Solar thermal systems offer the promise of free hot water from the sun, but 10 out of 14 installers exaggerated the potential savings in an undercover investigation by consumer champion Which?

Everest and Ideal Solar Energy potentially broke the law, using dodgy sales tactics and hugely over-stating the potential benefits of installing a solar thermal system. An independent expert calculated such a system would cut about 10 per cent from the Which? household's annual gas bill, but Ideal Solar Energy quoted savings of 50 per cent, while Everest quoted a 43 per cent cut. Everest also claimed the home owner would save £35,000 over 20 years, a massive exaggeration.


Both companies used the classic hard sell tactic of offering huge discounts if the buyer signed up on the day, depriving them of the time needed to make an informed choice.

Not one of the 14 companies tested identified all the important technical challenges before providing a quote, and five provided a quote over the phone without even bothering to visit the property. Just one company, Southern Solar, was found to be helpful and provide sensible advice.

Peter Vicary-Smith, Chief Executive, Which?, said: "Most of the firms in our investigation behaved like true cowboys - they promised huge savings that bore no relation to reality, and some really piled pressure on the homeowner to sign up immediately or risk losing a one off 'special offer'.

"The solar industry is too important to our long-term energy needs for things to drag on like this. It needs to clean up its act, and if it won’t, the OFT and the government will have to step in."

(CD/GK)