I have a 95 watt GoPower panel that came with the trailer, added another 100 watt panel on the roof, & carry a 160 watt Solar Blvd portable. During the summer the roof top panels keep my pair of 6V batteries full, however with the short days & low angle sun in the Winter, adding the portable is necessary. I switched out the GoPower controller for a more adjustable Blue Sky 30, and added a panel mount SAE connector to plug in the portable (I added an additional connector to the portable to bypass the built in controller).