Australians are world leaders in rooftop solar and home batteries - but greater energy efficiency could make them a triple threat

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For David and Ruth Hudspeth, the process of turning their 1950s brick veneer house in Melbourne’s eastern suburbs into a cosy, efficient and fully electric home took several years.

They started with insulation in the ceiling and replacing an old and “pretty dangerous” gas heater. They swapped their leaky hot water system for a heat pump, and built a roof over the outdoor deck for shade and extra solar panels, later adding an electric car and a home battery into the mix.