New Zealand’s second largest airport affirmed its commitment to sustainability by signing up to the Declaration on Climate Change, along with 300 other international airports, at the Aviation and Environment Summit held in Geneva in 2008.

It was also the first airport company in the Southern Hemisphere to achieve carbon neutral status and is one of only two carbon neutral airport companies in the world.

The company recently had its CarboNZero certification - first issued by Landcare Research in 2008 - renewed until 2013.  This certification requires Christchurch International Airport to monitor, manage, mitigate and reduce the greenhouse gas emissions resulting from its operational business activities.

Key sustainability actions include almost doubling the amount of waste recycled, the adaptation of the airport’s vehicle replacement policy to take fuel efficiency considerations into account and increasing the use of recycled asphalt pavement in its annual runway maintenance programme.

Furthermore, important mechanical functions such as the flight information display system, nose-in guidance, lighting control and fire and maintenance have been integrated in a smart Building Management System (BMS) with a view to optimising energy efficiency and occupant comfort.

At the heart of the new terminal is 3.6MW of water cooled chillers and variable speed pumps which distribute heated and cooled water around the building. The solution had to heat 11,720 litres of water per day to a temperature of 60 degrees Celsius, achieving an energy saving of up to 70 per cent.  The brief to mechanical services consultant Beca was to provide energy efficient, robust mechanical services solutions, within the budget.

The installed product was a Performance Plus electric air-to-water heat pump. Bespoke manufactured for Christchurch International Airport by Hot Water Heat Pumps Ltd – an Auckland-based company with 30 years experience making heat pumps for water heating applications – it utilises the same refrigeration technology used in heat pumps, to heat water to a minimum of 60°C.

The Performance Plus heat pump does not burn fossil fuels, making it a clean energy product. It also produces significantly more energy than it consumes and has a longer “life expectancy” than some other forms of heating.

Paul Carrington, Commercial Manager of product marketer Parex Industries says, “The Performance Plus uses only around one-third the energy used by conventional electric element hot water cylinders to heat water, and this along with its being New Zealand made - making for ease of service and repairs - gave it an edge over competitor products.

“The best way to understand just how energy efficient the Performance Plus heat pump water heater is, is in terms of a measure called Coefficient of Performance which is a number relevant to the kiloWatt input of power versus the kiloWatt output of hot water.

“Four Performance Plus heat pumps were installed at Christchurch International Airport working in pairs, each unit has a maximum output of 23 kilowatts and input of only 5kW depending on the climatic conditions.”

Beca’s Justin Hill says the product met the specification with the benefit of being New Zealand made.

He says the arrangement provides an element of redundancy should one, or all of the heat pumps fail making it a robust and energy efficient solution.

The heat pumps supply hot water to the public washrooms and other amenities.

One set of heat pump water heaters are located in the plant room with the 3.6MW of water cooled chillers.  The chillers operate upwards of 20 hours a day, 365 days a year.  By effectively recovering the heat radiated from operating chillers the efficiency of the domestic heat pump water heaters is further increased, at the same time as cooling the plant room.

“Along with the other mechanical solutions chosen, the heat pumps were selected due to their cost effective, energy efficiency benefits and their capacity to meet the hot water demands.

“It’s not ‘green bling’ - they weren’t selected to make a statement about Christchurch International Airport’s commitment to the environment, but rather to be actively environmentally conscious,” says Mr Hill.