Thor Forums

[Bob Denman]

Originally Posted by Chance

I’m no solar expert, not even close, but will say that for the typical RV installation it is indeed unrealistic to expect 100% of panel rating. Most RVs install panels flat on roof which is most practical, whereas the “ideal” rating tilts panels so they are perpendicular to sun. Depending on where you are in US, and time of year, that accounts for a significant power reduction.

Systems “may” also have enough voltage drop in wiring from panel down to controller that it becomes significant. Because you are working with low voltages and high currents, any voltage drop due to resistance in wire becomes a larger percentage of the power being transmitted through wire (compared to what we’re used to seeing).

Also, the sun doesn’t always shine with same intensity. Just because it looks sunny, it may not be as intense as what was used to rate the panel. This obviously also depends on where you are — further North usually less solar power from sun.

I have no idea what your system is, or where you did your test, but in general I'm impressed you are getting 450 watts out of 600-watt rating. Obviously my comments assume you did a typical RV installation with panels mounted horizontally.

This is Chance...
Thanks for chiming in at the exact right time!