We have just installed solar panels on our house in London. We also had panels on our old house in Oxford. How do they compare?
|Panel Size||4000 Watts||5040 Watts|
Obviously, it's hard to compare exact weather conditions - lower temperature makes for more efficient generation - but I've picked a date in April where both sets of panels seemed to have an unblemished view of the sky.
London - despite the disadvantageous placement of the panels - generated 75% of the electricity that Oxford did! That's much more impressive than I was expecting. True, the panels have 25% more potential, and are slightly further South, but I was expecting the split to make things much worse.
I've written some code to graph how the different sides of the roof perform. This means I can see how East compares to West. Naïvely, I assumed that the panels not directly illuminated by sunlight would be basically useless. But nothing could be further from the truth!
Here's the split of the above graph.
Wow! Both East and West generated about the same amount of power - 9kWh.
Given the average UK household uses ~10kWh per day, I could have completely offset my energy use with half the panels!
There are some caveats. Spring is perfect solar weather - long days, cool temperatures, and little tree coverage. Cloud coverage can ruin the generation.
East facing solar panels 🆚 West facing solar panels. London, UK. pic.twitter.com/TB0afpTUX9
— Edent's Solar Panels (@Edent_Solar) March 29, 2020
If you're thinking about getting solar panels, but are worried about your roof's layout - I hope this provides some useful information.
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