From my experience in aircraft design when ever a new piece of equipment is added to the existing airframe it adds a lot of weight because the surrounding airframe has to be beefed up to support the added item. However when the paper is blank the required item like an antenna for example can be integrated in the the structure for a lot less weight. So an antenna can be part of the structure, be an antenna and a grab handle all at the same time. Having said all that I think the only way that an electric RV can save weight is to integrate the batteries and other electrical stuff say into the initial design of the box beam frame for example or making the RV shell where the outside layer of fiber glass is replaced with a bonded on solar panel film thus reducing the over all weight. I don't know enough about solar to understand if the panels are getting more efficient as a function of time like Moore's Law in electronics or not. I know cost has come down over time has the efficiency improved also? If so can solar add much charging to the batteries to make it worth while in 5 years? 10 years? any years?
