I get a 50% dip in power just by laying them flat vs being tilted. On the north side I'd expect more like 80-90%.. for that reason I'll never do it on the north side of my roofbut is it typically a ~50% dip like I see online?
Thanks. Dumb question, but what's the best way to find my azimuth?You can model expected output of the PV array on each area of the roof with this. Using your address, azimuth, tilt and STC rating of the array.
PVWatts
Estimates the energy production and cost of energy of grid-connected photovoltaic (PV) energy systems throughout the world. It allows homeowners, small building owners, installers and manufacturers to easily develop estimates of the performance of potential PV installationspvwatts.nrel.gov
http://www.solarelectricityhandbook.com/ this site has all of them calculatorsThanks. Dumb question, but what's the best way to find my azimuth?![]()
That looks like Tesla. My advisor was able to share detailed plans that include that info (below, top-right).Thanks. Dumb question, but what's the best way to find my azimuth?![]()
ROI is less important. I just want to get the most production I can for >100% offset. Per PV watts, the 12 north facing panels will produce about 4200kWh/yrAzimuth is the direction of the panel, per the compass.
7 years ago, I installed 32 panels facing south on a separate building. 5 facing south on the house, and one on the house facing east.
I used the NREL pv watts calculator for every array (individually). It came back with 19,500 per year. The numbers I've actually recorded are within 1% of that. It's almost scary accurate.
I don't think north facing panels will pay for themselves in the long run. I would only do it if.....it's not about your return on investment, but about just making 'some' power.