--- title: "Port Campbell: Geothermal Heating and Cooling for a Coastal Home on a Single-Phase Supply" date: 2024-11-06T20:28:00+11:00 author: Darren Burch canonical_url: "https://sogeo.com.au/case-studies/geothermal-home-heating-system-in-port-campbell" section: Pages --- ![Geothermal Swimming Pool]() # Port Campbell: Geothermal Heating and Cooling for a Coastal Home on a Single-Phase Supply A luxury new build on the Port Campbell coast with no three phase supply and salt air on every side. Horizontal ground loops, a Stiebel Eltron geothermal plant room beneath the indoor pool, a measured SCOP of 5.2 and a 70% reduction in the home’s power consumption. **Location**Port Campbell, Victoria**Project**New build, luxury coastal home with indoor pool**System**Ground source heating and cooling, pool heating and domestic hot water from one plant room**Ground loop**Horizontal trenches, 1.5 m deep and 1.5 m wide, in 240 m runs around the property**Heat pumps**Stiebel Eltron geothermal units for heating, pool and hot water; Daikin heat pumps for cooling through fan coils**Electrical supply**Single phase only, with limited amps and no three phase available**Measured result**SCOP 5.2, and the home’s power consumption cut by 70%**Delivery partners**Spence Builders (builder); Geo-Exchange Australia (engineering support)## The brief Richard and Ashley were building a luxury home in the coastal town of Port Campbell and wanted one sustainable system to do everything: hydronic underfloor heating, heated towel rails, an indoor swimming pool, cooling through fan coils in summer, and the home’s hot water. SóGeo was engaged to design and install a low-energy geothermal heating and cooling system that could carry all of it. ## The challenge Two constraints shaped the whole design. The first was power. The site had no three phase supply and only a limited number of amps on single phase, so every kilowatt of heating and cooling plant had to be justified against the switchboard. A heat pump’s electrical draw is the heat it delivers divided by its coefficient of performance, and a ground source system’s stable source temperature is what keeps that draw low at the coldest and hottest hours, which is exactly when a maximum demand assessment looks. Our guide to [maximum demand and heat pumps](/blog/geothermal-heat-pumps-in-melbourne-sydney-reduce-connected-load-and-save-on-electrical-upgrades) and our free [maximum demand calculator](/tools/maximum-demand-calculator) show the arithmetic. The second was the sea. Salt air corrodes conventional outdoor heating and cooling equipment quickly, so the plant had to live somewhere the weather could not reach it. We housed the heat pumps and associated equipment in a plant room beneath the indoor pool, fully protected from the elements, which extends the operating life of every component. 01 ![JLYY9678]() ### The system Ample land made a horizontal ground loop the right answer, and the indoor pool gave the plant room a home. With plenty of open ground on the property, we installed a horizontal geo-exchange rather than drilling. The trenches were excavated 1.5 m deep and 1.5 m wide in 240 m runs around the site, with the loop pipework laid and backfilled to form the ground heat exchanger. Stiebel Eltron geothermal heat pumps carry the heating load for the house, the indoor pool and the domestic hot water. For cooling, Daikin heat pumps distribute conditioned air through fan coils and linear bar grilles, so the home gets true summer cooling as well as winter warmth. The indoor pool hall received an energy recovery ventilation system to hold a comfortable climate and manage humidity while minimising energy use. The installation ran for roughly a year from project start to handover, in step with the build, and was delivered in collaboration with Spence Builders, who constructed the home, and Geo-Exchange Australia, who provided engineering support for the geothermal system. SóGeo designed the plant room and hydronics, and installed and commissioned the system. 01 ![IMG 5572]() ### The results Measured in operation, not on a datasheet. The completed system moves heat between the ground and the home all year, heating in winter and cooling in summer, and it cut the home’s power consumption by 70%. Despite the coastal climate and a high heating demand that includes an indoor pool, the system achieved a seasonal coefficient of performance (SCOP) of 5.2: across the season it delivered 5.2 units of heat for every unit of electricity it used. SCOP is a measured figure taken from the system in operation, not a datasheet rating, which is why we quote it rather than a laboratory COP. All of that runs on the original single phase supply, with no three phase application and no network upgrade. In Richard and Ashley’s words: “We are thrilled with the outcome of the project! SóGeo came with the skill needed to install our geothermal heating system, and we were impressed with how it seamlessly integrated into our home. The reduced energy consumption and amazing system design certainly exceeded our expectations.” 01 ![IMG 5598]() ### What made it work The design decisions behind the number. - **Designing to the supply, not around it.** Because a ground source heat pump holds its efficiency at the design extremes, its peak electrical draw stayed within the single phase supply. The same home on air source or electric resistance plant would almost certainly have needed a supply upgrade. - **Putting the plant where the sea cannot reach it.** No outdoor condensers, no corrosion, and a quieter home into the bargain. - **One loop, every load.** House heating, pool heating, hot water and cooling all share the same ground heat exchanger, sized on our 30-year design horizon so the ground temperature stays within the heat pumps’ limits for decades. ## Related How the technology works: [ground source heat pumps](/ground-source-heat-pumps). The full picture on choosing a system: [geothermal heating and cooling systems in Australia](/blog/geothermal-heating-and-cooling-systems-australia-guide). Underfloor as the distribution: [hydronic underfloor heating](/hydronic-heating-cooling/hydronic-underfloor-heating-comfort-efficiency). More projects: [SóGeo case studies](/case-studies). *Planning a coastal build or a home on a tight electrical supply? [Start with a site visit and a heat-loss calculation](/contact-us).* ![](https://sogeo.com.au/uploads/general/Case-Studoes/Pt-Campbell/_768xAUTO_crop_center-center_none_ns/3986/NMFT5801.jpg) ![](https://sogeo.com.au/uploads/general/Case-Studoes/Pt-Campbell/_768xAUTO_crop_center-center_none_ns/3978/IMG_5459.jpg) ![](https://sogeo.com.au/uploads/general/Case-Studoes/Pt-Campbell/_768xAUTO_crop_center-center_none_ns/3985/JLYY9678.jpg) ![](https://sogeo.com.au/uploads/general/Case-Studoes/Pt-Campbell/_768xAUTO_crop_center-center_none_ns/3980/IMG_5585.jpg) ## Contact Us For more information about our services and how we can help transform your heating systems, contact us today. ## Our Partners [ ![Reece](https://sogeo.com.au/uploads/suppliers/_AUTOx96_crop_center-center_none_ns/Reece.png) ](https://www.reece.com.au/) [ ![Stiebel Eltron](https://sogeo.com.au/uploads/suppliers/_AUTOx96_crop_center-center_none_ns/Stiebel-Eltron.png) ](https://www.stiebel-eltron.com.au/) [ ![Mitsubishi](https://sogeo.com.au/uploads/suppliers/_AUTOx96_crop_center-center_none_ns/Mitsubishi.png) ](https://www.mitsubishielectric.com.au/) [ ![Purmo](https://sogeo.com.au/uploads/suppliers/_AUTOx96_crop_center-center_none_ns/Purmo.png) ](https://www.purmo.com/au) [ ![Viessmann](https://sogeo.com.au/uploads/suppliers/_AUTOx96_crop_center-center_none_ns/viessmann_wordmark_rgb_1_vitorange.png) ](https://www.viessmann.com.au/)