Sue Roaf installed one of the first PV roof in Britain back in 1995.

She was driven to act by her experience of living in Iran and Iraq for 10 years carrying out archaeological digs. She says:
“It didn’t seem fair that the lives of the nomads in the area were being destroyed by the impact of global warming when they were not causing the problem.
“I realised that even a small increase in temperatures could have a huge impact, so I decided to cut my own emissions when I came back to the UK.”
As a result she doesn’t feel that sense of apprehension when her electricity bill drops through her door. “I’ve just had my bill for the quarter and it was just £14.75.”
Sue reckons she saves about £500 per year because of the system, which is far more than when she installed PV in 1995, partially because of the inexorable rise of electricity prices but also, ironically, because of global warming. “It’s producing almost 10pc more power now than a decade ago.”
And with the recent flooding highlighting the potential threat to electricity supplies caused by erratic weather, having your own supply could be a Godsend. “If I was cut off from the grid I would be perfectly comfortable in my home and could survive on the power I produce.”
Read more at: http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/08/20/nosplit/eavolt120.xml