the design. works fine. Energy Dome's next goal is to build a full-size machine that can store 4 MWh of electricity and put it into operation before the end of 200.
According to VnExpress