Värtaverket biomass CHP plant facade with red fins and young trees.

Värtaverket biomass power plant expansion, Stockholm

Värtaverket - Expansion of a combined heat and power plant

An expansion of Sweden’s largest biomass-fired power plant, designed to fit a sensitive urban and ecological context.

Värtaverket is a combined heat and power plant in central Stockholm. The client, Fortum AB, expanded the facility to increase capacity for renewable, biomass-based energy. The site sits within an urban area with neighbors, protected oak trees, and an important wildlife passage connecting the northern and southern parts of Djurgården.

AFRY Architects contributed architectural design for the expansion, aligning a major piece of energy infrastructure with its urban and ecological setting. The work focused on reducing local impacts, integrating logistics, and ensuring the plant’s long-term adaptability.

Close-up of Värtaverket biomass CHP plant’s red vertical facade.

Logistics and landscape considerations

Sensitive surroundings shaped the project’s logistics and layout. To avoid extensive truck movements through the city and reduce disturbance, part of the facility is located underground. Biomass fuel is supplied via tunnels directly from the nearby port of Värtahamnen, limiting above-ground transport and helping protect the area’s character and biodiversity.

These measures respond to:

The presence of protected oak trees,
The need to maintain a wildlife corridor across Djurgården,
Proximity to neighbors within a dense urban context.

A facade in brick

Above-ground volumes are enclosed by a well-insulated, sound-absorbing façade to limit noise and improve environmental performance. The exterior is clad with brick elements that reference historic industrial buildings in the area, connecting the new expansion with Stockholm’s architectural heritage.

Vertical brick slats follow the configuration of the plant’s internal functions. This approach allows the technical layout to be adjusted over time without losing the building’s cohesive architectural expression. The result is a robust, homogeneous appearance that accommodates future changes in equipment and operations.

Historic brick building beside Värtaverket biomass CHP plant in Stockholm.

A resilient, adaptable facility

By combining underground logistics, careful site planning, and a flexible façade system, the expansion strengthens Värtaverket’s role in Stockholm’s energy system while respecting its location. The design supports long-term adaptability and provides a clear architectural identity for one of the country’s most significant biomass-fired energy facilities.