Daniels Family Sustainable Energy Foundation
POWERHOUSE KJØRBO
A cutting-edge new building in Norway leads the way in sustainability and reducing energy consumption in living spaces
By Synnøve Marie Kvam Strømsvåg
Powerhouse Kjørbo looks ordinary. From outside and inside it looks like your average modern office building. But Powerhouse is not average and not ordinary.
It is a power-saving, power-creating, sustainable environment that sets the standard in the refurbishment of existing office buildings, as well as new constructions. Its principles are not complicated, yet brilliantly applied.
Powerhouse Kjørbo, Sandvika, Norway
The Powerhouse concept uses known technology in innovative ways, and in doing so an existing ordinary office building when refurbished according to the Powerhouse model can produce more renewable energy than it consumes in its lifetime. The pilot for this project is Powerhouse Kjørbo, headquarters of Norwegian engineering consultancy company Asplan Viak, who are part of the Powerhouse alliance. Powerhouse is a collaboration of companies dedicated to creating energy positive buildings, and consists of real estate company Entra Eiendom, entrepreneurs Skanska, architects Snøhetta, the environmental ngo ZERO, the aluminium company Sapa og Asplan Viak. Powerhouse Kjørbo has been operational since 2014, and since then several other Powerhouses have come into existence or are under construction.
No comforts has been sacrificed in this process; walking through the hallways on a warm summer or a cold winter day, the temperature and indoor environment is comfortable and stable. In fact, the tenants report of better indoor climate, better acoustics, better lighting and more comfortable temperature than before the refurbishment. Reports conclude that not only is the environmental ambitions more than fulfilled, the financial savings are also significant.
Staircase inside the Powerhouse building
No comfort has been sacrificed in this process; walking through the hallways on a warm summer or a cold winter day, the temperature and indoor environment is comfortable and stable. In fact, the tenants report of better indoor climate, better acoustics, better lighting and more comfortable temperature than before the refurbishment. Reports conclude that not only is the environmental ambitions more than fulfilled, the financial savings are also significant.
The refurbishment of these existing office buildings to modern energy standards led to a reduction in energy consumption by over 86 percent. Keeping in mind that in Norway, buildings account for about 40 per cent of domestic energy consumption, and half of that is for heating, the Powerhouse principles are an efficient way of saving energy. Efficient insulation, ventilation and lighting are the most impactful measures. The energy is sourced from one of Norway´s largest solar panel parks, located on the roof, and also cooled in summer and heated in winter by Ground Source Heat systems. Only a few meters below the surface, earth is at a reasonably constant temperature. In Southern Norway this is approximately 7-8 degrees Celsius. Taking advantage of this, the Ground Source Heat Pump and cooling systems pump a water-alcohol mixture through a piping system, a «loop» or energy wells drilled into the ground. By exchanging heat between the ground, the heat pumps and the building this system provides heating in winter and also hot water. The «free-cooling» process provides cooling by pumping the water-alcohol mixture directly into the ventilation system.
In the building's lifespan, energy consumption calculation covers every aspect of construction: the production and transportation of building materials, the construction process itself, as well as maintaining and running the buildings. Windows from the original buildings, not meeting modern energy standards, have been recycled into indoor glass walls. A winding staircase acts as a natural ventilation shaft with no moving parts, and also makes for a pleasant architectural element.
Ceramic coffee and tea mugs used to reduce waste, hanging after being used and washed
The local council required that the facade should remain similar-looking to the original buildings, with a dark or black finish. The result is another testimony to the Powerhouse alliance´s ability to apply known technology in innovative ways. Wood is low-maintenance if treated right initially, and a popular building material in Norway. In regular Norwegian buildings one would traditionally paint these to protect it from weathering and get the desired colour. However, to maintain the environmental aspect running through the core of the entire concept as well as satisfy the local council, local short-travelled wood was chosen, and treated with the traditional Japanese technique shou sugi ban. This technique, through charring the surface of the wood, protects it from fungi and other harmful organisms. In Norway, charring has traditionally been used as a technique in quai constructions, but not for building facades.
Due to the environmental standards of the Powerhouse concept, using gas in the charring process was out of the question, and the local supplier developed a construction where the panels were pulled over a fire made up of left-over wood from the supplier's production of wooden floors.
The concept of Powerhouse goes beyond energy saving. These buildings now produce excess clean energy which it sells back to the grid. The energy saved and stored from efficient use serves other buildings outside the Powerhouse, and fuels the nearby Uno-X hydrogen fuel station. Powerhouse Kjørbo now holds the BREEAM-NOR classification «Outstanding as built», the highest level of energy classification.
In a country where modern businesses pride themselves on inhabiting energy positive buildings as part of their environmentally responsible values and profile, this concept has been a success and many more Powerhouses have been built or are about to be. But it is not necessary to sacrifice financial returns in exchange for environmentally responsible energy consumption. The energy saved and used efficiently also represents financial savings for the tenants of these buildings, and thus should be of interest to all modern companies.
Powerhouse Kjørbo has received much national and international attention, has been nominated for a number of awards, attract interested parties from all over the world, and has become a flagship. It clearly demonstrates that existing properties can be renovated to not only meet, but exceed, modern energy consumption standards even in cold climates, and that it is of commercial and environmental benefit to all parties involved.