The cost to install the System was £15,000
The predicted number of units produced was 2700 dropping to 2200 in Year 25
The predicted income per year was £1400 in the first year rising to £1600 by year 25, due to the increase in feed-in-tarrif increasing inline with inflation.
Below i show the first 3 years
Next I needed to see how much i had saved on my Electricity Bill.
From the Simply Switch web site i found information that the Average 4 Bedroom house used 6000 Units a year. But looking at my 2009 and 2010 Electricity I used 4335 units and 4265 respectively. About 12 units a Day and a little over Two Thirds of the Average household. So already i was being cost effective.
Looking at the Electricity Usage for 2012 and 2013 i used 2389units and 2505 respectively. This is about 6.7 units a day a drop of 5.3 So not quite half but a considerable saving. This works out as a saving on my Electricity bill of about £210 a year (and this will only go up as electricity prices increase.
Adding this to the the Fits income for the Past 3 years we end up with a Total of £5000. So I have Paid off a third of the installation costs in the first three years.
Assuming almost no increase it fits(and its linked to inflation) but just enough to counteract the degradation of the panel. The income over the 25 Years would be £41000.
If i invested £15000 over 25 years and had £41000 at the end that would be slightly over a 4% per year Return.
But this in not a fair comparison as that assumes that the whole of the 15K and interest is left invested over the 25years. Where as i have been spending the Money generated. So the true return is closer to 8-9%
*Its important to note now that Installation Costs and Fits Payments have both fallen drasticly and that anyone considering it now should look at Current costs and Fits Payments.