My brother was into Tesla very much, but he needs AWD with extended range batteries. The quote was in $90,000 and I think that was after taxpayers "contribution"
Hybrid buses who runs on the mentioned principals (less solar panels) are on the roads for more than 10 years.
Yosemite is using them exclusively in the Park.
But the idea is that electric motors are build into the wheels and small generator runs at constant speed all the time. Diesel engines love constant speed and this way also save fuel.
So when the bus starts, it takes most of the power from battery pack. Since city/park buses don't drive fast - energy requirement is not that big.
Than when the bus stops after short drive, there is energy recovered and small generator has time to catch up with battery charging.
This will not work with big motorhome that needs about 300HP to keep 70mph all the time.
Technology those days bring new revolutions every day, but I think it will take a while before we can fit 225 kW of solar panels on motorhome roof.
