By 2035, Finland’s capital city aims to be carbon-neutral. To achieve this goal, an 80 per cent reduction in municipal greenhouse gas emissions will be paired with efforts to reduce emissions beyond the city’s boundaries offsetting the remaining 20 per cent. It’s no small feat — and the built environment plays a major role. According to the city’s carbon-neutral Action plan, “The most significant sources of greenhouse gas emissions in Helsinki are the heating of buildings, electricity consumption and traffic.” In the coastal Vuosaari neighbourhood, however, a new building reverses the trend, converting excess heat from a neighbouring power plant — as well as seawater heat from the nearby Baltic Sea — into a carbon-free district energy hub.

Designed by local firm Virkkunen & Co Architects Ltd., the Vuosaari Heat Pump Building sits alongside a pair of buildings that make up a major local power plant, both of which were also designed by Virkkunen & Co and completed in the 1980s and 90s respectively.

And while the new two-storey structure echoes the simple yet tastefully articulated brick frontages of its industrial neighbours, it serves a distinctly novel purpose. Inside, a heat pump harnesses the excess heat of the internal cooling water circulation of the existing power plant in the winter, while using the seawater heat for the other half of the year.

Situated on a prominently visible site near the existing power plant’s main entrance, the narrow building features two long frontages clad with mottled red brick. Arranged with an articulated stack-bond grid across the upper level, the texture introduces a subtle flair. Meanwhile, a double-skin façade announces the main entrance, with transparent curtain wall glazing — which invites passersby to look inside — paired with a metal screen of white-painted steel across the upper level, which protects the interior from excess glare and solar heat gain.

The Vuosaari Heat Pump interior includes a double-height main process equipment space on the ground floor, as well as electrical and control rooms. A machine room occupies the smaller second floor, exiting out onto an external staircase at the back of the building, which leads up to the roof. Like the more prominent glass frontage, the pared down rear façade features an angled metal screen, which is paired with a simple, functional service wall of prefabricated concrete blocks. It’s a humble kit of parts for a revolution in the making.