Europe’s largest electric boiler plant nears completion in Helsinki

Europe’s largest electric boiler facility is being built in Helsinki to heat the city, with the capacity to produce nearly 10 percent of the capital’s district heating demand during peak winter cold—provided electricity prices remain favourable, reports Finnish broadcaster Yle.

The plant, located in the Sörnäinen district, will house four large electric boilers, the last of which was installed this week. Once fully operational by the end of the year, energy company Helen will have 570 megawatts of electric boiler capacity at its disposal.

Timo Aaltonen, Helen’s director responsible for electricity and heat, described the scale of the project as unexpected. “Years ago, when electricity was more expensive in Finland, no one would have believed we’d be producing heat with electricity on this scale,” he said.

How electric boilers work

The boilers function like massive electric kettles, converting electricity into heat using simple resistance elements. While their energy efficiency is low—producing heat equal only to the electricity consumed—Helen argues they offer critical flexibility. Unlike heat pumps, which require specific conditions to operate efficiently, electric boilers can be deployed instantly when needed.

The shift to electric heating is driven by emissions reduction goals but also enhances energy security. Aaltonen noted that Helsinki’s diverse district heating system allows rapid adjustments, unlike gas-dependent regions in Central Europe. “If we relied solely on gas, the challenges would be on a completely different scale,” he said.

Cheap electricity despite high spot prices

The project benefits from policy changes that have made fossil fuels more expensive through emissions trading, while wind power expansion—supported by subsidies and technological advances—has driven down electricity costs during favourable conditions.

Last winter, despite record-high spot prices during cold snaps, Helen occasionally secured cheap electricity for its boilers through intraday markets, where prices fluctuate based on real-time supply and demand. “Even if we hadn’t bought from the spot market, intraday trading made it profitable to replace fossil fuels with electricity,” Aaltonen explained.

Costs shared nationwide

While electric boilers are relatively inexpensive to build compared to facilities like the Vuosaari bio-heating plant, their operation relies on a new €200 million high-voltage cable being laid to Helsinki. The cost will be split: grid operator Fingrid’s share will be covered by electricity service fees paid by all Finns, while Helen’s portion will be passed on to Helsinki’s electricity consumers.