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Cavern Thermal Energy Storage

Presentation of the project

We are planning to build a cavern thermal energy storage in Kuusikonmäki in Vantaa. The building of the storage facility plays a key role in moving towards fossil-free production in Vantaa.

With a size of one million cubic metres, the facility will be the largest cavern thermal energy storage facility in the world. Its capacity is 90 gigawatt-hours, corresponding to the annual heat consumption of an average-sized town in Finland.

Renewable energy from e.g. solar, wind and geothermal sources will be stored in the storage facility. It will also enable storage of waste heat, which is produced, for example, in data centres. The stored energy replaces natural gas use in the winter season, thus reducing carbon dioxide emissions by 65,000 tonnes a year.

The cavern thermal energy storage promotes several climate and energy targets of the EU: improving resource efficiency by utilising waste heat, increasing the share of renewable energy forms, and integrating various energy systems.

Environmental impacts of the project are assessed

The EIA procedure for the project was launched in winter 2020, and the EIA programme was available for viewing in April 2021. This environmental impact assessment programme presents the information about the project and its alternatives, the planning schedule, a plan about the environmental impacts that are studied in connection with this procedure and how the studies are conducted, as well as a plan for organising participation and communication. The environmental impact assessment is currently underway. The objective is to publish the EIA report in October 2021. The environmental impact assessment is carried out by AFRY Finland Oy as consultancy work. The Centre for Economic Development, Transport and the Environment for Uusimaa acts as the liaison authority in the EIA procedure.

Further information about the EIA procedure of the project (In Finnish)

Town planning related to the project

The City of Vantaa has launched the town planning process related to the project. The participation and assessment scheme for town planning is now publicly displayed, and opinions on it can be submitted by 20 May 2021.

Further information about the town planning of the project (In Finnish)

Timetable for the implementation of the project

The project is in the preliminary planning stage. According to an indicative timetable, the project construction would take place in 2022–2026.