NEW ZEALAND: Air-source heat pumps are to replace six natural gas boilers, totalling 6.5MW, at New Zealand’s largest airport.
Auckland Airport, which handled 7.6 million passengers last year, is targeting a 90% reduction in Scope 1 and 2 emissions. Nearly half that is expected to come from eliminating the use of natural gas in the international terminal by the end of the decade.
The first heat pump, a 500kW Trane Sintesis Balance simultaneous heating and cooling unit, has been installed in Pier B of the 141,000m2 International Terminal, the leading contributor to Auckland Airport’s Scope 1 carbon emissions. Gas used by food and beverage outlets will be tackled in the coming years.
Describing the new installation, the airport’s chief sustainability and master planning officer Mary-Liz Tuck said: “Over a 12-month period we’ll use it for air conditioning the customs processing area and Pier B to really put it through its paces for not only the Auckland climate but those very ‘peaky’ heating and cooling needs across the day.
“There are very few sites in Australasia using this system at scale, so the team need to ensure it is fully road tested and fine-tuned for our specific airport needs before we begin investing in another 20 units, including heat pumps that solely heat or cool, to fully replace our gas-fired heating. We need to get this right.”
The fully electric HVAC replacement will be rolled out to coincide with construction at the international terminal including a planned upgrade to Pier A, the main departure and arrival point for international aircraft, and the new domestic terminal integrated into the international terminal.
“At Auckland Airport we move a lot of air – up to 12 air changes an hour in some of our big dwell spaces, Tuck said. “That currently requires about 15MW of cooling.”
A unique challenge in managing air temperatures within an airport terminal are the passenger ebbs and flows, which can see spaces like departure gates or arrival processing areas go from virtually empty to filled with hundreds of people then back to empty again within a short space of time.
“Unlike say a shopping mall, which has a fairly steady stream of people across the day in its public areas, many of the spaces in the terminal can be very dynamic in terms of foot traffic. It’s not necessarily something you’d notice as a traveller because you’re moving through the airport with people on the same flight but boarding and disembarking 300 to 400 seat aircraft in a short space of time can fill and empty processing areas quite quickly.
“While it creates complexity when you’re trying to keep different spaces at a comfortable temperature throughout the day and night, we can see some real opportunities to harness the warmth of one area to take the chill off another, or vice versa.”
The current heat pump is expected to save 30 tonnes of carbon per annum. Once all heat pumps have been installed, the expected saving is 1,500 tonnes of carbon per year.