High-demand commercial buildings rely on hot water every day. Q-ton air-to-water heat pump systems are reducing the energy use, running costs and emissions behind that supply.
Commercial hot water rarely receives the same attention as air conditioning, lighting or major plant, yet in most facilities it runs constantly. In healthcare, aged care, hospitality, education, food processing and manufacturing, it supports everything from hygiene and cleaning to comfort and production. When the system behind it is inefficient, expensive to maintain or reliant on gas, the impact shows up in energy bills, maintenance programs and emissions targets.
Glen Alcock, product executive at Mitsubishi Heavy Industries Air Conditioners Australia (MHIAA), says that makes hot water an immediate opportunity for asset owners seeking lower energy use while meeting daily demand.
“Hot water isn’t something people tend to focus on, but it accounts for a substantial portion of energy use across many commercial buildings,” he says. “Collectively, commercial buildings consume around 25 per cent of Australia’s electricity and are responsible for about 10 per cent of national carbon emissions.”
That takes the discussion from hot water volume to how that supply is generated. In existing facilities, many sites still rely on gas boilers and electric heaters installed at construction, sometimes decades ago. As those systems age, maintenance becomes more frequent and expensive, while high energy use continues to weigh on operating costs.
“In a lot of those facilities, particularly aged care, asset owners have traditionally maintained existing systems for as long as possible,” says Alcock. “What we are seeing now is extensive maintenance, regulatory requirements and rising energy costs forcing upgrades and accelerating the shift to more efficient systems.”
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For new builds, gas is no longer the assumed choice. In Victoria, all new homes and most new commercial buildings will be required to be built all-electric from 2027 as the state accelerates its transition towards net zero. As gas is phased out of many new building designs, specifiers are assessing hot water systems for high-temperature supply, peak demand and lower energy consumption.
“It isn’t just a maintenance decision anymore. It is about operating cost, energy use, emissions and compliance,” says Alcock.
MHIAA’s Q-ton gives commercial buildings a lower-energy alternative to gas boilers and conventional electric systems.
Traditional hot water systems generate heat directly, either by burning gas or using electric heating elements. Q-ton works differently. As an air-to-water CO₂ heat pump, it captures heat from the surrounding air and raises it to a much higher temperature.
The process uses a refrigeration cycle. CO₂ refrigerant absorbs that heat, then passes through Q-ton’s two-stage compressor, which combines rotary and scroll technology. Compressing the refrigerant increases its pressure and temperature. That heat is then transferred to the water through a heat exchanger, producing sanitary-grade hot water between 60°C and 90°C for commercial applications.
“This process, coupled with other technologies, allows it to achieve a coefficient of performance (COP) of up to 4.3, meaning it can deliver more than four times the heat energy compared to the electricity it consumes,” says Alcock.
“Q-ton also uses CO₂, a natural refrigerant with a global warming potential (GWP) of just 1. It produces up to 74 per cent fewer emissions than an electric heater and up to 76 per cent fewer emissions than a gas boiler for the same application.”
In high-demand environments such as healthcare, aged care and hospitality, the savings accumulate quickly because hot water systems operate continuously. Q-ton can reduce running costs by up to 76 per cent compared with electric water heaters and up to 46 per cent compared with gas boilers.
Lower emissions don’t limit its high-temperature performance. Q-ton is designed to operate in low ambient temperatures, producing hot water in conditions down to –25°C and maintaining full capacity down to –7°C.
“That capability is supported by the compressor technology,” says Alcock. “The two-stage compressor allows the system to continue extracting heat from the air and lifting it to the required temperature, even in colder conditions. That makes it suited to colder regions and process-based operations such as distilleries, where year-round hot water is critical.”
For hygiene and compliance, Q-ton includes a dedicated anti-legionella cycle that periodically superheats the water to 70°C to eliminate bacteria and maintain sanitary conditions.
Alcock says this feature is important in environments where water quality is critical, including healthcare, aged care and other facilities with strict hygiene requirements. For operators, it helps confirm that the hot water system is supporting safety and compliance as part of day-to-day operations.
Q-ton’s modular configuration allows it to adapt across different building types. Its compact design supports both retrofit into existing hot water systems and specification in new developments, with a smaller footprint than traditional boilers.
“Q-ton can be installed as a stand-alone unit or scaled up to 16 units in tandem, delivering up to 100,000 litres of sanitary hot water per day,” says Alcock.
“In retrofit applications, most of the work is centred around the plant room where the units and storage tanks are installed. For new builds, the system can be designed in early and configured to suit the project’s hot water requirements, without relying on a single large piece of equipment.”
Each installation can be controlled through a single touchscreen controller, whether it is one unit or a multi-unit system. That allows operators to set temperatures and manage the system centrally. It also enables scheduling, so hot water can be generated during off-peak periods and stored in tanks, helping to reduce running costs.
Building management system, or BMS, integration gives operators deeper operational visibility.
“In new builds, that integration is important, as most projects already include BMS platforms to manage building services and overall efficiency,” says Alcock.
Since entering the Australian and New Zealand market in 2017, Q-ton has been installed across a range of projects, including Warrigal Aged Care in Wollongong.
The brief centred on reducing the client’s running costs and emissions while maintaining reliable hot water supply for residents and staff, with six Q-ton systems and more than nine 1,000-litre stainless steel tanks installed.
Alcock points to reduced energy use, lower operating costs, reduced carbon emissions and a more reliable hot water supply among the key outcomes.
“That reliability is important in aged care, because hot water is part of daily resident care, cleaning and hygiene,” he says. “Hot water isn’t an area where facilities can afford frequent interruptions.”
Another example is the Lark Distillery in Tasmania, where the site was relying heavily on gas in a cold, remote location. The move to Q-ton delivered an operating cost reduction of around 40 per cent at the time of installation.
MHIAA is also supplying systems into the $835 million John Hunter Health and Innovation Precinct redevelopment in Newcastle, where 12 Q-ton units are being installed.
“These projects show where the system carries the greatest value: high-demand facilities using hot water every day,” says Alcock.
Rebates strengthen the commercial case. Q-ton is currently eligible under the Victorian Government’s Victorian Energy Upgrades (VEU) Program and the NSW Government’s Energy Saving Scheme (ESS), allowing eligible businesses in those states to access thousands of dollars in potential rebates when replacing inefficient hot water systems.
Lower upfront costs may help a project proceed, but the value is proven after installation. For Alcock, that comes down to continuity of supply.
“Q-ton systems are engineered and manufactured in our state-of-the-art facility in Japan, with a focus on build quality and component reliability,” he says.
“That translates into systems designed to operate continuously in demanding commercial applications, with a long product lifespan. Reliability means fewer interruptions, minimal maintenance requirements and a consistent hot water supply.”
Policy settings, rising energy prices and emissions targets are changing the economics of commercial hot water. Air-to-water heat pump systems are giving high-demand buildings a lower-energy way to protect supply, reduce operating costs and cut emissions.
