On 9 Oct 2006 07:46:25 -0700, "Mr Harry" wrote:


Peter Parry wrote:

On 7 Oct 2006 11:48:42 -0700, "Mr Harry" wrote:

Payback is about 6 years..

How do you work that out?

I didn't. It's on their spec sheet.

Must be true then, I have a nice bridge in London for sale if you
are interested.

Maybe you'd care to come up with some figures of your own?

Certainly. A solar panel (the type makes little difference) has an
efficiency of about 30%. With UK irradiance levels and a 2.8 sq/m
panel this amounts to about 1,000kWh per annum which, with gas prices
at 3p/kWh means a saving of about GBP30 per year. Assuming you are
using peak rate electricity this goes up to about GBP100 per year, on
off peak about GBP50.

RM, like many suppliers of these things, appear to be a bit coy about
price but assume it's a fairly typical GBP1,500-3,000 I'm a bit
puzzled how saving GBP30 or even GBP50 a year for 6 years returns
GBP1,500 to 3,000? (If you are on peak rate electric its much
cheaper to opt for an overnight rate than fit a solar panel).





--
Peter Parry.
http://www.wpp.ltd.uk/