"Passive" office building in Aarhus completed
From 2019 onwards, all new public buildings in the EU will have to be near zero-energy buildings. The practical implications of this energy standard can be seen in Aarhus, Denmark: A recently completed new office building for the city administration, designed by C. F. Møller Architects, not only complies with the passive house standard but also uses solar energy to cater for its heating, cooling and electricity requirements.
The office building is located in a development zone of the Port of Aarhus. It is an extension of the Technical Administration of Aarhus Municipality, and for the client, the aim was to create an example of progressive office building construction, with energy consumption at 'passive house' level and a good indoor climate. The building is in energy class 1, further enhanced with elements drawn from the German passive house standard.
A 200 m slatted wall of solar panels and a 170 m2 solar wall provide distinctive, sculptural elements in the facade. The wall of solar panels, which is slightly tilted in relation to the rest of the facade, produces electricity for the building. The 170 m2 solar wall comprises a vertical element in the building's corner conclusion, extending over all storeys of the building. The solar wall collects energy which it uses to warm up the ventilation air to the offices in winter and to cool the offices in summer.
The office building has a large, south-facing facade and thus receives plenty of sunlight, say the architects. To provide shade from the sun, the windows are recessed and are equipped with shade panels. These are clad with solar cells, and thus also produce electricity for the offices. Energy-friendly materials and elements with ultra-low thermal conductivity have been used throughout, such as vacuum-insulated windows.
The office building, which has a facade of natural stone, is six storeys tall with a loft storey for technical installations. It has a total heat consumption of a maximum of 15 kWh/m2/year. The overall energy consumption is estimated to be at most 50 kWh/m2/year. The building is twice as airtight in its design as required by the Danish building regulations.