Finland’s Steady Energy, a startup company spun out from the VTT Technical Research Centre of Finland, and municipal energy company Kuopion Energia have signed a one-year pre-planning agreement to develop nuclear heating based on small modular reactors (SMRs) in Kuopio in Eastern Finland.
In December 2023, the two parties signed a letter of intent (LOI) that included an option for the construction of up to five district heating small modular reactors (SMRs) starting in 2030 based on Steady Energy’s LDR-50 SMR.
Under the new agreement, Kuopion Energia is now taking the next steps towards a final investment decision. The ultimate goal is to begin constructing the plant to provide district heating for Kuopio in the early 2030s. As part of the agreement, Kuopion Energia will start an environmental impact assessment for potential plant locations.
The investment decision will be made by Kuopion Energia, which will also seek necessary zoning changes in due course. Zoning decisions are the responsibility of the City of Kuopio. The estimated construction time is 3.5 years. Suitable locations for the plant will be refined during the environmental impact assessment process. Generally, suitable places in cities include existing industrial sites.
The LDR-50 has been in development at VTT since 2020. The 50 MW reactor is designed to operate at around 150 degrees Celsius and below 10 bar (145 psi). Steady Energy says its operating conditions are less demanding than those of traditional reactors, simplifying the technical solutions needed to meet the high safety standards of the nuclear industry.
The project was part of VTT LaunchPad, a science-based spin-off incubator, where VTT researchers and technology are brought together with business leaders and investors to renew industries. VTT LaunchPad supports incubator teams to develop VTT-owned intellectual property rights into fundable spin-off companies.
The LDR-50 reactor module comprises two nested pressure vessels, with their intermediate space partially filled with water. When heat removal through the primary heat exchangers is compromised, water in the intermediate space begins to boil, forming an efficient passive heat transfer route into the reactor pool. The system does not rely on electricity or any mechanical moving parts, which could fail and prevent the cooling function. The innovation was awarded a patent in 2021.
According to Steady Energy, the passive heat removal solution incorporated into the LDR-50 reactor plays a major role in its safety. Passive systems make it possible to meet extremely high safety requirements with simplified technology.
In June, Steady Energy said it planned to start construction of its SMR pilot plant in Finland next year. Potential sites include the Finnish capital Helsinki and two other cities. CEO Tommi Nyman said construction of the first operational plant is projected to begin by 2028, with the first unit expected to be operational by 2030.
The pilot investment is estimated to be around €15–20m ($16–22m). Final evaluations of potential sites are underway, with a decision expected by the end of summer. Currently, the proposed locations for the pilot plant include Salmisaari caves in Helsinki’s inner city, the Huuhanmäki caves in Kuopio, and the power plant sites at Kymijärvi and Teivaanmäki in Lahti in Southern Finland. Steady Energy previously said it had signed letters of intent for the delivery of up to 15 reactors with Helsinki’s local utility Helen and Kuopio Energy.
