Solar water heating systems use heat from the sun to work alongside your conventional water heater. The technology is well developed with a large choice of equipment to suit many applications.
Benefits
Can provide almost all of your hot water during the summer months and up to 50% on an annual basis
Reduces your impact on the environment - the average domestic system reduces carbon dioxide emissions by around 400kg per year, depending on the fuel replaced
Different types of system
What best suits your needs depends on a range of factors, including the area of south facing roof, the existing water heating system (some combi boilers aren't suitable), and your budget.
A competent professional installer should assess your situation and discuss with you the best configuration to meet your needs.
Flat plate collectors are more common in the UK. The more expensive evacuated tube collectors offer an alternative; they are more efficient and take up less space.
How it works
These systems can provide around one half of the annual energy demand to heat your hot water.You will still need your existing hot water system to provide the rest.
For domestic hot water, there are three main components: solar panels, a heat transfer system, and a hot water cylinder. Solar panels - or collectors - are normally fitted to your roof. They collect heat from the radiation of the sun.The heat transfer system uses the collected energy to heat your water.The hot water cylinder stores the hot water that is heated during the day.
Is my property suitable?
Preferably you will need 2 - 4m sq. of south-east to south-west facing roof receiving direct sunlight for the main part of the day.You'll also need space to locate an additional water cylinder if required.
How much will the installation cost?
A system using 4m sq. of flat plate collectors is normally in the region of £4,000. The more efficient evacuated tube systems will take up less space - usually around 3m sq. and can sometimes be fitted for the same price as flat plate panels.
How much will a system save?
If you currently use gas to heat your hot water, you could save up to£45 per year. If you currently use a more expensive form of energy, such as LPG, the annual savings will be much higher.
How much does a system cost to maintain?
Solar hot water systems generally come with a 10-year warranty and require very little maintenance. A yearly check by the householder and a more detailed check by a professional installer every 3-5 years should be sufficient.
For funding and advice contact the Low Carbon Buildings Programme (LCBP):
Tel:0800 915 0990 or visit www.lowcarbonbuildings.org.uk
