Solar hot water: it's an energy efficient choice, naturally

Electric water heating is the biggest energy user in NSW homes.

If you have an electric hot water system, it'll be responsible for up to one third of your household's power use. Choose a more energy efficient hot water system and you can reduce your reliance on coal-fired electricity, save power and black balloons.

Changing from an electric hot water system to solar, heat pump or gas hot water system is likely to be the single most effective move you can make to save power.

Solar hot water systems use energy from the sun to heat water at zero cost and produce no carbon pollution. While they cost more to buy than electric or gas water heaters, a solar or heat pump hot water system can pay for itself within 5-10 years depending on your household's hot water use.

Replacing your electric hot water system with a solar-powered heater can reduce your hot water system's power use by 70 per cent, saving you around $150 on your yearly power bills! You'll also reduce your household's carbon pollution by more than 2,000kg or up to 42,000 black balloons.

A solar hot water system uses the sun's energy to heat your water and can meet 50-90 per cent of your household's hot water needs.

Most solar hot water systems are supported by a booster that kicks in when there isn't enough sunlight to heat your water. These boosters run on electricity, gas (natural or LPG) or solid fuel. Gas is the most environmentally friendly option. If you choose an electric booster, try to connect it to an off-peak tariff to reduce your costs.

Before you choose your hot water system, consider your climate, house design, roof characteristics, water quality, available space, and aesthetic preferences.

Things to consider when choosing and positioning your solar hot water system:

• check the structural strength of your roof to ensure that it can support the weight of the solar hot water system – this can be assessed by a qualified installer
• ensure solar panels will not be shaded by trees or nearby buildings
• position the storage tank and solar panels as close together as possible to reduce the length of the connecting pipes
• insulate all pipes – if you live in a cold climate, you'll also need to protect the panels from frost
• choose the right size – a solar hot water system can be tailored to your family's needs by selecting an appropriate tank capacity and number of panels
• shelter your hot water system to avoid heat loss through draughts and wet weather
• ensure all plumbing and electrical work is carried out by a licensed contractor.

Contact your local council for information on regulations and any restrictions or special requirements for the installation of solar hot water systems in your area.

Get the most from your installed solar hot water system (HWS):

• do jobs requiring hot water early in the day to allow the water left in your tank to be reheated by the sun – this will reduce the booster-heating period
• install an override switch for the thermostat (or install a timer on the booster) to prevent boosting when there is sunshine available
• conserve hot water by using it more efficiently – consider installing a 3 star WELS (AAA-rated) showerhead for more savings
• follow the manufacturer's recommendations for maintenance of your solar hot water system
• ensure all plumbing and electrical work on your hot water system is carried out by a licensed contractor.

Replace your electric hot water system with a more energy efficient choice and save power and money. When deciding on the best hot water system for your home, solar may not be the best option.

Other hot water systems you may consider:

Natural gas

• comes in storage and continuous flow systems and produces far less carbon pollution than comparable electric systems
• is quicker to heat and uses a smaller tank than a comparable electric storage system
• compare systems using the Gas Energy Rating Label – aim for a system with the highest number of stars.

Electric heat pump

• is an efficient type of electric storage water heater that uses around 70 per cent less electricity than other electric water heaters
• draws heat from the air, water or ground to heat water – using about one quarter to one third of the energy of a standard electric storage system
• like a solar water heater, it costs more to buy and install but will pay for itself through far lower power bills
• can be made even more efficient by using a solar booster.

Remember, whatever type of hot water system you have, always turn it off when going away on holidays and periodically check the temperature is within the manufacturer's recommended range.