10.12.2009
Minimal energy consumption at new low-cost pier

Copenhagen Airport sets new standards for energy efficiency in an airport building with its planned low-cost pier, CPH SWIFT. Ground water cooling and solar panels together with optimal control of ventilation and lighting ensure a very low level of energy consumption for the new building scheduled to be opened in 2010.

When CPH SWIFT, Copenhagen Airport’s new facility for low-cost traffic, is ready for use towards the end of 2010, it will be a building that sets new standards for energy efficiency in an airport building.

With a level of energy consumption of max 50 kilowatt hours per square metre per year, CPH SWIFT will correspond to a building in low energy class 1, the best energy class, for which energy consumption is only half that of traditional new buildings.

“We have focused on energy efficiency ever since we started on the CPH SWIF T project and have studied various options for reducing the building’s energy consumption. By means of forward-looking solutions such as groundwater cooling and solar panels, we have managed to design a building with very low energy consumption without compromising our demands for quality and functionality,” said Kristian Kongstad, VP, Real Estate, Copenhagen Airports.

CPH SWIFT cannot formally be classified as a low-energy class 1 building as the low-cost pier, which will be an integral part of the international airport, will be in operation round the clock. That means the 9,100 square metre building will have higher total energy consumption than buildings such as office buildings with similar energy efficiency. But compared with a traditional airport building, energy consumption in the low-cost pier will be very low.

Groundwater replacing freon
The main reason for the low energy consumption is the installation of a brand new groundwater cooling system at Copenhagen Airport. This system will not only meet the requirements for comfort cooling in the new low-cost pier, but also in the airport terminals, where groundwater cooling will gradually replace the freon-based cooling systems which currently provide comfort cooling.

Conventional comfort cooling involves high energy consumption, and Copenhagen Airport uses a total of four million kilowatt hours per year for cooling the passenger areas and offices, equivalent to one tenth of its total energy consumption. This consumption can be reduced by as much as 80% with a fully developed groundwater cooling system, which will reduce the airports’ annual CO2 emissions by about 1,500 tonnes.

Heating also comes from the underground
The groundwater system, which does not use drinking water but saline groundwater, will not be used for cooling alone. In popular terms, the system will be used during the winter in the following way: the groundwater that was used for cooling during the summer period will be pumped up again and used for heating in combination with heat pumps. Therefore, it will not be necessary to install district heating in CPH SWIFT.

The installation of the new groundwater cooling and heating system started recently after completion of test drillings and analyses which have shown that the groundwater in the area is suitable for the purpose.

Solar panels on the roof
Installation of solar panels is another energy-saving initiative in CPH SWIFT, where it is expected that a 500 square metre solar cell system will be installed on the roof of the hallway connecting the new building with the airport’s existing Pier D. The solar cell system will have the capacity to supply approximately 55,000 kilowatt hours of power per year.

In addition to groundwater and solar panels, the new building will achieve its high energy efficiency through intelligent control of ventilation and lighting, good insulation and large window areas that provide lots of daylight concurrently with a low penetration of heating from the sun, so that the need for cooling is reduced.

“Climate considerations and energy savings play an ever greater role in the way we operate our business, and with CPH SWIFT we have been able to include energy considerations in our planning right from the early stages of the project. The low energy consumption harmonises well with the philosophy behind the low-cost pier, for which the focus is specifically on efficiency and low costs,” said Kongstad.

Facts: This is how groundwater cooling works: The process of groundwater cooling is very simple: Cold groundwater is pumped up from storage chambers in the underground, and the cold groundwater is exchanged with “ordinary water”, before the groundwater is led back to another groundwater chamber. The cooled “ordinary water” is piped to the buildings, where it is used to cool the air in the ventilation systems which can therefore blow cool air into the buildings. In the winter, the direction of the water is reversed so that the now partially heated groundwater is pumped up again after which the heat from the water is  increased to 40 degrees centigrade by means of a heat pump before it is exchanged again and the cooled water is sent back into the underground

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