Photos © Ivar Kvaal
Snøhetta, alongside collaborators R8 Property, Skanska, and Asplan Viak, has completed its fourth energy-positive building in its powerhouse portfolio.
As part of the Powerhouse series, Powerhouse Telemark, Norway, sets a new standard for the construction of environmentally sustainable buildings by reducing its yearly net energy consumption by 70 percent when compared to similar new-construction offices, and by producing more energy than it will consume over its entire lifespan. Through standardized interior solutions and co-working spaces, tenants can scale their office spaces as needed, granting much needed flexibility in a global context where remote working solutions continue to increase in demand.
Situated in the historic industrial city of Porsgrunn in the county of Vestfold and Telemark, the new 11-story building marks a symbolic continuation of the district’s history as Telemark is home to a 19th-Century hydropower plant. Powerhouse Telemark indicates the area’s growing investment in the green economy. The south-east facing façade and roof of Powerhouse Telemark will generate 256,000 kWh each year, approximately 20 times the annual energy use of an average Norwegian household, and surplus energy will be sold back to the energy grid.
The skewed and slightly conical building features a clearly defined 45-degree tilting notch on the east-facing façade, giving it a clearly identifiable expression that stands out in the industrial context of the surrounding Herøya industry park. Inside, the building features a barception, office space, including two stories of co-working spaces, a shared staff restaurant, penthouse meeting spaces, and a roof terrace overlooking the fjord. Two large staircases connect the building’s ground and top floors, from the reception area and all the way up to the staff restaurant and penthouse meeting rooms. A wooden staircase reveals itself at the ninth floor, visually tying the staff canteen and penthouse meeting room area together and leading visitors to the building’s roof terrace.
Powerhouse Telemark has also obtained the Building Research Establishment Environmental Assessment Method (BREEAM) Excellent certification.
An energy producing façade and roof
The building’s striking 24–degree tilted roof gently slopes to surpass the extremities of the building’s volume, expanding the roof’s surface and ensuring a maximum amount of solar energy can be harvested both from the photovoltaic (PV) canopy and the building’s PV-cell clad south-facing façade.
To the west, north-west, and north-east the building is clad with wooden balusters providing natural shading on the most sun-exposed façade. Behind the wooden balusters the building is covered with fiber cement façade panels that give the building a unified expression. Functioning just as a passive house, the building is super insulated and features triple isolated windows throughout. The concrete slabs lend the building a density akin to that of a stone structure storing thermal heat during the day and slowly emitting heat during the evening. A low ex system with water loops in the border zones of each floor, assures the building is efficiently cooled and heated through geothermal wells dug 350 m (1148 ft) below ground.
Powerhouse Telemark also utilizes a series of low-tech solutions to ensure tenant comfort is prioritized, allowing the office building to be used to its full potential. The building’s gently skewed west- and southeast-facing façades allow for a maximum of daylight and shading while also generating views and flexible indoor spaces. To the northeast, the building is leveled to accommodate more traditional workspaces with enclosed offices. Throughout the building, small, secluded spaces are strategically moved away from sun-exposed façades to reduce the need for cooling while also assuring that these spaces keep a comfortable temperature.
