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.

How does it work?
For domestic hot water there are three main components:

1	Solar panels or collectors are fitted to your roof. They collect heat from the sun's radiation. There are 2 main types of collector: Flat plate systems which are comprised of an absorber plate with a transparent cover to collect the sun's heat, or Evacuated tube systems which are comprised of a row of glass tubes that each contain an absorber plate feeding into a mainfold which transports the heated fluid.
2	A heat transfer system - uses the collected heat to heat water;
3	Hot water cylinder - stores the hot water that is heated during the day and supplies it for use later.

The benefits
Solar water heating can provide you with about a third of your hot water needs. The average domestic system reduces C02 by around 350kg per year and about £40 a year of your hot water bills, depending on the fuel replaced.

Installation and maintenance costs
The typical installation cost for a domestic system is £3,200 - £4,500. Evacuated tube systems are more advanced in design than flat plate, and so tend to be more expensive. Solar water heating systems generally come with a 5-10 year warranty and require little maintenance.

A yearly check by the householder and a more detailed check by a professional installer every 3-5 years should be sufficient (consult your system supplier for exact maintenance requirements).

Is it suitable for my home?
Solar water heating can be used in the home or for larger applications, such as swimming pools. You will need 3-4 square meters of southeast to southwest facing roof receiving direct sunlight for the main part of the day for a domestic system.

You'll also need space to locate an additional water cylinder if required.

Choosing a system suitable to your needs requires consideration of a range of factors, including the area of south facing roof, the existing water heating system (e.g. some combi boilers aren't suitable) and your budget.

A competent accredited installer will be able to assess your situation and discuss with you the best configuration to meet your needs.