Knoxfield Sustainable House New home designed by Sunpower Design Climate Zone: Victoria - Temperate coastal zone
This house was built for my retirement seven years ago and was planned to have as many sustainable features as possible. The design takes advantage of the natural world, harnessing the warmth and energy of the sun for internal comfort, hot water and electricity. My house makes up part of the normal suburban landscape yet uses no mains water and sends its surplus electricity into the grid. It is comfortable to live in, being warmer in winter and cooler in summer with reduced running costs.
Passive Solar Design – correct orientation, double glazed windows facing north to allow heating from the winter sun, adequate thermal mass (concrete slab) to store the heat, good insulation, and windows designed for cross ventilation to facilitate cooling during summer evenings.
Rainwater Collection – rainwater flows through Smartflo gutters, and a first flush device system into a 26,240L polyethylene tank which is partially set into the ground. A further filter is located under the kitchen sink for drinking water. The house runs entirely on rainwater.
Grey Water System – bathroom and washing machine water is treated to class A standard by passing through biologically active peat, stored and aerated. Grey water is used for toilet flushing and garden use. Trinature and Melrose products are used for their low environmental impact.
Solar Hot Water – AAE solar hot water using evacuated tubes has recently replaced a flat plate solar system that supplied 6-7 months free hot water per year. I anticipate greater efficiency with the AAE system.
Solar Electricity System – original PV array was a 2.4 kW grid interactive system with a small battery bank. It was installed on a north facing roof at latitude angle ie. 38 degrees. A further solar upgrade of 2.1 kW was added above the upstairs bedroom at the beginning of 2008 making a total of 4.5 kW. Last year the system produced more electricity than the house used and my account was in credit.
Passive Solar Heating – in 2008 a SolarVenti SV14 was installed in the upstairs bedroom, and a SV30 for the living area. Both units face north and when the sun shines, a fan is activated by a small photovoltaic panel in the units transferring warm air into the relative areas. There are no running costs as the system is powered by the sun.
Water Efficient Garden – As the house relies completely on rainwater, the garden was designed to be as water efficient as possible. There is no lawn. Australian natives and drought tolerant plants that would grow in clay soils were watered with grey water until established and then mostly left to survive on their own. Coconut mulch was used as it discourages snails.
See more on the Knoxfield Sustainable House here: http://www.greenlivingpedia.org/Knoxfield_house
(August 2009) (
