Finnish start-up Steady Energy is to co-operate with South Korea’s largest district heating provider, Korea District Heating Corp on heat-only small modular reactors (SMRs).
“Under the brand slogan Better World with Clean Energy, we will collaborate with Steady Energy to provide carbon-free heat and lead the way in stabilising the national energy grid and achieving carbon neutrality”, said Korea District Heating Corp President & CEO Jeong Yong-ki.
Steady Energy, spun out of the VTT Technical Research Centre of Finland in 2023, is developing the LDR-50 SMR. It is designed to only produce heat and is focused on district heating, as well as industrial steam production and desalination projects.
The 50 MWt LDR-50, which has been under development at VTT since 2020, is a simplified pressurised light water reactor specifically designed to operate at around 150°C and below 10 bar (145 psi). The reactor module comprises two nested pressure vessels, with their intermediate space partially filled with water. The system does not rely on electricity or any mechanical moving parts, which could fail and prevent the cooling function. It was awarded a patent in 2021.
The LDR-50 reactor design is being assessed by the Finnish Radiation and Nuclear Safety Authority (STUK – Säteilyturvakeskus). The aim is for construction of the first plant to begin in 2029. Steady Energy has already signed agreements for 15 reactors in Finland and in December 2024 signed a contract with Belgian engineering firm Tractebel to provide engineering services.
“The 10m-strong Seoul metropolitan area is keeping a sharp eye on Helsinki’s progress in adopting small nuclear,” said Steady Energy CEO Tommi Nyman. “Many are particularly interested in the fact that our facility is built underground, which makes clean heat practical in dense cities. It turns out that many of the hurdles in decarbonising urban heating stem from plant size. Finland is closely followed as the first country with proven final disposal while South Korea has superb nuclear operating expertise and supply chains.”
In July, Steady Energy completed a €32m ($37.7m) funding round, most of which will go towards a pilot plant to be constructed at a recently decommissioned coal plant in Helsinki city centre. The pilot plant will not contain nuclear fuel. Instead, water within the reactor loop will be heated by electrical resistance elements providing approximately one-tenth of the LDR-50 reactor power output. It will physically demonstrate the LDR-50 reactor’s key safety features. It will give detailed advance insight into steps required for the eventual commercial plant. Steady Energy aims to reach ready-to-build phase by 2028.
