2070 Watt of solar panels
A total of 13 SolarWorld XL 345-Watt panels are mounted on the Motorhome and Trailer. Anything from 6 panels (2070 Watt) to 13 panels (4485 Watt) can be used for charging the house batteries. Through two MorningStar TriStar MPPT-60 controllers can a total output of 120 Ampere charge the battery or run loads.
The SolarWorld XL 345-Watt is a 72 Cell panel and is 6.8′ by 3.4′. The large size and the 50 pounds weight of each panel prevent tilting the panels for better winter performance. The panels are mounted above the roof of the Motorhome and the vent can be partially opened underneath. The 4″ air gap also ensure the panels stay cooler and more efficient. The rails used is Ironridge XR-1000 that is traditionally used in residential solar systems.
The internal ceiling temperature can be up to 6 Fahrenheit lower under the panels compared to roof exposed directly to the sun. So we always park partially in the shade from our own solar panels.
All Solar Panels are wired in parallel for 35-40 Volt, with all panels in parallel can any number from 6 to 13 panels be used. The wiring of the 6 panels from the roof is through dual 8 Gauge solar wires directly to the electrical room. The panels mounted on the trailer can be switched around and the power is transferred as DC with a 6 gauge wire from the trailer that can be disconnected with an Anderson connector.
Dual MorningStar Tristar MPPT-60 solar controllers handle the incoming solar power to charge the house battery. Each controller is limited to 60 Ampere output that is 1450 Watt at full charge. The solar panels can provide more than that in the best scenario, but during the summer when the sun is high and the days are long is the time maximum output current is a limit. The MPPT controllers can handle many times the solar capacity compared to maximum output capacity, the solar panels are controlled to only provide the power that is needed for maximum output.
The MorningStar controllers are passively cooled and that is important in an electric box that can get very dusty when driving on dirt roads. Two additional fans circulate air in the Electric Box when the temperature exceeds 100 Fahrenheit.