“Investment in solar will be a formidable source of renewable energy.”
Only when it is cost effective without taxpayers subsides. At present we are all paying for renewable energy products via our fuel bills / tax. So when the salesman comes knocking and say's "you can get a Government grant" what he's really saying is, is that it is being funded by everyone and will continue to do so for the forseeable future.
“Also consider that the UK Government plans to reach a renewable energy goal by 2020.”
The plan is a legal obligation otherwise there will be financial penalties. What I find funny, is that the majority around 90% of renewable energy products are imported from none other than both China and the USA which kind of makes a mockery of the green issues altogether as all they've done is stick 2 fingers up to the whole idea with China laughing all the way to the bank. And as for electric cars, the production of them alone prevents them from ever being green.