Helsinki gets small nuclear reactor test site

7/05/2025, 09:45

Image courtesy of Steady Energy

An abandoned coal power plant in Salmisaari, Helsinki will host Finland’s first small modular reactor (SMR) testing facility. The full-scale reactor model built by Steady Energy will not contain nuclear fuel, but will instead use electric heaters to heat water.

Dan Görgü

Construction will begin in late 2025 with a project budget of 15-20 million euros. The facility will be housed entirely inside a turbine hall rented from Helen, and will not alter the appearance of the building. The rental agreement extends until 2028.

“The main goal of the testing facility is to demonstrate the functionality of the safety systems at full scale,” explains project manager Antti Teräsvirta. The equipment will produce around 6 megawatts of power, equivalent to one-tenth of an actual reactor’s output.

This marks the first time a reactor module will undergo full-scale testing prior to actual construction. According to CEO Tommi Nyman, thorough testing before the commercial phase minimizes cost and schedule risks.

Earlier this spring, Helen ceased coal burning at Salmisaari, reducing Helsinki’s carbon dioxide emissions by about 30 percent. The company aims for carbon neutrality by 2030 and completely combustion-free energy production by 2040.

In the future, commercial small modular reactors are intended to be built underground, minimizing their impact on the urban landscape. The testing facility will also provide Helen with around 6 megawatts of emission-free additional capacity to its power grid.

The translation was written by an AI system, though the original text was authored by a human. Read the original article here