David and Samantha dream of making their home the most sustainable in Ku-ring-gai Council and have been taking slow, well-planned steps to make this a reality. With a substantial amount of progress made they would like to share their journey.
What was the house like when you moved in?
David: “The house was run-down but liveable when we moved in as a young family. We decided to adopt a ‘systems approach’ to improving the thermal comfort and sustainability of our home. “Every house is a system that takes in resources such as food, water, energy and materials and produces waste water, carbon emissions and rubbish. In our wealthy society, we now have an ability to change this. We can generate our own resources such as energy and reduce or eliminate our waste”.
The family started work as soon as they moved in. Situated at the bottom of a hill it is cold in winter, so insulation was the first and most important priority. Patchy old ceiling insulation was replaced by R4 wool batts, as well as additional underfloor and wall insulation. The 50W halogen downlights throughout the house were replaced with good quality 7W dimmable LED lights. Though family baseload power use is low, a 5kW solar PV system was installed at first, soon upgraded to 9.3kW.
David: “The battery storage game will transform the energy system. We will get batteries and an electric car, when it is more affordable, though the issue isn’t so much about financial paybacks as about reducing environmental impacts.”
What is your advice on Solar PV?
David: “Use only Clean Energy Council accredited installers and make sure you get a monitoring system. Having solar without a monitoring system is much like driving a car with no fuel gauge and speedometer. The energy monitoring system helps me understand if how the solar PV is functioning, the amount of power I’m drawing and sending back to the grid and also the immediate impact of cranking up the AC, among many other facets of energy use.” They would like to stop using LPG in a bid to electrify the house completely and power it only with renewables.
David: “We have gas bottles delivered for cooking and instant gas hot water. Eventually we want to move to induction cooking and heat pumps. Natural gas is touted as a transitional fuel but renewables have now reached a price point where they are way more economical than gas.”
How do you find your house retains heating and cooling?
The house has a good north-facing aspect and lots of glazing which is great to let the sun in, but such single-glazed units also contribute to heat loss in winter. With good insulation and solar, they easily survived the exceptionally hot days this summer.
Samantha: “We cranked up the AC at the times when we were generating a lot of solar power and cooled the house for short periods and found the house remained cool for longer. Thick ceiling to floor curtains in bedrooms were found to work much better at keeping the house cool and retaining heat than roller blinds. But such choices are a matter of individual aesthetics.”
How have you made changes outdoors?
The family has been slowly transforming the landscape of their yard. The weed-infested lawns and bush are now planted out with over 200 native plants and fruit trees, and a series of impressive raised beds for vegetables.
David: “We built the garden beds with eco-timber and water them using a drip irrigation system set on timers. This also waters other plants around the garden with water from two rainwater tanks with a capacity of 15,000L. Trees are planted along boundaries so that animals can follow the wildlife corridor near the house. We also have a native beehive and tumbler compost in the garden which provides organic produce for the family.”
Future plans include setting up a grey-water system to re-use water, and a greenhouse in the front of the house to make the most of the solar aspect. They also would like to add another 18,000L of water storage to collect subsurface stormwater.
This family is proving that by taking one small step at a time you can have a big impact on the sustainability of your home, lifestyle and even local community.