Google Partners with Energy Dome to Deploy CO2 Battery for Clean Energy Storage

Mountain View, CA – August 7, 2025 – Google has announced a groundbreaking partnership with Italian startup Energy Dome to deploy innovative CO2-based batteries for long-duration energy storage (LDES), aiming to power its global operations with 24/7 carbon-free energy by 2030. This marks Google’s first commercial investment in LDES, a critical step to address the intermittency of renewable energy sources like solar and wind, particularly for its energy-intensive data centers and AI operations. The collaboration, which includes an undisclosed strategic investment in Energy Dome, is set to roll out projects in Europe, the U.S., and Asia-Pacific, with a commercial-scale facility already planned in Sardinia, Italy.

How the CO2 Battery Works

Energy Dome’s CO2 Battery uses carbon dioxide in a closed-loop system to store and dispatch clean energy for 8 to 24 hours, far surpassing the four-hour limit of traditional lithium-ion batteries. When renewable energy production is high, the system compresses CO2 gas into a liquid, storing it in carbon steel tanks. When energy demand rises—such as at night or during low wind—the liquid CO2 is heated, expanding back into a gas to spin a turbine, generating electricity. The CO2 is then recaptured in a dome-like structure for reuse, ensuring no emissions are released. The system’s rotating machinery also provides grid inertia, stabilizing power flow as fossil fuel plants retire.

This technology, already operational at a 20-megawatt, 200-megawatt-hour plant in Italy for over three years, uses off-the-shelf components, making it cost-effective and scalable compared to lithium-ion systems, which rely on scarce materials like cobalt and nickel. Google’s director of EMEA Energy, Maud Texier, stated, “Energy Dome’s proven and scalable solution can help us unlock rapid progress toward our 24/7 carbon-free energy goal.”

Addressing Renewable Energy Challenges

Wind and solar power, while cost-competitive, are unreliable without robust storage to bridge gaps during low production. Google, one of the world’s largest corporate buyers of renewable energy, consumed 15.5 terawatt-hours annually as of 2022, primarily for its data centers. The CO2 Battery’s ability to store energy for up to a full day supports Google’s operations, including AI systems, and enhances grid reliability for communities. The LDES Council estimates that deploying 8 terawatts of LDES by 2040 could save $540 billion annually by optimizing renewable integration.

Energy Dome’s projects, including partnerships with Alliant Energy in the U.S., Engie in Italy, and NTPC in India, are in early development, with Google’s backing expected to accelerate global deployment. Unlike other clean energy technologies in Google’s portfolio, such as geothermal or fusion, the CO2 Battery’s reliance on existing supply chains enables faster commercialization.

Industry Context and Public Sentiment

The partnership comes as the cyber insurance market highlights systemic risks in interconnected systems, including energy grids, underscoring the need for stable power solutions. Google’s move contrasts with competitors like Tesla, whose Megapack batteries focus on shorter-duration storage. CleanTechnica notes that the CO2 Battery could challenge both fossil fuel plants and other battery technologies by enabling greater use of renewables. On X, users like @cb_doge emphasize the massive scale of battery demand, with U.S. grid output at 1 terawatt, highlighting the urgency of scalable solutions like Energy Dome’s.

Critics, however, question the technology’s long-term impact. Some X posts express skepticism about CO2-based systems, citing the need for more data on efficiency and environmental trade-offs. Others, like @JohnLeePettim13, note material constraints in battery innovation, though Energy Dome’s use of abundant CO2 and standard components mitigates this concern.

Looking Ahead

Google’s investment aligns with its broader clean energy strategy, including 8 gigawatts of renewable contracts signed in 2024 and efforts to reduce data center emissions through efficient infrastructure (average PUE of 1.09 vs. industry 1.56). The Sardinia pilot, if successful, could pave the way for widespread adoption, supporting not just Google but entire grids transitioning from fossil fuels. As Energy Dome’s CEO Claudio Spadacini said, “A 24/7 cost-effective and carbon-free energy supply is achievable with the right technology and partnership.”

For more details, visit Google’s sustainability blog or Energy Dome’s website at www.energydome.com.