Ian and Judy,

This is a very difficult question to answer since the truth is that it depends on your personal preference and the energy goals you are trying to accomplish using solar panels. We are in the process of adding solar. We are adding an arch since we felt this would make the most suitable location. When faced with how many panels’ or how much wattage to add, our decision was to add as much as the arch could take (without being obnoxious). Our decision was to add the arch first and then measure to add as much solar as we could. It is because we live on the boat and cruise full time. We also have an wind generator. We still plan to run the generator at night with AC units running to cool down the boat for a couple of hours. Even, with us adding the solar, we realize we will not be totally using free energy. We could have perhaps added the solar panels to the rails and accomplished the same, but we like the idea of the panels being out of the way. Our thought (for a full time cruiser), if you are going to add solar, go big.