Sun Angle Versus PV Module Orientation.

What is the best angle and orientation for solar panels? That is a question that I am being asked over and over.

As a general answer I will make a bold statement and I can prove it to you. Any roof is a good roof for solar power. Obviously on a north facing roof you will have little to no harvest in the winter, but in the summer it can perform almost as well as south. East and west facing roof planes can be very productive, a little better than 80 % compared to south. There are very simple tools online that can calculate for you your anticipated energy harvest over a 12 month period. https://pvwatts.nrel.gov/ This calculator is pretty accurate and easy to navigate.  

Another cool calculator http://solarelectricityhandbook.com/solar-angle-calculator.html calculates the optimum angle for your solar panels by season.

Watching the u-tube video https://www.youtube.com/watch?v=0esRftZ3qdw will shed a little more light on the idea that south is the ultimate orientation

The idea to mount your solar panels vertical works okay for the winter. However, in the summer it can leave you with tremendous shortcomings. You think you should harvest lots of energy and don’t realise that the modules only start receiving harvestable sunlight by 9:00 AM and start you loosing production by 3:00PM.

But to go back to the original question, the answer south is correct. The best roof angle is the equivalent of your locations latitude.

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