Google invests in long-duration battery in pursuit of 24/7 carbon-free power

Google has partnered with Italian firm Energy Dome to deploy a type of long-duration battery in its pursuit of 24/7 carbon-free electricity.

Energy Dome’s ‘CO2 Battery’ stores excess energy generated from renewable sources, and is able to dispatch it back to the grid for 8 to 24 hours. This means solar and wind energy can be used even when these resources are not available, essentially bridging the gap between renewable generation and consumption.

The Italian startup’s novel approach to energy storage uses CO2 held in a dome-shaped battery, so that when there's an abundance of renewable energy on the grid, that power is used to compress the CO2 into a liquid. When the grid needs more power, the liquid CO2 expands back into a hot gas under pressure, creating a force that spins a turbine. This spinning turbine generates carbon-free energy that can flow directly back into the grid.

“Google is committed to powering our operations with clean energy, and Energy Dome’s technologically proven and scalable long-duration energy storage solution can help us unlock rapid progress,” said Maud Texier, Director of EMEA Energy at Google. 

Long-duration energy storage

While lithium-ion batteries have been critical for stabilising renewable energy loads and deploying zero-carbon transportation, their duration (around four hours) is not suitable for time-shifting – allowing renewable energy to be used in times when resources are unavailable.

Long-duration energy storage (LDES) such as the CO2 battery developed by Energy Dome could help cost-effectively integrate a growing volume of renewables onto power systems and contribute to more flexible, reliable grids.

It’s estimated that deploying up to 8 terawatts (TW) of LDES by 2040 could result in US$540 billion in annual savings globally.

“This isn’t just about Google. By helping to scale this first-of-a-kind LDES technology, we hope to help communities everywhere gain greater access to reliable, affordable electricity and support grid resilience as we integrate more renewable energy sources,” added Texier.

With this investment, Google will support multiple commercial deployments of Energy Dome’s technology globally, with the goal of helping the technology to scale faster and at lower costs. The tech giant also plans to support other types of LDES technologies under development.