Panel elevation

BarryFields

If I had two identical panels, wired in parallel, feeding a common MPPT controller. Both in fixed positions.

Both panels are oriented dues south. One has an elevation of 45 degrees (winter) and the other at 30 degrees (spring summer fall).

Will the MPPT controller choose a "reasonable" compromise MPPT point?

BB.

Don't know... Depends on the controller and their software...

Instead of "one peak", you could have three (lesser) peak power locations. The "hot panel" (one directly facing sun) will have lower Vmp. And the "cooler panel" will have a bit higher voltage. Which "power peak of Imp * Vmp = Pmp" the controller/software picks may be a "local optimum" or the overall best optimum operating point.

Without testing, it is difficult to know.

MPPT will work best if the panels are all on the same plane/direction. I usually start with panels tilt = latitude of the location. That will, on average, collect the most Watt*Hours per year.

If your loads are relatively constant over the year, then tilting for best winter harvest (when you have less hours of sun per day)--Then as you get into summer, you will be harvesting more power than needed anyway.

Use a solar radiation calculator and see if the winter/middle/summer tilts really make a huge difference or not:

http://www.solarelectricityhandbook.com/solar-irradiance.html

Generally you design an off grid system to (on average) harvest 2x or more energy than you really need. This allows for a few days of bad weather, aging batteries without needing backup power/starting a genset more often.

-Bill