Energy Smart Homes - Solar Hot Water

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Image of an unfitted solar hot water panel

Using the sun's energy to heat your water makes good sense.

Solar water heaters that use an efficiently controlled booster can reduce hot water bills by around 75% in Perth and more in northern areas. This can add up to thousands of dollars saved over the lifetime of the system.

Using an efficient solar water heater instead of an electric system saves around 4 tonnes of carbon dioxide emissions per annum which is as much as an average large car produces in a year. Carbon dioxide is one of the main gases responsible for the greenhouse effect.

The Government of Western Australia is offering subsidies of up to $700 off the standard cost of a solar hot water system purchased after 1 June 2005. See the Funding and Grants section for further information.

How do they work?
Solar hot water systems use the sun's energy to directly heat water, in much the same way as water in a hose left on the lawn gets hot on a sunny day.

Water heats as it circulates through flat, glazed panels (solar collectors) located on the roof of a house. The heated water is then stored in an insulated storage tank, usually located directly above the collectors. Some systems use a special fluid to absorb the heat energy from the sun, which is then used to heat the water stored in the tank.

Solar collectors typically consist of a blackened metal absorber plate within a glazed and insulated metal box (flat-plate collector). Waterways through the absorber carry the liquid to be heated.

An auxiliary heater (booster) is used to boost water temperature on days when solar energy is insufficient to meet all your hot water requirements. Boosting can be from electricity (standard or off-peak), gas (natural or LPG) or solid fuel (wood). Electric boosting is the most expensive way to run your solar hot water system and will result in more greenhouse gas emissions than using a gas-boosted system.

You can reduce the cost of boosting by manually switching the booster on only when needed or by using a 'boosting timer'. Timers can be set to boost overnight or during other periods when there is insufficient solar energy available, such as during winter and some cloudy days.

For further information, see the Solar Hot Water Systems brochure (PDF 900 KB).

Energy Smart Directory
For suppliers of energy efficient and renewable energy products and services, visit the Energy Smart Directory.

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