Victoria could capture enough energy from the sun to meet its electricity needs twice over and trails other parts of the world in harnessing wind power, says the national Climate Commission.
The latest report by the Tim Flannery-led commission, on climate change impacts and opportunities for Victoria, suggests the state has barely begun to tap its renewable energy sources.
It is estimated that Victoria receives at least 2500 petajoules of usable solar energy on available land every year – more than double the amount consumed across the state in 2009-10, when demand for electricity peaked. The greatest solar potential lies in the state's north-west, near Mildura.
On wind power, the commission says installed generation is only a fraction of what could be harnessed. It contrasts the state with Denmark, which is more densely populated and has similar onshore wind speeds but in 2010 had seven times more wind energy.
Commission member Gerry Hueston, a former BP Australasia president, said Australia, and Victoria, had made a start in encouraging renewable energy, but investment had been held back by political uncertainty. "There is a tremendous amount of opportunity provided you get the right policy settings in place," he said.
There have been calls for laws requiring 20 per cent of electricity to come from renewable sources by 2020 to be scrapped following the introduction of a carbon price, but Mr Hueston said the target would drive wind power development and gave businesses some confidence that a climate policy would survive. "We need a bipartisan approach and to not seeing chopping and changing," he said.
On climate science, the report finds that the annual number of days hotter than 35 degrees in Melbourne has increased from 10 in the last century to 13 in the past decade, and is projected to be between 15 and 26 by 2070.
It says the number of "very high" and "extreme" fire danger days is likely to increase, and heat-related deaths are expected to rise 40 per cent by 2050. Much of Victoria's infrastructure is not designed to withstand extreme temperatures, it warns.
The report says sea level rise is tracking close to the upper range projected by scientists, with areas most at risk including Melbourne's bayside southern and western suburbs, east Gippsland and Geelong.