By my calculations, had we been in one of those electric buses, our 3-year tour of Oz would have taken about 10+ years.... IF there were charging stations in places like Uluru and the Bungle Bungles!

Every caravan park is a charging station if they offer powered sites. Most CP's these days only offer powered sites so you don't get an option. I know many hate caravan parks and I don't blame them, I'm not terribly keen on them myself. They do provide that back up recharge, a place to dump waste, top up water, do the washing even if it is your own machine and have that long shower you can't have when traveling. The 15 amp power point will supply 3300wh x the number of hrs you are plugged in, a 24hr stop will put just short of 80kWh back into the battery, add the solar @ 3kW x 5 hrs and in a 24hr stop over you have added at least 250kms range to the battery pack. Add to that, all the time you are driving, as long as the sun is shining, there is another 15kWh going into the battery every day.
That is gradually changing as the diesel gen sets reach the end of their service life. Many are looking at changing to solar/wind/battery with the diesel genset as a back up plan. Some are even going geothermal combined with solar thermal, I believe the Olympic Dam project is looking into or may have even committed to upgrading their power generation to this method. It appears Whyalla will be wind/solar/battery powered in the near future, but then the South Australia grid is anyway.
No more needing 2 OKA's to tow you out at Taggerty
I'd look after it for you Peter, drive you around in it sort of like "A weekend at Bernies"