Harnessing heat from the air for homes – Salmisaari’s industrial-scale air-to-water heat pump begins production
The new industrial-scale air-to-water heat pump at Salmisaari has commenced operations. This facility, which captures heat from the outdoor air, is estimated to produce around 60 gigawatt-hours of renewable district heating and 10 gigawatt-hours of district cooling annually. The new heat pumps, which operate using emission-free electricity, mean cleaner energy and more reliable heating for Helsinki’s residents and businesses.
Helen’s district heating production is becoming increasingly electrified and cleaner. The Salmisaari air-to-water heat pump plant is one of Finland’s first industrial-scale air-to-water heat pump facilities. It increases Helsinki’s district heating capacity by about 14 megawatts and its district cooling capacity by about eight megawatts. Using the facility for cooling also enhances its energy efficiency and reduces the need for separate cooling production across the city.
Industrial-scale air-to-water heat pumps are a new technology under Finnish conditions. The heat pumps extract heat from the outdoor air and transfer it to Helsinki’s district heating network. They operate on electricity generated without emissions. These systems can produce heat even from outdoor air as cold as -8°C, making them ideally suited to Finland’s variable weather conditions.
“Helen’s district heating network, which is over 1,400 kilometres long, enables the utilisation of various production methods, and the new air-to-water heat pump plant can be flexibly integrated into it. The heat plant increases energy self-sufficiency and helps ensure that customers receive district heating at a competitive, stable price. In addition, the heat produced by the Salmisaari plant will help further reduce carbon dioxide emissions from district heating,” explains Juhani Aaltonen, Head of Sustainable Energy Solutions at Helen.
Helen continues its determined efforts towards cleaner energy production. This heating season, Helsinki will be heated for the first time entirely without coal. A new heat pump plant is currently being completed in Eiranranta and is expected to be commissioned at the beginning of 2026. Similarly, a new heat production complex is being built in Patola, and Europe’s largest electric boiler plant is under construction in Hanasaari. These projects will improve security of supply and stabilise district heating prices, ensuring sufficient heat supply even when outdoor temperatures drop well below freezing.