Google has signed its first partnership with a long-duration energy storage (LDES) company.

The tech giant signed a long-term partnership with Energy Dome to support multiple commercial deployments worldwide to help scale the company’s CO2 battery technology.

The Milan-based LDES firm has developed a novel CO2 battery, which utilizes CO2 held in a unique dome-shaped battery. The system is deployed when renewable energy is abundant on the grid and uses the power to compress CO2 gas into a liquid. When the grid requires more power, the liquid CO2 expands back into a hot gas under pressure, which spins a turbine that can feed energy back into the grid for periods ranging from eight to 24 hours.

The company has developed a 20MW/200MWh battery, which it claims has a lifetime of more than 30 years. According to Energy Dome, the technology does not rely on any critical minerals, only using water, steel, and CO2. It has a deployment time of under two years, with every component used in the system standard, which improves economies of scale.

Google has said it believes the commercial partnership will play a significant role in unlocking “new clean energy for grids where we operate before 2030, helping meet near-term electricity system needs and moving us closer to our 24/7 carbon-free energy goal.”

“The programmatic and strategic deployment of our technology at scale to help Google reach carbon-free energy represents the core of our industry-first agreement. We’re proving that a 24/7 cost-effective and carbon-free energy supply is achievable with the right technology and partnership model,” said Claudio Spadacini, founder and CEO of Energy Dome.

In addition to the commercial partnership, Google has also made a direct investment in the company. The partnership is part of a broader push by Google to invest in LDES technology. It plans to support a growing range of LDES technologies currently under development through both commercial agreements to support more mature technologies, such as Energy Dome’s, in addition to earlier-stage investments.

Energy Dome has several deployments already underway. Last year, it signed its first supply contract within the US market with Alliant Energy. It has also signed an offtake agreement with renewable energy firm Engie to supply power from its first commercial deployment in Ottana, Sardinia, Italy.

In addition to the partnership, Google has also said it intends to advocate for clean energy policies to remove barriers to the deployment of LDES technologies. The deal with Energy Dome is seen as a first step for the company to catalyze the growth of the sector and support its adoption across the data center market.

While this is the first deal with an LDES firm, Google has backed a number of battery energy storage (BESS) companies, utilizing the technology across its data center portfolio. For example, in April 2022, it reported that it was using a 2.75MW BESS system supplied by Fluence to replace some of the diesel backup capacity at its St. Ghislain, Belgium data center.