A recent industry study conducted for the Northern Territory Department of Logistics and Infrastructure (DLI) is challenging long-standing approaches to HVAC system selection in commercial buildings with significant implications for energy use, emissions, and lifecycle costs.
The findings highlight a clear opportunity for building owners, consultants, and contractors to rethink traditional system choices and adopt more efficient, future-focused solutions.
Why This Matters
For years, HVAC system selection has typically followed simple rules of thumb: smaller buildings use packaged systems, medium loads use air-cooled chilled water, and large facilities rely on water-cooled systems. While practical, this approach has not always delivered optimal outcomes in energy efficiency, environmental impact, or long-term cost.
What Was Studied
The study compared packaged (DX) systems, air-cooled chilled water systems, and water-cooled chilled water systems across multiple Northern Territory climates including Darwin, Alice Springs, Tennant Creek, and remote communities. Each system was assessed over a 40-year lifecycle considering energy, maintenance, capital costs, refrigerant impact, and emissions.
Key Findings
1. Chilled Water Systems Reduce Emissions
Air-cooled chilled water systems produced approximately 30% lower lifetime emissions than packaged systems, largely due to the use of low Global Warming Potential (GWP) refrigerants.
2. Water-Cooled Systems Offer Highest Efficiency
Water-cooled systems achieved up to 35% emissions reduction in dry climates and around 20% in humid climates, although higher capital and maintenance costs must be considered.
3. Operating Hours Drive System Selection
Buildings operating 24/7 benefit significantly from water-cooled systems due to energy savings, while standard business-hour buildings often favour air-cooled systems.
4. Climate-Specific Design is Critical
Dry climates improve water-cooled system efficiency, while humid climates reduce the benefit. System design must reflect local environmental conditions.
5. Maintenance Must Be Considered
Cooling tower scaling in high mineral areas increases maintenance costs and impacts lifecycle performance, reinforcing the need for practical design considerations.
What This Means for Building Owners
The study confirms a shift toward chilled water systems for medium to large buildings, with increased emphasis on lifecycle performance, emissions reduction, and refrigerant selection.
Our Perspective at Sirius Air
At Sirius Air Conditioning & Refrigeration, we are seeing these trends across commercial projects. We help clients select systems that balance performance, cost, and sustainability while aligning with modern industry standards.
Looking Ahead
Smarter, data-driven HVAC design will be critical as regulations tighten and sustainability becomes a priority. Choosing the right system today has long-term impacts on cost, performance, and emissions.
Contact Us
Need advice on the right HVAC system for your project? Contact Sirius Air Conditioning & Refrigeration to discuss your requirements.