Energy storage based on CO2 battery technology

EPV is planning to construct an energy storage system based on CO2 battery technology in Jokiperä, Laihia. The planned energy storage system will consist of up to 8 units, enabling a total storage capacity of approximately 1,600 megawatt-hours.

The energy storage system is a facility where energy is stored through the phase change of carbon dioxide. The liquefaction of carbon dioxide requires energy, and vaporization back to gas releases energy. The heat required for re-vaporization is stored during the liquefaction of carbon dioxide, so no external heat source is needed for vaporization. The energy storage system will be connected to the power grid and will support the balance of the transmission network. It will be possible to feed and store electricity in the storage system at a very fast cycle, achieving longer-term and higher-capacity storage capability compared to traditional battery storage systems.

With the clean transition, the share of renewable energy in the power grid is increasing significantly. At the same time, fossil-based, combustion-based capacity is decreasing, making it more challenging to maintain balancing capability. However, the power grid must be supplied with an amount of energy corresponding to consumption to maintain balance. When too much electricity is produced, charging the energy storage system acts as a consumption point, and when the grid situation requires, it acts as a production facility. The CO2 storage system can convert the inductive electrical energy produced by renewable energy into inertia-containing electrical energy, improving the power system’s ability to resist frequency changes. This provides a balancing energy solution for the grid.

The implementer and user of the energy storage system would be EPV Energia Oy, whose owners are domestic, municipal energy companies. The main equipment supplier for the project would be Energy Dome S.p.A. from Italy.

The project is in the preliminary planning phase and is applying for EU Innovation Fund funding. The goal is to make an investment decision during 2026, subject to the confirmation of possible support decisions.

Read the environmental impact assessment conducted for the project (in Finnish). The results of the environmental impact assessment will be taken into account in the further planning of the project.

For more information: Emma Lonka, Development Manager at EPV Energia, 010 5055 087