Rhode CO2 Battery

Executive Overview

Energy Dome and Google announced on 23 June 2026 their first bilateral commercial contract: a 23 MW / 200 MWh CO2 Battery long-duration energy storage project near Rhode, County Offaly, in the Irish Midlands. Energy Dome will develop, own and operate the facility, which is being built on the site of a former peat-fired thermal power station — a brownfield redevelopment — in collaboration with local Midlands company Lumcloon Energy. The project is expected to begin operating in 2028.

How It Works & Differentiation

The CO2 Battery stores surplus renewable electricity by compressing and storing carbon dioxide, then expands it through a turbine to dispatch power during periods of high demand or grid stress, helping relieve congestion on the local network. Building on a brownfield peat plant site with existing planning consent, land rights, and a grid connection meaningfully reduces development risk and timeline compared to a greenfield site.

Commercialization & Traction

The site already has planning consent, land rights and a grid connection, and EirGrid — Ireland's state-owned transmission system operator — has awarded a 10-year capacity contract. A second 200 MWh unit is also planned at the location.

Scalability & Strategic Context

The project forms part of the broader Google–Energy Dome partnership announced in 2024 to deploy CO2 Battery technology across Europe, North America and Asia-Pacific, and follows the Coronado CO2 Battery project in Arizona (with utility SRP). Rhode is therefore one node in a multi-continent Google-backed CO2 Battery rollout rather than a standalone project.