Google and Energy Dome ink deal for 23MW/200MWh CO2 battery project in Ireland

Google and Energy Dome announced a bilateral commercial agreement for a new CO2 battery project in Ireland, with the planned system sized at 23 megawatts (MW) and 200 megawatt-hours (MWh) of energy storage.

The project is slated for County Offaly, according to the announcement carried by Yahoo Finance. The deal follows growing interest from energy companies and technology firms in long-duration energy storage, which is designed to store electricity for extended periods rather than for only minutes or hours.

A CO2 battery, in broad terms, is an energy storage approach that uses carbon dioxide as the working fluid. The system typically shifts between storing energy and delivering energy by changing the physical state of CO2, enabling electricity to be put into the storage during charging and retrieved during discharge. Companies pursuing these designs argue they can help manage grid variability from wind and solar generation by supplying power when output is lower.

For Alphabet, the arrangement fits within the company’s stated focus on large-scale infrastructure and energy procurement for data centers and other operations, where reliability and cost stability matter. For Energy Dome, partnerships with major technology and energy buyers can be important for scaling deployments, as long-duration storage projects are capital-intensive and require committed offtake and development support.

While the announcement confirms the project’s headline capacity and location, it does not provide, in the information available here, additional deal terms such as the length of the agreement, whether Google is acting as a buyer of stored power, or the expected timeline for construction and commissioning.

It also does not disclose the specific market the project would serve, for example whether it is intended primarily for electricity arbitrage, grid balancing services, or a dedicated power supply arrangement tied to a customer portfolio. Such details can affect how quickly a project reaches revenue and how risks are allocated between developers and customers.

In the absence of those particulars, the most observable takeaway is that a global technology firm is directly aligning with a storage developer on a project that is large by grid-storage standards. The planned 200MWh scale suggests the parties are aiming beyond pilots, toward a deployment that can demonstrate performance and commercial viability at a meaningful size.

Next, investors and grid stakeholders will likely look for follow-up disclosures that typically accompany deals of this type, including final project financing, permitting and interconnection milestones in Ireland, and clearer terms around ownership, operation, and how stored capacity will be valued. Without those disclosures, the near-term scope of the commercial commitment remains the central uncertainty.