Water heating is the second biggest energy user in a typical household, so it makes a lot of sense to upgrade to the most efficient heater on the market. Typically solar hot water will pay back in 4-6 years, so it’s a pretty good investment.
It will be one of four systems:
Cheap and Nasty. Uses electricity to heat a resistive element (just like in a kettle) which heats water in a (usually) badly insulated tank all day every day whether you need it or not.
Sorry to be blunt, but if you have one of these, your financial priority should be to replace it ASAP. The Federal Government is generous with its cash if you want to upgrade one of these dinosaurs and will give you $1000 (Reduced from $1600 on 20 Feb 2010 in a classic bit of policy-on-the-run) towards the cost of the system plus various State Government incentives.
Each system will save you approx $500 per year, so it is usually a great payback. There are even firms who will let you pay interest free over a few years.(Oh and if you want more info on all things Solar Hot Water, and maybe even get 3 quotes for a solar hot water system, I've put everything I know here: www.SolarHotWaterQuotes.com.au)
If you’ve got one of these, it’s gonna be at least 7 years old as everyone installs instant gas these days which heats the water as and when you need it. I upgraded mine last year and it cost $1800 installed and saved 30% off my gas bill.
These are usually 5, 6 or even 7 star energy rated and are very efficient. You will use less gas if you add a solar hot water system to one of these, but the payback will be quite long because they are so efficient to start with.
The super efficient ones let you choose the temperature of the water. I set mine to 40 degrees instead of the default 55, to save even more energy.
These use heat pump technology to pull existing heat out of the air and use that to heat the water. They are super efficient, so if you have one stick with it. Although if you need a new hot water system go for solar because that is even more efficient assuming you get plenty of sun where you live.
One problem with all hot water heaters is that they waste a lot of water while you wait for the water coming out to get hot! One neat way around this is a gizmo called the Envirosave hot water saver.
This is an Aussie invented little pump that recirculates the cold water back to your hot water system and only lets it out of the tap or shower when the water is hot. This can save a family of four 5-10,000 litres of fresh water per year!
They cost $200 - $500 fitted depending on local rebates.More details here: http://www.enviro.net.au
So to sum up – if you have an electric or gas storage water heater, you’ll make a big difference to your energy use by upgrading to either solar or instant gas. At the moment you may be tempted to go for solar because Government rebates can make them almost the same price as an instant gas heater. You can get heaps more info at www.SolarHotWaterQuotes.com.au.[Oh – and it goes without saying that you should install good quality low flow shower heads and taps to reduce your hot water demand in the first place – but you already knew that :-) ]
Tomorrow: Find out which electrical appliances you need to do something about, and which ones you can happily ignore