You can read an updated version of this article here
Recently a number of companies have started to offer to install solar panels on your property for free, life has taught me there?s not much worth having if you don?t have to pay or work hard for it so what?s the catch?
Basically by having someone install your panels for free you give up your right to claim the feed in tariff for the electricity the panels on your roof generate, you will benefit from some savings on your energy bill which for a typical 3 bed semi would be in the region of £200 – £250 per annum, the company who pays for the installation would get a benefit of between £800 and £1000 per annum from the feed in tariffs.
I would also look closely at who is responsible for the roof where the panels are installed ? the panels and the feed in tariff last for 25 years. If its your roof and your panels its clear cut who is responsible for what.
An article in the Guardian explains that even if you have to take out a loan to pay for the panels yourself you will still be better off financially than having a company install them for free.
Link to article in the Guardian: