Unless you are very decided on when you will be where I think it's a bit odd for someone to tell you a genny will not be needed. Far enough from the equator in the wrong season and solar won't do much so are they suggesting you sit for an hour or two with the engine running to recharge?
Also, are solar panel sizes fixed already? If not, just consider you could shunt rooflights and or other roof furniture to better accommodate "more"
Also, will there be any allowance for various international mains hook up?