Google invests in carbon dioxide battery for renewable energy storage

Google has announced that it has signed a global commercial partnership with Milan-based startup Energy Dome and has also invested in its long duration energy storage (LDES) tech for renewable energy. The deal, its first investment in LDES tech, entails using Energy Dome's carbon dioxide battery for the grids that power Google’s operations around the world. Batteries are used to keep excess energy generated by renewable sources, such as solar and wind, during peak production and when demand is low. But lithium-ion batteries can only store and dispatch energy for fours hours or less.

Energy Dome explained that its CO2 battery can store and continuously dispatch energy for 8 to 24 hours, so Google can rely on renewable power more even when there's no wind or sun. Its technology uses carbon dioxide held inside dome-shaped batteries, which you can see in the image above. When there's excess renewable energy being generated, the batteries use that power to compress the carbon dioxide gas inside them into liquid. And when that energy is needed, the liquid carbon dioxide expands back into a hot gas under pressure. That gas spins a turbine and generates energy that's fed back into the grid for a period lasting up to a whole day. 

Google said that Energy Dome's technology has the potential to "commercialize much faster" than some of its other clean tech investments, and it aims to "bring this technology to scale faster and at lower costs." It also said that it believes the partnership and its investment in Energy Dome can help it achieve its goal of operating on renewable energy 24/7 by 2030.