Challenge
Reducing Energy Costs and Carbon in a Heat-Intensive Industry
MainStream Aquaculture operates a major barramundi breeding and grow-out facility in Werribee, housing eight 600 kL grow pools heated by two 650 kW natural gas boilers. Heating water to 29 °C is energy-intensive, and with 11 smaller gas boilers also onsite, the business was seeking to cut both operating costs and emissions without compromising water quality or fish health.
Solution
Engineering the Switch from Gas to Geothermal-Electric Heat Pumps
With a $19,000 Victorian Government Large Energy User Electrification Support Program grant, MainStream Aquaculture commissioned Northmore Gordon to do a detailed electrification feasibility study.
The study explored two primary solutions:
• Option 1: Replace the two 650 kW gas boilers with a 550 kW water-to-water heat pump, tapping into geothermal bore resources for efficient heating.
• Option 2: Add a geothermal and trade waste heat pump to capture and reuse biosolid-rich water, reducing water wastage and recovering energy.
Northmore Gordon’s modelling included thermal storage integration, boiler consolidation into an electrified system, and staged scalability to support future site expansion.
Forecast Results
Commercial, Environmental and Strategic Gains
• $113,000 annual energy cost savings projected.
• 70 % reduction in annual gas use – equivalent to 537 tCO₂ avoided every year.
• 10,413 GJA gigajoule (GJ) is the equivalent to 1 billion joules. A joule is a measure of the energy required to send an electrical current of one ampere through a resistance of one ohm for one second. One GJ is equal to 277.8 kilowatt hours ( kWh), 1.055 million British thermal units (Btu) or 0.17 barrels of oil. annual gas reduction.
• 3,125 VEECs created – each representing one tonne of greenhouse gas abated.
• VEUVictorian Energy Upgrades is a Victorian government energy efficiency program that gives every Victorian household and business the opportunity to receive rebates or discounts on energy saving products. incentives worth up to ~$281,250 identified.
• Simple payback: 5 years.
• Net Present Value (NPV): $596,000.
• Positions the business as a sustainable aquaculture leader with a strong circular economy approach.
Program Context
Turning Feasibility into Action
MainStream Aquaculture was one of 36 facilities in Victoria to receive support under the Large Energy User Electrification Support program, which provides grants of up to $60,000 for commercial and industrial sites using 10–100 TJ of gas per year. These feasibility studies are designed to underpin Project Based Activity (PBAProject Based Activities) retrofits under the Victorian Energy Upgrades program, enabling accredited providers to create VEECs for each tonne of CO₂ avoided.
Northmore Gordon View
This is a textbook example of “Do more with less energy” – the opportunities were previous uncovered in an energy audit by Northmore Gordon with this latest report using engineering-led electrification, smart thermal integration, and certificate optimisation to deliver cost savings, emissions cuts, and long-term operational resilience. With industrial-scale heat pump technology now capable of replacing high-load gas boilers, businesses like MainStream Aquaculture can convert regulatory programs into significant financial advantage while driving sector leadership in sustainability.
Book a consultation with our senior engineering team to explore your site’s electrification potential.
Call or email Craig Morgan today or submit your interest here.
