Life Begins At.....
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ECO HOMES As with all things, carefully consider price and quality to ensure your home's best option. Always get at least three suppliers to quote for the same size system so you are able to compare prices. Ask for details on the type and quality of solar panels and inverter. Also make sure that the installer has Clean Energy Council accreditation. Solar hot water Installing a solar hot water system is one of the best ways you can save money on energy bills and reduce your impact on the environment. Heating water accounts for 30 per cent of an average Australian household's energy use. A solar water heater can reduce your emissions by as much as four tonnes of carbon dioxide per year – the equivalent of taking one large car off the road – simply by using the sun's energy to heat water at zero cost. The purchase price will probably be higher than a similarly sized non- solar water heater but the savings in energy bills will often pay for this difference in less than 10 years. A solar hot water system generally has a longer lifespan than a conventional unit, so financial returns can be considerable over the life of the system. Solar hot water systems range from $3,000 to $8,000, with a system for an average household about $5,500 before rebates. State and federal government rebates are available to offset the initial cost of a solar hot water system. Solar hot water systems use solar collectors (in the form of panels or tubes) to absorb energy from the sun. Water is heated by the sun as it passes through the collectors and then flows into an insulated storage tank for later use. Some systems pass anti-freeze through the panels instead; this transfers heat to the water tank via a heat exchanger. 146 THE RETIREE SUMMER There are two types of solar collectors: flat panel and evacuated tube. Flat panel collectors consist of a dark-coloured metallic absorbing plate to which a network of pipes is bonded. This arrangement is then placed in a sealed metal box with a glass cover on the top and insulation on the back and sides to reduce heat loss. As the sun shines on the collector panel, the water in the pipes becomes hot due to conduction from the collector plate. Evacuated tube collectors consist of two glass tubes (one inside the other) that are bonded to each other at each end to form a sealed space between them (although there are single tube types too). The surface of the inner tube is coated with a heat-absorbing coating. The space between the two tubes has most of the gas removed from it (hence they are evacuated), which provides a high level of insulation, just like a thermos flask. Evacuated tube collectors are suited to colder climates as they can perform well even on cloudy days. Hot water flows into tanks either by a passive or active system. In passive systems, the tank is placed above the solar collectors so that cold water sinks into the collectors, where it is warmed by the sun and rises into the tank. A continuous flow of water through the collectors ist created without the need for pumps. In active systems, solar collectors are installed on the roof and the storage tank is located on the ground or another convenient location. Water is pumped through the solar collectors