This short video from Advanced RV showing development and testing of a Volta 48V system may be of interest. In this case getting rid of Onan-type generator doesn't mean going without electric power, or having to rely on limitations of solar power.
Advanced RV went all-electric and got rid of propane too, but that's a separate decision -- although easier to make because once you have all that power available it's easier to justify going all-electric, at least for a small van that doesn't need that much heat or hot water.