Usually, 200 to 400 watts of generating solar cell panels will be sufficient to recharge the RV's batteries (assuming the sun shines). While 200 watts would be the minimum for basic power needs, including LED lighting, propane refrigerator electronics, and a radio. Add a television, more lighting, and other electrical needs; and. We will list all the components next, but first you need to understand the basic system. Solar cells are outside enjoying the sunshine. Wires carry the power to a charge controller located in your RV. Then the wires run from the. This is where you balance costs with performance. A 200-watt system can be completed for under $300. We chose higher efficiency components, but still kept the cost under $400. If not done earlier, now it's time to review the charge controller's operation manual. Plug in the solar panels and start powering up the motorhome's. Our completed goal is to keep it simple and easy to use, so we kept this in mind when we went to work. First, we wanted to make the solar panels.