We have just had solar panels fitted to the roof. We're fortunate in that our house faces almost due south and gets the sun at the front virtually all day. But solar panels work on light not just when the sun is visible - which I didn't know until the other day. The maximum we can generate is 2.5kw. Of course it has been cloudy since we had them fitted on Wednesday so we haven't been able to generate the maximum amount most of the time. On Thursday it was quite sunny and I looked at our electricity monitor and it was showing we were using no electricity even though the fridge/freezer was on, two computers were on as well as a pedestal fan and various others odds and ends.
What is even better than the reduced electricity bills in future is that the panels were free and are maintained free for 25 years. It's part of a government sponsored initiative and was done through this company - www.homesun.com Anyone can apply and they will tell you whether your house is suitable without sending anyone out to see it by looking at your house on Google Earth. Not everyone gets it free - though I've no idea how they decide whether you have to pay or not. I know we could have been asked to pay £500 and we were considering whether we would do it if we had to pay. But as it turned out we didn't have to pay.