Two years of careful monitoring of energy use has paid off for Wellington's largest office block.
After halving its energy consumption, the Asteron Centre has earned a 5.5 star base building energy rating from NabersNZ for reducing its base building energy use annually to just 46kW/hours per square metre.
Crown building performance specification requirements for tenancies they occupy generally vary between 105 and 120kW/ hours per sqm.
NabersNZ is a rating system that measures the energy performance of commercial office buildings.
Based on the National Australian Built Environment Rating System, it is a voluntary tool that measures energy use against factors such as building occupancy, number of computers and rentable area.
Comparing this against other similar buildings and climate conditions provides a rating on a six- star scale.
The Asteron Centre, which was completed in 2010, was designed to maximise environmental sustainability and has a 5 Green Star office design rating.
But the owners believed there was potential to make further savings.
Aurecon lead mechanical engineer Marcus Welby said every piece of plant was individually reviewed and all sensors were checked to optimise performance.
"We monitored the building five days a week to look at what changes could be made.
Effectively, it's about getting the best out of the millions and millions of dollars worth of the very complex equipment that has been installed."
The 49,000sqm 17-level Asteron Centre opposite Wellington Railway Station was designed by Warren and Mahoney and engineering consultancy services were provided by Aurecon.
Energy-saving features include rainwater harvesting, automatic dimming lighting when sufficient daylight is available, heat recovery chillers, high performance glazing, hot water pre-heating from chiller waste heat, chilled beams and heat pump hot water cylinders.
The building, which houses more than 2700 workers, is owned by Grant Corleison and Mark Dunajtschik.
"This award is great news for our tenants," Corleison said.
"The drastic savings we've achieved ultimately benefit the tenants who pay for their own consumption while we pay for the common areas.
"The lower we can get the energy consumption, the better it is for landlord and tenant.
"We're delighted with the work the engineers did on this."
Aurecon will also be working with the developers on Dunajtschik's proposed Hilton Hotel and conference centre project opposite Te Papa.
The only other New Zealand building to achieve a 5.5-star Nabers rating is the Meridian Energy head office on Wellington waterfront.
- The Dominion Post
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