Third Finnish city considers using modular reactors for district heating

Finnish company Steady Energy, a developer of small modular reactors (SMRs), has signed an agreement with municipal energy company Keravan Energia to develop a nuclear reactor for heating the city of Kerava. Located in the Uusimaa region and part of the Helsinki metropolitan area, Kerava is the third Finnish city to consider using SMRs for heating. Earlier initiatives were launched in Kuopio and Helsinki.

The agreement represents the first step in assessing the feasibility of deploying SMR technology in Kerava. The next steps include assessing site suitability, licensing, land-use planning and the technical and economic viability of a nuclear heating plant tailored to Kerava’s energy needs. The city has an extensive district heating network.

"We have a strategic goal of achieving carbon neutrality by 2030," said Keravan Energia CEO Jussi Lehto. "To achieve this, we need to minimise our emissions as affordably as possible and ensure secure energy supplies under all circumstances."

If the project proceeds to the investment phase, construction of the SMR could begin as early as 2029, with district heating operations expected to start in 2032.

Steady Energy’s technology and its advantages

Steady Energy has been developing its LDR-50 small modular reactor at VTT Technical Research Centre of Finland since 2020. The reactor has a thermal output of 50 MW, a coolant outlet temperature of around 150 °C and a pressure of up to 1 MPa. The company says its operating parameters are lower than those of conventional reactors, simplifying the technical solutions required to meet the nuclear industry’s high safety standards.

Steady Energy estimates that the LDR-50 could be deployed within seven years, including licensing. Expected construction costs are approximately 100 million EUR (around 2.5 billion CZK), making it an affordable solution for municipal energy companies.

"Heating water to 150 °C accounts for 10% of global emissions," said Steady Energy CEO Tommi Nyman. "Our reactor is designed specifically for this purpose, which could make it the simplest commercial nuclear reactor in the world. This design ensures that the cost of heat produced by the LDR-50 is competitive with other alternatives."

Finland as a leader in clean heating

Nyman added: "The climate crisis will not abate until we start using clean sources to heat our homes. More than 80% of energy worldwide still comes from fossil sources, and almost half of that energy is used for heating and cooling. Finnish energy companies are leading the drive to move entirely away from energy based on combustion."

In December 2023, Steady Energy signed a memorandum of understanding with municipal energy company Kuopion Energia in eastern Finland. The memorandum includes the possibility of building up to five district heating reactors, with operations planned to begin in 2030. The agreement followed a memorandum signed in October between Steady Energy and Helsinki energy company Helen, which envisages building up to 10 SMRs for district heating.

Pilot project in 2025

Next year, Steady Energy will begin building a pilot heating plant in Finland to demonstrate the facility’s functionality and the company’s ability to deliver this complex project with its extensive supply chains. The main difference between the experimental and full-scale heating plants is that the water will be heated with electricity rather than a nuclear reactor. Helsinki, Kuopio, Espoo and Lahti are among the potential locations for the facility.