Hot water systems
Water heating accounts for up to 40 percent of energy used in the home. So a wise choice about which hot water system you buy can make a substantial difference to your energy bill.
The amount of hot water used by a household can vary widely and depends on the daily amount of bathing, clothes washing, cooking and dishwashing. The average family uses about 90 – 120 litres of hot water each day.
When you install a hot water system in a new house, or replace an old system, give some thought to the type of system that best meets your needs. After all, the purchase of a hot water system entails a significant initial cost outlay, as well as a commitment to buy energy for the expected 10 – 15 year life of the system.
The main energy sources for hot water systems in Queensland are electricity, gas and solar.
Why choose solar?
Economical – a solar hot water system can reduce your hot water bill by up to 80 percent so you can recoup the purchase cost over time.
Reliable – provided you have a suitable sized tank and booster system installed, you should have a reliable supply of hot water at night and during cloudy days.
Environmentally friendly – a solar hot water system uses solar energy instead of electricity or gas to heat water, reducing fossil fuel use and hence reducing greenhouse gas emissions. Each solar hot water system installed reduces carbon dioxide emissions by an average 2.5 tonnes a year.
Types of solar hot water systems
Thermosyphon system – can be either close-coupled with the tank on the roof above the panels or have the tank inside the roof and above the panels.
Forced (pumped) circulation system – panels are located on the roof, the tank at ground level and a small pump circulates the water through the panels into the tank.
Solar boosted heat pump system – uses heat exchanger panels to absorb heat energy from the ambient air.
For more information, download the fact sheet Solar hot water: Powered by the sun's natural energy.
Tips for solar hot water systems
- Conserve hot water by using it efficiently. Follow the manufacturer’s recommendation for maintenance of your solar hot water system.
- When possible, do jobs requiring hot water early in the day, so the water remaining in the tank is reheated by the sun, reducing the need to use the booster.
- Choose the type of booster carefully. Different types available include gas and electric.
- The recommended setting for the booster thermostat is approximately 60° C. The lower the thermostat setting the less energy used to supplement solar heating.
For all hot water systems
- Insulate the first two metres of the hot water pipe from the hot water system.
- Reduce your running costs by connecting your hot water system to the most economical tariff – check with your electricity supplier.
Last updated: 16 April 2007
