The estimated annual output from the installers was 2318 kWh. The actual figure was 3100 kWh. Around 30% more than the estimate. I suppose this was down to the panels being specifically designed for higher latitudes like the UK.
The 3100 kWh offsets 1.68 tonnes of carbon, saved us money on our electric bill (about £150), and provided us with a healthy income from the FIT payments (over £1300).
At the current rate, the panels will pay for themselves in just 4 more years. That is more through luck than judgement on my part: We got the panels in the period when everyone thought the government had halved the FIT payments. Consequently, we got the panels at a big discount (30%), and then found ourselves on the full FIT rate when the government had to drop the cut because it was unlawful. If it hadn't been for all that, it would have taken as much as 12 years to pay us back.
Here's how the system performed over the year:
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| Month by Month Stats |
As you can see from the pie chart, there were 7 months of really good generation (March to September) when we could have the dishwashers or washing machine on without it costing a thing; 3 months (November to January) of low output, and two (February and October) that were in between but still useful.The panels have been no trouble at all (touch wood!). No failures, no cleaning required (They're self-cleaning), and they've survived several storms without being damaged or blown into the next county.
I'm looking forward to seeing how they do in a good year!
