What environmental and financial savings can be made using solar versus electric or gas hot water systems?

Generally about:

• 1 tonne of CO₂ and $250 per year saving compared to reticulated, natural gas
• 1 tonne of CO₂ and $500 per year saving compared to bottled LP gas
• 4 tonnes of CO₂ and $500 per year saving compared to electric.

However this depends on lots of variable factors such as models of systems, the water heating requirements of the household and whether we're talking about LPG or natural gas.

More detailed information is available in Hot Water Running Costs and Greenhouse Gas Emissions.

Do I qualify for a subsidy if I am replacing a gas, or wood-based, hot water system?

The State Government has no condition on what type of hot water system is replaced, only that an environmentally friendly, gas-boosted solar water heater is installed.

However, Renewable Energy Certificates (RECs) are only available for solar water heaters replacing electric hot water systems or solar water heaters installed in new homes. Although the Federal Government has announced it will remove these restrictions on eligibility for RECs, it has made no indication as to when.

Why is there no rebate on electric-boosted solar water heaters?

The Government of Western Australia is promoting the use of best practice, low greenhouse gas emission water heaters. Figures from SEDO's Hot Water Running Costs and Greenhouse Gas Emissions brochure show that gas boosted solar water heaters have the lowest greenhouse gas emissions of all common, residential water heaters. Additionally, gas-boosted solar water heaters have no impact on peak electricity demand or on the electricity network.

What's the point of giving a rebate on a product that costs more?

The Government of Western Australia is promoting the use of best practice, low greenhouse emission water heaters. Gas-boosted solar water heaters provide the best environmental outcome.

By targeting gas-boosted solar water heaters, the scale of production should increase and be reflected by downward pressure on retail prices.

While gas-boosted solar water heaters cost more to buy initially, they have much lower running costs compared to natural gas, bottled LP gas and electric hot water systems.

Are there any other rebates or financial assistance available to help me purchase a solar water heater?

Solar water heater suppliers offer a range of flexible payment options to assist with the purchase of a new solar water heater, including low interest finance. During Home Shows and other events some suppliers offer their own up front discount in addition to Government incentives available.

The Sustainable Energy Development Office recommends you seek several quotes from different suppliers before purchasing and remember you should consider the lower ongoing running costs in addition to the upfront costs in your purchase decision.

Will the Solar Water Heater Subsidy Scheme run out?

The Government of Western Australia plans to run the Solar Water Heater Subsidy Scheme for up to four years, or until the available funding of $1.6 million is fully committed. The rebate amount may be reduced during the life of the scheme, depending on take-up.

How can I compare solar hot water heater brands?

The most up-to-date comparison of the efficiencies of different solar hot water systems can be gained by comparing the number of Renewable Energy Certificates (RECs) allocated to any particular model. The more efficient the solar hot water system, the more RECs it will receive. Visit the Office of the Renewable Energy Regulator website for the latest information.

Edition 86 p56-62of ReNew magazine published information comparing brands and specifications of solar water heaters in January 2004. Visit the Alternative Technology Association's website for further information on its magazine.