An energy-autonomous home in Melbourne - myth or reality?

Energy-autonomous buildings are possible. Completely energy self-sufficient houses can be found, for example, in Europe. If it is possible to cover the entire energy demand of a household from only renewable energy generated on site in a central European climate, what is required in a temperate climate, typical of southern Australia? This paper describes an investigation to broadly assess the technical, practical and financial feasibility of energy-autonomy for a hypothetical suburban house in Melbourne, Victoria. The findings firstly demonstrate the importance of reducing energy demand by using passive solar building strategies and energy efficient appliances to reduce demand to a reasonable level. The paper then discusses four scenarios and combinations of technologies to meet this reduced demand. The three scenarios which give energy autonomy increase the capital cost of a typical house by between 15% and 3%, and there would be insufficient roof area to accommodate the solar technologies required in two of the scenarios investigated. It is therefore concluded that while the goal of energy autonomy is technically feasible, it is not likely to be financially or practically acceptable. A fourth scenario of an energy-exporting house was also investigated and is shown to be a much more attractive option.