the second year

Here are our figures for the calendar year  2011. We generated 3966 units, imported 2588 units of electricity and used 383 units of gas. Our best month this year was July with 475 units generated, our worst was December (grey and rainy even by December's standards) with 111.
I hope this helps with your planning if you are considering investing in a system.

After one year

Here are our figures at the end of the first year...

We have generated 4250 units of electricity.

We have imported 2773 units (mostly in the evening and at night), saving us 1301 units compared to our average old import over one year.

We have imported 550 units of gas (saving about 150 units a year)

Things we have learned...

This is 'easy green' to implement.

Even is you don't care for the planet two hoots (we do care!) you can reap a return on your investment.

Without going overboard and getting stressed about it, you can make small changes to minimise your import - we are trying now to use the washing machine and bread-maker during the day (no cost electricity). To aim to run machines sequentially rather than switching them on all at once. We have bought a slow cooker to sometimes use the trickle of electricity that is generated in the daytime rather than importing a high energy load when turning on the oven in the evening.

We think we will be a net zero bills house. The income from the Feed In Tariff will cover the imported electricity gas and water bills......now to work on that dreadful council tax bill - ideas anyone?

Reached a landmark 4000 units this weekend - after just 11 months on stream :)

Output Figures

Month - My guesstimate before installation - Actual KWh 2009-10, 2010-11 

November - 142 - 168 - 203

December - 100 - 162 - 141
January - 111 - 156 - 151

February - 214 - 170 - 170

March - 354 - 371 - 421
April - 444 - 560 - 520
May - 478 - 496 - 475
June - 462 - 573 - 450
July - 464 - 450 - 475
August - 456 - 423 - 400

September - 367 - 374 - 374
October - 221 - 323

My shiny roof

We found it hard to find figures for PV output, month by month so we thought we would share our figures on the web. Hope this helps those contemplating installing PV.

Good luck.

We have a 3.96KWp array installed on a south facing 35degree roof, with no shading. Installed by SunGift Solar on 16 November 2009.

We have 22 x Sharp NU180 panels and a Fronius IG40 inverter.