"Currently out of 2.1 million households only 10,000 use solar hot water systems," said Louis Delacretaz, the Greens Energy spokesperson. "However, as the average electric or gas unit lasts around 15 years, our installation and replacement proposal would see up to 100,000 solar hot water systems installed across Victoria each year."

A complete change over to solar could potentially reduce the state's greenhouse gas production by at least 2.2 million tonnes each year. Hot water accounts for about 27 per cent of residential carbon dioxide production in Victoria. Switching to solar hot water would cut that in half, that is, reduce household greenhouse gas emissions by around 13 per cent.

Find out more about the Greens Energy policy.