How to buy solar panels How to buy solar water heating panels

Solar hot water heating panel

Solar water heating systems qualify for the Renewable Heat Incentive

In this guide you'll find how much a solar water heating system costs, how to get financial support, how to avoid dodgy salespeople and how to find a reputable installer. 

Solar water heating costs and savings

Solar water heating panels typically cost between £3,000 and £5,000, and will potentially save you between £65 and £125 a year on water heating costs. There are bigger savings to be made if you're currently using LPG to heat your water.

Solar heating systems qualify for the Renewable Heat Incentive (RHI), which provides quarterly payments over seven years for owners of solar heating panels.

Solar water heating and free cash

The RHI is a government scheme that pays consumers for generating heat by using renewable energy.  

We recommend that you first make sure your home is as energy-efficient as possible, then think about which types of renewable energy technology – including solar panels – might suit you. There are two reasons why you should first ensure your house is energy efficient:

  • The more energy efficient your house is, the less heat you will lose and therefore the less heat you will need to generate in the first place. This means that you should require a smaller heating system, cheaper to purchase up front and cheaper to run in the long run.
  • To qualify for the RHI, which pays you for having renewable heat, you house will need to meet minimum energy efficient standards.

You can find out more about RHI in our guide to the Renewable Heat Incentive.

Video: Which? investigation into solar water heating sales

We went undercover in 2010 to investigate solar water heating companies and posed as householders wanting to buy a system. In our probe, 10 out of 14 companies exaggerated the potential savings. 

Here's a clip from our undercover video of the Ideal Solar Energy salesman in action. Identities have been disguised to protect our researcher.


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Solar water heating sales tactics

Here are the key points from our investigation:

  • Everest and Ideal Solar Energy potentially broke the law, using dodgy sales tactics and hugely overstating the potential benefits of installing a solar thermal system. 
  • An independent expert calculated such a system would cut about 10% from our householder's annual gas bill, but Ideal Solar Energy quoted savings of 50%, and Everest quoted a 43% cut. Everest also claimed the homeowner would save £35,000 over 20 years – a huge exaggeration.
  • Not one of the 14 companies tested identified all the important technical challenges before providing a quote. Key checks they missed included inspecting the roof from the ground, inspecting the existing gas boiler, the cold water tank in the loft and the hot water cylinder, and checking the water quality and whether the washing machine and dishwasher could use solar-heated water. 
  • Five gave a quote over the phone without even bothering to visit the property. Just one company, Southern Solar, was helpful and provided sensible advice.

Finding a good solar company - things to look out for

Our investigations showed some salesmen using dodgy sales tactics and exaggerating the financial savings that could be made, so we strongly recommend that you do your own research first. Then compare the estimates of costs and savings you are given by salesmen against other sources of advice.

There are many solar panel installers out there, so we recommend that you always collect a range of quotes to compare. Which? members can find solar panel installers recommended by other members on Which? Local, or search for a certified installer on the Microgeneration Certification Scheme website.

Not yet a Which? member? You can trial Which? for a £1 to get instant access to all of our online reviews.

Solar water heating installation

Before you install your solar panels, find out more about whether you need planning permission and how to make a system more efficient - see our guide to installing a solar water heating system.

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