We added a solar panel on Campbell’s roof to charge the auxiliary batteries when parked in the sun. Now the refrigerator can run for a longer time between drives.
The DC-to-DC charger for the auxiliary battery incorporates a solar controller, so the electronics were already in place.
The one-hundred-watt Renogy RNG-100D-SS was a perfect fit in the opening. I only needed to drill holes in the aluminum frame and use tie-wraps to secure it to the lower rack rails.
There is plenty of open space and ventilation below the solar panel to cool it during hot days. That is important because the cells become less efficient as the temperature rises.
Since the panel is below the upper rack rails, cargo can also be secured across the top. Sometimes the additional load is needed more than the extra power or removed after reaching a campsite.
We only use the sunroof for ventilation, so we don’t miss the view of the sky. And the panel shields the open rear of the sunroof when it is raised for ventilation.