The new Fairwater residential development in western Sydney claims to house Australia's largest geothermal system, according to the developers..
From an engineering perspective, geothermal systems are also commonly known as Ground Source Heat Pumps and operate in the same way as conventional air-conditioning systems, with a wall mounted thermostat, however they use the constant temperature of the ground to heat and cool as opposed to an external condenser and fan.
A geothermal system is comprised of three main components: the loop, the heat pump and the fan coil unit. When it comes to the actual installation in a home, the geothermal loops are installed vertically adjacent to each individual home to a depth of 80 metres.
Refrigerant is circulated underground via the loop then back to the surface, having taken on the temperature of the earth below, to heat or cool homes. When the system is in cooling mode, the heat is absorbed by the surrounding sub-surface ground.
According to Raymond Baksmati, development director, Frasers Property Australia, “Internally, the system is no different to a typical ducted air-conditioning system. Fan coils do not need to be adapted, nor do they require changes to internal design. All internal installations can be carried out by traditional air-conditioning contractors.”
The geothermal system at the McGregor Coxall-designed Fairwater is claimed to be able to save residents $1000 per year, which is a calculation done by Frasers and is based on a four-bedroom Fairwater home over a five-year period, compared to the average energy cost of a similar home in Blacktown, and is based on assumptions regarding equipment speciļ¬cations and usage patterns.
“The technology was originally estimated to save residents around $500 per year but a study earlier this year found that higher savings of between $713 and $1069 per annum were achievable, based on 100-150 days per year usage,” Baksmati says.
“In 2016, monitoring equipment was installed at a residence at Fairwater with data taken every five minutes for a period of nine months. Then, a two-week period in February 2017 was sampled to establish the system’s co-efficient of performance. In this period, temperatures ranged from 23 to 40 in the day and 19 to 26 in the evening.”
“In analysing the data, the energy co-efficient averaged at 6.75, which equates to a saving of $713 to $1069 per year. A typical air-conditioning system has a co-efficient of about 3.2,” he says.
“The geothermal heating and cooling technology is a key point of difference at Fairwater,” says Baksmati, adding that, “when installed, it was the largest geothermal community in the southern hemisphere and the first residential community to embrace geothermal on this scale.”