Solar powered, external combustion steam power is the ticket.
Put a black, triple expansion flash boiler in the bed of an F-350, and attach a battery powered gimbals mounted, self-aiming magnifying glass to almost focus the sun on the boiler, since we don't want to burn a hole in it.
A 1,000 gallon water tender trailer would complete the ensemble.
In an emergency, to could even double as a fire apparatus.
Now, if there were just some way to drive it at night....
Just put enough asbestos on the boiler to keep it hot all night.
That's simple. Just add another trailer with an aux boiler running on lawn clipping.
The Stanley Steamer was just ahead of its time.