This article appeared in the March 2020 issue of ARCHITECT.
Over the last 20 years, the northeast Helsinki neighborhood of Kalasatama has transformed from a raw industrial zone to a hip—if still gritty—urban cultural hub. It’s also the centerpiece of the city’s various “smart” initiatives, including hundreds of internet of things sensors and subsidies for high-tech startups. Currently home to just 2,000 people, Kalasatama is expected to add another 20,000, along with 8,000 jobs, over the next decade.
All that growth has put new demands on the local power grid—as has the city’s plan to shift away from fossil fuels completely by 2030. And so, about 10 years ago, Helsinki decided to build a new electrical substation on Kalasatama’s western edge.
Power-grid infrastructure rarely gets the architectural imagination firing. But Virkkunen & Co Architects, the local firm hired by the city power company to design the substation, has decades of experience with precisely this sort of project, as well as with bringing highly contextual, subtly expressive designs to an otherwise mundane typology. While the substation is a completely new structure, by coincidence it sits between two historic power-generation facilities: The former Suvilahti power plant, which was recently converted into a cultural center, and the Hanasaari plant, a still-functioning coal-fired cogeneration facility from the 1970s.
The Suvilahti facility, built in 1909, was the first in Finland to be made of steel-reinforced, in situ concrete—which was as uncommon a choice for the region then as it is today, says Tuomas Kivinen, the lead architect on the project for Virkkunen. In situ concrete can be unpredictable, especially in Helsinki’s far-northern climate. But as a nod to that history, the firm decided to pour the exterior structures of all three of the substation’s buildings—two for transformers and a third for switchgears—on-site, adding titanium oxide to the mix to give the concrete an off-white, weathered look.
For the façade, the firm had to reconcile two competing demands: The city government insisted that the buildings maximize their engagement with the heavy pedestrian and automobile traffic around its edges by sitting as close to the edge of the site as possible while the client insisted that, for security reasons, the buildings sit back from the perimeter.
Virkkunen’s solution was to set the buildings back from the perimeter by about 41/2 feet, and to drape them in a woven stainless steel mesh on a fixed armature that brings the texture of the walls flush with the fence running around the site. “The double façade meets both these requirements,” Kivinen says. It also adds an unexpected beauty to the site, he says: The mesh catches the sun at different angles during the day, and casts decorative shadows on the concrete walls behind, giving it a colorful, ever-shifting effervescence.
The architects also had to grapple with the site itself. Though it had long sat fallow, in 2009, the city of Helsinki erected a temporary fence on the site to provide a spot for graffiti artists—a popular and widely respected artistic endeavor in Helsinki. To keep that spirit intact, the firm designed the 3-meter-high (nearly 10-foot-high) perimeter fence with hollow, anodized, interlocking aluminum profiles that invite graffiti artists to paint a constantly evolving façade around the substation. “It’s been extremely popular,” Kivinen says, noting that it softens the industrial look of the site without taking away from the neighborhood character.
As part of Helsinki’s pledge to move away from fossil fuels, the nearby Hanasaari power plant will be decommissioned by 2024, making the new substation, and its state-of-the-art energy-management technology, all the more important, Kivinen says. “Decommissioning these old plants places more demand on the network to react in a smart way, and this substation is part of that.”
Project: Kalasatama Electricity Substation and Suvilahti Graffiti Fence, Helsinki, Finland
Client: Helen Electricity Network
Architect: Virkkunen & Co Architects, Helsinki . Tuomas Kivinen (lead architect); Tomi Laine, Uros Kostic, Anna Blomqvist, Maija Toivola (design team)
Structural Engineer: Sweco
ME Engineer: Granlund
Construction Manager: Helen Electricity Network
General Contractor: Oy Rakennuspartio
Size: 898 square meters (9,666 square feet)