Spearheading electricity-based heating on a large scale
District heating is a local system for cities that transfers energy in heated water from energy sources to heat users in a network of underground pipes. It is the only way to recycle heat energy from numerous different and distributed sources to thousands of buildings under one optimized infrastructure. The heat is typically used to warm buildings and tap water.
In Finland, Fortum is showcasing a next generation district heating system extending across the cities of Espoo, Kauniainen and Kirkkonummi. Operating since 1954, the 900-kilometre-long system is currently undergoing a major transformation to replace fossil fuels with smart and flexible solutions that are largely based on renewable or nuclear power: waste heat utilization, heat pumps, heat accumulators and electric boilers. Approximately 40 percent of the district heating demand will be met by recycling waste heat from Microsoft's new datacenters.
Artificial intelligence optimizes the operations of the entire system. The solutions are modular and can be tailored according to local heat sources, be it waste heat, air, or something else.
Fortum and the City of Espoo have committed to this transformation that will contribute to Espoo's carbon-neutrality target by 2030. The use of coal was discontinued in 2024, over a year ahead of schedule. This programme, called Espoo Clean Heat, provides a flagship example of decarbonization by electricity-based heating and a transition to local energy production on a large scale.
Examples of transformation projects
2020's (est): Recycling waste heat from Microsoft's data centre region
A growing number of data centers is needed to accommodate the increasing global digitalization. It makes sense to locate big data centers near cities where waste heat from servers can be recycled to district heating networks. In Finland, Microsoft's two large data centers will provide 40% of the consumed heat in the network area.
2023: Ireland's first waste heat -based district heating network
Ireland's first-of-its-kind district heating network is in operation in Tallaght, South Dublin. It recycles waste heat from the Amazon Web Services datacentre to public buildings and, in the future, also to apartments. The network is owned by Ireland’s first publicly owned, not-for-profit energy company, trading as Heatworks.
2023: Industrial-scale air-to-water heat pumps
The technology that is used in air-to-water heat pumps at homes has been developed to an industrial scale in our pioneering projects. Our air-to-water heat pump plant produces a notable share of the Espoo area's district heating, complementing the versatile assets in the region. It also creates cooling for local needs.
2021: A third heat pump unit to recover heat from waste water
A 25-megawatt unit, the largest in Finland, was built in the Suomenoja, Espoo heat pump plant in 2021. All three units recovers excess heat from treated wastewater, as well as from seawater in the summer. The plant covers approximately of the demand in the district heating network area.
2020: A bio-heating facility in Kivenlahti
A biomass-fired 49-megawatt heating plant was commissioned in 2020 on the Kivenlahti, Espoo site where two wood pellet boilers were already producing district heat. The new facility replaced one of the last two remaining coal-fired units in the Suomenoja power plant.
2022: AI-driven smart steering to reduce emissions
Demand side response (DSR), or smart control of district heating, optimises both the heat production and the heating of buildings at differing intervals so that heat can be allocated to where it is most needed at a given time. With demand side response, the use of back-up heat plants can be reduced, resulting in less fossil fuel use.
The transformation to electricity-based heating
District heating is a reliable and convenient heating method - This is how over 50% of the Finns think
50%
District heating is the most popular heating method in Finland - almost 60% of the new building space is heated by district heat
60%