It is important for Oslo Airport to protect the environment and be as environmentally friendly as an airport can be. We have therefore taken a number of steps to reduce our carbon footprint while we expand.

Wooden roof and passive standard

We use a high percentage of recycled materials, greenhouse gas friendly insulation and concrete where part of the cement is replaced with recycled waste.

The most visible measure will be building the roof of the new pier (North Pier) in wood, not metal. Previously, the roof has been illustrated with shiny metal, but based on environmental and other considerations, a wooden roof has been chosen instead.

Illustration: The new pier, the North Pier, will have a wooden roof.

Reducing the energy needed to operate buildings is one of the major challenges facing the construction sector. Oslo Airport is taking action by building the new departures and arrivals hall and the North Pier as passive energy buildings. The new buildings will be so energy-efficient that it is estimated that they will consume half as much energy as the current terminal.

Focusing on public transport

We want to facilitate the use of public transport to and from the airport, and are therefore expanding the railway station. In 2013, the public transport share was 65%, the highest percentage in Europe. Our goal is to see as many as 70% of those travelling to and from the airport using public transport by 2020.

BREEAM certified as "Excellent"

The new departures and arrivals hall and North Pier will be certified as "Excellent" in the BREEAM Bespoke class. BREEAM is a well-known and widely used international environmental assessment method and rating system for buildings. Extensive use of wooden elements in the roof and our energy solutions worked in our favour during the certification process.

Sewage and snow as energy sources

We are building two new smart energy solutions that are not used by any other airports in the world, namely by taking advantage of local conditions to recover energy.

Sewage from the northern parts of Ullensaker, Nannestad and Oslo Airport will be recovered and used for heating. Snow from the past winter will be used to cool the North Pier. No airports recover heat from wastewater to the extent that Oslo Airport will be doing, and the thermal snow stockpile is the only one in the world.

The airport has its own district heating system where district heating is produced using environmentally friendly heat pump technology. The energy source is heat from treated wastewater. The distribution of energy to the individual buildings is through a culvert system with district heating and cooling pipes and is transferred to buildings in local heating plants.

Protecting the groundwater

During the winter, chemicals are used to prevent slippery conditions in runway and taxiway areas and formation of ice on aircraft. To protect the groundwater underneath the airport, all of the surface water is collected and piped to Ullensaker Municipality's treatment plant.

During periods of heavy precipitation and de-icing, the treatment plant does not have the capacity to accommodate all the water. It is then collected in large basins and released in portions to the municipality's treatment plant.

Here, the surface water is treated together with other municipal sewage. The water temperature increases when the contaminants in the water are broken down through the treatment process. When the wastewater from the runways, taxiways and sewers is treated, Oslo Airport "borrows" the water from municipality and extracts the heat from the water in a heat recovery station.

The heat is used in two ways:

The first is to inject the heat back into the surface water from the runways and taxiways that goes into the treatment plant. This increases the temperature of the water, increasing the degradation rate. In other words, we are increasing the capacity of the treatment plant. The second is to transfer the heat from the treated wastewater to the district heating system using heat pump technology.

In addition, some chemically contaminated surface water will infiltrate the ground along the runways and taxiways when the snow melts. This is purified naturally by the soil. As part of efforts to protect the groundwater, approximately 200 groundwater wells included in the airport's inspection and monitoring programme have been drilled.

The world's first airport with snow cooling

Huge amounts of snow are collected each winter at Oslo Airport. The snow is divided into two categories, pure and impure, i.e. whether it contains or does not contain de-icing chemicals from runway and taxiway de-icing.

The impure snow is piled and when it melts, the polluted water goes to municipal treatment plants and is preheated by recovered heat. The pure snow is allowed to melt naturally and sink into the ground. This is important for maintaining the water balance in the soil at Oslo Airport. It is part of the licensing requirements for operating the airport.

But first, the pure snow is collected in a large snow stockpile shaped like a basin. When it is full, the basin is covered with sawdust. Sawdust insulates well, allowing us to utilise the cold temperatures in the snow and ice. The coldness of the meltwater is recovered in a heat exchanger and transferred to the central cooling plant. The meltwater is returned to the stockpile to repeat the heat exchange with the snow and ice in the snow stockpile, followed by a new cycle of transmission of cold energy to central cooling systems. The energy in the snow and the cold meltwater are used to cool the North Pier on hot days.

As the snow and ice melt in the snow stockpile, the surplus clean meltwater is gradually released into the ground, which helps to maintain the water balance in the soil.

 Illustration: Kent Ekström