Press Release: European project CEEGS demonstrates breakthrough in CO₂-based energy storage

FINAL PRESS RELEASE: European project CEEGS demonstrates breakthrough in CO₂-based energy storage

Press release I Seville I October 2025

As the CEEGS project concludes this month, the consortium celebrates the successful completion of a pioneering European initiative that has proven the feasibility of using CO₂ for clean, efficient, and safe energy storage combined with geological storage at the laboratory scale.

Europe’s path to climate neutrality, as set out in the European Green Deal and the EU’s long-term climate strategy, depends on the large-scale use of renewable energy sources such as wind and solar. Yet, because these sources depend on weather conditions, effective energy storage systems are essential to ensure a stable supply. At the same time, carbon capture and storage (CCS) remains crucial to decarbonising heavy industries such as cement, steel, and fertiliser production – sectors where emissions are difficult to avoid.

The Horizon Europe-funded CEEGS project addresses both challenges through an innovative CO₂-based electrothermal and geological energy storage system. The concept integrates renewable energy storage with CO₂ capture and underground storage, turning CO₂ from a waste product into a valuable working fluid for clean energy storage and recovery. This cross-sectoral approach helps to increase the efficiency and cost-effectiveness of both renewable energy and CCS technologies – at a low environmental impact.