On 30/04/2019 11:14, Martin Brown wrote:
Pessimist! The usual figure for the UK is about 900kWhr per 1kW peak of PV panel which in ballpark terms is about 100W average (taking a year as 9000hr). The further north you go the worse it gets.

Even so I am inclined to think that solar is a bit of a waste of time in the UK since it isn't really sunny enough to be worthwhile. At lower much sunnier latitudes where peak solar power generation coincides with peak aircon demand then having an extra layer on the roof providing shade and solar PV power serves a useful purpose.

Well it's only worth-while because of the very generous subsidy for those of us who got in early, though the price of solar panels has of course dropped a lot since so I don't know whether it's still worth-while.

In our case the predicted outputs were pretty accurate. We've had a 4kW set of panels on our roof since 2011 and the output each year has been at least slightly above the predictions. No real sign of ageing so far - last year was our best year overall. I just noticed the other day that near mid-day we were getting the full 4kW while the sun was out, which doesn't happen much in winter for obvious reasons. So I'm a satisfied owner so far.


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