On Jun 10, 11:34*am, tony sayer wrote:
No I don't, but two people who I do know have them, and both have said
if they had to pay the full price for them they've never have bothered
with what they'd get back..

Output is reduced in overcast conditions not zero.

Yes quite thus far this year;!...

Actually up on last year. The next three months are the critical ones.

Are you saying we have had more hours of sunshine this year compared
with last year?..
--
Tony Sayer

So far yes.
But they work significantly more efficiently when it's cold so that's
another factor, The cold North winds we have been having. Also I am in
the lee of mountains, the Fohn effect reduces atmospheric moisture
(clouds)