The planning of the world’s largest seasonal heat storage is well under way
YIT, Vantaa Energy and AFRY are planning the construction of the world’s largest seasonal heat storage using the alliance model. At one million cubic metres in size, the underground seasonal heat storage will have a total capacity that corresponds to the annual heating demand of a medium-sized Finnish city. The seasonal storage will play an important role in the phasing out of fossil fuels in energy production in the Vantaa region by 2026. It also supports the goal of carbon neutrality by 2030. The seasonal heat storage containing 140 °C water will be used to store renewable energy