"Dave" wrote in message
...
On 24/05/2011 19:19, TMC wrote:
Some one I know has been offered a solar panel deal

The information I have been given is that the panel installation would
normally cost 10k

At that rate it would pay for itself in ten years due to a combination
of electricity not paid for and inconme from the excess going into the
grid they say

They are offering the panels for 250ukp and say that they make their
money by taking the money from the excess going into the grid

My current electric bill is about 80ukp per month

How big would the panels need to be to generate in excess of this usage?

I cannot see how this could ever work so can some one please explain

Don't solar panels generate DC?

How is this fed back into the N grid?

They feed a ~£1k DC-AC converter that synchronises to the grid.

It also cuts the feed if there is a power cut, they don't want their works
getting a shock if they are fixing cables and have turned the feed off, i.e.
you can't use the panels to provide power in a power cut with the standard
installation.