Ultra-low energy consumption

Full-scale air-tightness testing of the facades indicates that it will be possible to get down to a net energy need of 110 kWh per sq m per year and a supplied energy need of 87 kWh per sq m per year. This is one of the results of the process we have adopted using involvement engineering and involvement planning. The involvement approach has yielded a large number of energy-smart solutions that were not described in the initial plans.

The contract specifies a target of energy needs of 150 kWh per sq m per year in the operating phase. This is roughly half the energy consumption of an average office building in Norway and approx. 10 per cent lower than the requirements specified in the new Norwegian building code TEK 07. Average energy consumption in modern office buildings is approx. 288 kWh per sq m per year.

List of possible measures
“We do what we call energy-smart building in the form of commercial measures using involvement planning. By investing another five to seven per cent of the contract amount in energy-conservation measures we have got down to the calculated figures. Various pressure tests on the building in practice have further indicated that we are well on the way to achieving our energy targets,” explains the project manager for the eco-friendly building, Torgeir Wiig.

The whole organisation and all the parties involved maintain a constant focus on energy. The link between the involvement process and energy conservation has resulted in a list of measures that have been implemented. Among the most important measures are use of heat-pump recycling, super-insulating glass, U values in the structures in accordance with the values specified in the TEK 07 building code, needs-oriented control of heating, ventilation and lighting with daylight control, natural ventilation, free cooling of concrete surfaces, harnessing condenser heat from servers and computers, low-energy lighting equipment, exposed concrete ceilings, and highly efficient heat recycling. In addition, an extensive energy-measuring programme has been implemented with 60 energy meters that continuously monitor energy consumption to ensure the building is run in the most efficient way possible.

Energy conservation in the building phase
Involvement planning has also yielded savings in Veidekke’s energy use in the building phase. “For example, by using low-energy lighting we have saved 225,000 kWh or NOK 170,000 kroner as well as reducing maintenance needs. The fact that the building is airtight and well-insulated combined with the use of district heating to heat an airtight building has meant huge savings on heating costs too,” says Torgeir Wiig.

As part of the involvement planning process, improvement groups were established for wood and concrete. Within the area of wood, specialist focus groups have been established to work on wind-proofing, window installation and construction of outside walls. The craftsmen and foremen collaborated on devising checklists to make sure that the interests of health, safety and the environment as well as cost and quality were always taken into account.