Solar thermal - Hot water from the sun and you'll get paid for it!

Solar thermal water heating works via solar panels installed on your roof, but instead of generating electricity as with solar PV panels, solar thermal generates energy from the sun specifically to heat water.

The panels can be used in accompaniment with either a conventional boiler or an immersion heater which you can also use when the solar panels are not generating energy.

Solar thermal energy is available throughout the year. A solar thermal system should heat most of your water from April to September, although you will need your conventional boiler or immersion heater during the winter when sunlight is reduced.

As with solar PV panels you will need at least 5 metres of roof space which is south or south-east facing in order to receive direct sunlight for the main part of the day.

Most current boiler systems are compatible with solar thermal, but if you currently have a combi boiler without a hot water tank, this may not be the case and you will have to install a hot water tank. A competent installer will be able to advise you on this.

Benefits of solar water heating

• You will be able to make a considerable saving on your heating bills.

• Cuts your personal carbon footprint.

• The running costs are minimal after the initial installation costs.

• Provides your household with hot water all year round.

• Grants are available to domestic customers through the Renewable Heat Premium Payment scheme prior to the launch of the Renewable Heat Incentive in 2014.

Two types of solar thermal panels

Solar thermal panels come in two forms – flat plate collectors and evacuated tubes. While flat plate collectors look more like traditional solar panels, evacuated tube collectors feature a line of tubing attached together. They require very little maintenance and should come with a five or ten year guarantee.

Costs and financial incentives

Expect to pay at least £4,800 for a good 2 kW solar thermal system , this will enable you to make savings of around £55 per year if you currently have gas heating or £88 per year if you rely on immersion heating.

Solar thermal panels qualify for financial incentives under the government’s Renewable Heat Incentive (RHI) which is introduced for domestic households in 2014. The RHI aims to encourage the uptake of renewable energy and should generate incentive payments of around £400 per year.

Your solar thermal system should be installed by a competent MCS (Micro-generation Certification Scheme) registered installer in order to be eligible for RHI incentives.