Also known as solar water heating, solar thermal technology consists of panels that are attached to a roof and used to heat water. Typically, a solar thermal system can produce between one third and one half of a home’s hot water requirements, saving around £80 a year on water heating costs.
In summer 2013 the UK government will make domestic properties eligible for the Renewable Heat Incentive, and solar thermal is currently covered by the Renewable Heat Premium Payment scheme, with a £300 grant on offer to help towards the cost of installation.
How does solar thermal work?
The solar panels convert sunlight into heat energy which is then carried by a heat transfer liquid (either water or anti-freeze) to a hot water cylinder, usually placed in the airing cupboard. From there, the hot water can go straight to your taps, or be stored for later use. It is still necessary to have a boiler for heating water at times when light levels are low, but during the summer months you can expect the solar thermal system to provide almost all of your hot water.
Solar panel types
There are two types of panels used in solar water heating systems.
Due to their greater efficiency during the winter, evacuated tube panels are generally a little more expensive than flat plate panels. Make sure you check with your installer which type of panels are being installed.
How much does solar thermal cost?
In 2013 the average cost of installing a solar water heating system was around £5,000. Costs may vary significantly however; it is a good idea to get more than one quote from installers so that you can compare estimates and choose the best price for you.
How to get solar thermal installed
The heating systems of most homes can be fitted with solar water heating. As long as you have a roof which is facing within 90 degrees of south and a boiler, you should have no problems. In terms of how large the panels need to be, you should have one square metre of roof space per person in your household – each metre of panel area requires between 30 and 60 litres of water tank volume.