Some guy who lives by me dad has been using solar panels to provide his electric since the late 1990's and actually makes enough during the BST months that he sells some electric back to the national grid.
Overall though, he is only just starting to save money, due to the initial cost of the kit and installation etc.
It would be cheaper to buy nowadays and the government will offer subsidies to help pay for it. Its worth it in the long run for sure, but for most people, its the short term cost that continues to put them off.
Its also not helped by the fact that there is many con men trying to sell it and the industry is beginning to gain a somewhat dodgy reputation.