But the plight of the EV owner may now be at an end. Long before Elon Musk completes his grid of battery-swap Tesla stations, this little trailer could free EVs from the plug. Called the EP Tender, the trailer is essentially a generator on wheels. A cable, running from the EP Tender to the car, detects any "low-battery" warnings the EV might give off. Once a warning is detected, the generator switches on and feeds electricity to the starving batteries.
The generator inside the EP Tender is capable of putting out 22kW of energy while traveling at 80 mph. That's enough juice to extend the range of some EVs by as much as 360 miles.