HVAC under strain as El Niño bites

With the Bureau of Meteorology declaring an El Niño event for this summer, bringing with it warmer and drier conditions and an increased likelihood of heatwaves, HVAC systems in Australia’s million-plus commercial buildings will need to work harder than ever, producing higher energy bills and greater emissions.

“Given that all Australian state capitals already have many days exceeding 35–40 degrees, the Australian Standard* for offices and factories of 21–24°C is going to be under some large pressure,” said Michael Fisher, Managing Director of Boon Edam Australia, part of a global group specialising in architectural revolving doors and security entrances.

“Given that commercial buildings are responsible for about 24% of Australia’s total energy consumption, the pressure is going to be on to maximise efficiencies while minimising emissions from hard-working air-conditioning plant,” Fisher said.

Keeping commercial energy bills down

Building owners and managers particularly prone to higher energy bills, closer emission scrutiny and duty-of-care issues this summer include those in charge of:

• data centres and financial computing centres, which already draw large amounts of energy overall and face calls to reduce emissions;
• public and private office buildings;
• health centres, which have a particular responsibility to maintain even temperatures for their patients;
• hotels and retail centres concerned about guest and customer comfort (Australia has more than 1600 shopping centres of more than 1000 m², and about 6000 hotels and similar establishments);
• industrial workplaces, which have a duty of care for worker conditions, and also to maintain hygienic temperatures around delicate processes and perishable goods;
• Australia’s 10,000 primary, secondary, TAFE and university colleges, which accommodate more than 5.6 million students and academic staff (including more than 4 million primary and secondary students and about 1.5 million at higher education facilities).
   

“Many of our stock of a million-plus non-residential buildings are upgrading their HVAC systems to the best modern standards, while architects, builders and managers generally are paying far greater attention to producing ‘tight’ buildings that don’t leak expensively conditioned air and place greater load on plant,” Fisher said.

“Many also are highly aware of the amount of HVAC air that is dumped out onto the footpath every time a sliding or conventional door is used — which is nearly all the time in busy government and private buildings, particularly service and transport centres.

“We don’t pretend for a moment that revolving doors are a total answer to energy sustainability objectives — that is a multifaceted issue — but we do believe that some buildings have a sustainability blind spot when it comes to the obvious benefits of revolving door entrances, with their ‘always open, always closed’ functionality.

“One of the difficulties in the past has been actually measuring the doors’ impact on sustainability, and obtaining practical ROI information as the cost of energy continually goes up and the ROI continually tracks down.”

Measuring energy savings

Boon Edam — which operates in 27 countries globally — has set out to provide architects, builders and managers with a reliable estimation tool to quantify the gains.

The company partnered with Delft University of Technology (TU Delft) to develop a scientifically validated software that is now available in Australia, New Zealand and Papua New Guinea.

“The software’s science-based approach gives specifiers the chance to demonstrate to their clients what many of them have known for years: revolving doors offer permanent gains in energy efficiency across the spectrum of commercial building types, both existing structures and new buildings seeking NABERS or National Electricity Market (NEM) measurable sustainability credentials,” Fisher said.

The software was first used to test Sydney, Melbourne and Brisbane building models. It showed that the payback period for installing a revolving door, instead of a less energy-efficient sliding door, is shrinking rapidly as energy prices accelerate quickly. Calculated on this year’s prevailing energy prices (which are due to rise again early in 2024), Melbourne has the quickest payback time of four years, followed by Brisbane at 4.9 years and Sydney at 5.7 years and shrinking.

The energy calculation software quantifies the benefits of revolving doors compared to sliding doors when considering energy savings and prevention of draught. Users are provided with a format into which to enter specific data for their facility, which is then processed by the new Boon Edam propriety software. The software calculates and reports on data including:

• energy savings in kWh per month throughout the year when a revolving door is installed instead of a sliding door;
• payback time of a revolving door compared to an automatic sliding door;
• the area of the floor behind both door types, where according to DIN standards, serious discomfort from draught can be expected.
   

Fisher said that for building specifiers seeking to achieve green performance ratings, it can no longer be a question of ‘What is the cheapest door upfront?’, but rather ‘How can we create a sustainable, secure and comfortable environment that meets national and global standards of sustainability and returns benefits starting immediately and extending over decades?’

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Image credit: iStock.com/ DNY59