A very good practical solution is the charge the batteries each morning with a quality quiet generator such as Honda EU2000i.
https://powerequipment.honda.com/generators/models/eu2200iSome people may think solar panels are better and more affordable, but if one does a breakeven analysis the cost savings for solar panels may never materialize for most of us. It depends on how many hours the generator is actually used each year.
Here is a link to Solar vs Honda financial breakeven analysis that will help determine which source of power is cost effective.
https://www.nroa2003.com/download/Miscellaneous/Cost_of_Solar_vs_Honda.xlsOf course the breakeven analysis for carbon emissions is a different story all together. At what point does the accumulated emissions from the generator's manufacture and operation match that of the solar panel emissions? If we take a page from the BEV's breakeven analysis, then it probably is several years away for heavy RV users and probably never for the occasional weekender.