[.:4:.]

What about a petrol generator to plug into the shore power van inlet for 240v stuff, and use the 12v for lighting? On site at my old job we would use a portable honda genny to power lights and things like power tools and it was quiet and wouldnt use much fuel over 12 hours of getting worked pretty hard. So you'd only really need to run it when you need 240v. If the stuff like lighting is 12v, the battery can do that, also if say you have an overcast day and a solar setup wont charge the battery, a 240v battery charger could be used.