On Monday, February 25, 2013 10:28:21 AM UTC, Ken Cook wrote:
Hi, All,

I'm thinking seriously about installing these PV panels and am looking for
advice. I have a feeling there could be some expertise on this ng. I
estimate about 2,200 kWh per annum for Copley from available data on the
web, although the installers that I have quotes from reckon a touch more
(believe it or not!)

I hope to wire the immersion heater through them and use as much as I can
rather than export. I have until April to decide as the FIT payment is
reduced again then.

I am thinking of a 3kW system. Does anyone out there have them? Are they any

good overall or are they a con?

Any guidance much appreciated.

Ken,

I have 1.5kw system. The production over the last 2 full years has been 1445kwh and 1317 kwh respectively (last year only saw 88% of normal sunshine). Providing a total feed in tariff of £1160.

It's not a case of wiring them into an emersion heater. The panels generate DC which goes into an inverter. The AC voltage is then output from the inverter marginally above the mains voltage, so your electrical system prioritises the home production for use. Obviously it makes sense to use the washing machine etc. when the sun's out.

With a small system, it is normally assumed 50% is used on site, so you get an additional (though small) income for exporting 50%, £43 in my case over 2 years.

Adding in what I'm saving on power, I should get my money back in Approx 9 years (I have a spreadsheet I can email you if you wish, which also allows for a return on investing the money I spent.) Savings over the last 2 years have been
£1160 - FIT
£ 43 - Export
£ 115 - Est bill saving on the home use portion
£1318 - Total

My panels were installed by a local firm who have also done many schools etc in Cornwall, and the Eden Project. NO good to you but their website is excellent in explaining things. My home on their site http://www.plugintothesun.co.uk/case...e-in-penzance/

Word of warning. Apart from the fact your sunshine totals are significantly less than mine, I also get reflectio off the sea. Anyone who regular visits the coast will know how much the light increases on a brightish but cloudy day near the sea. My panels often generate 600w under thinish Sc, you'd get nothing like that inland. Also, the winter angle of the sun at your latitude beccomes more of an issue.

There are maps on the WEB (somewhere) which show approx annual generation per kw of panels over England. Your area is a good 30% lower than the south coast of Cornwall.

Email me if you want more info

Graham
Penzance