... Especially as you can literally 'drive around Australia' in an EV towing a caravan on the 'Big Lap'- anything that has a range of more than 250km (and many of these commercial light and medium trucks are 300-500km or more), an EV motorhome would make a LOT more sense...
RV-wise, it gets complicated.
This would work for those who pop off to a local scenic spot for the weekend, or a caravan park for longer. Park and plug in.
For your "grey nomads" however, it's only workable for the well-heeled retiree.
You would need to spend most nights at an RV park and the affordable version of those is rapidly going the way of the Dodo.
For us "off grid" full timers, on a budget... not doable.
Let's say you cram all the solar you can on the roof, likely 1.5kW but we'll call it 2.
That will net you around 7-10 kWh a day into your battery bank.
A large EV SUV today has a ~300 kWh pack, an RV would likely have one a tad larger. Solar alone ain't gonna cut it.
No boondocking EV RV for me, sad to say.
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ETA: Not sure if the towed trailer is better or worse... small tow vehicle but only room for ~600-800 watts of panel on the trailer.
Eta2... And heating and cooling get worse for off-grid all-electric.
You can do some cooling today with efficient mini-splits (or just open the windows.

) but you need to be in a sunny spot and that means needing the AC.
Electric heating at night however... forget about it.
You would have to go propane (a decent power suck for the blower fans) or a fitted/exhausted diesel heater (those are pretty nice I hear).
You're not going to be running a nice 1500 watt resistive wire room heater. That's your whole day's collection gone in half an evening.
I realize I'm being "motorhome" biased, not a trailer guy myself. If I could just go where it a pretty view there's no public charging stations
That said, it can be damn hard getting this medium sized one of mine into half the filling stations... I shudder to think what the reaction would be if one was sitting across eight charging stations for an hour or so... almost every day.
