But the whole process is incredibly sketchy.
Tesla does not recommend towing its cars. Whether the battery runs flat or there is some other problem that brings the car to a halt, Tesla says the Model S and Model X should be loaded onto a flatbed.
The concern is that towing will do damage to the electric motors. Indeed, any damage that does result from towing is not covered by the warranty.
But that does not stop carefree Tesla owners from towing their cars regardless. Especially as it turns out that the regenerative braking will recharge the batteries of the car that is being towed.
Norwegian Model X owner Bjorn Nyland put the theory to the test, towing a Model S belonging to his friend Jorgen Winther-Larsen.
Over a drive of 6.6 miles (10.7 kilometers), Jorgen’s Model S gained 7.2 kilowatt hours of charge, while Bjorn’s Model X used 14.9 kWh. Which isn’t especially efficient.
Likewise, a maximum charging power of 28.8 kW was reached, less than half the 60 kW that can be achieved by regen braking. According to Bjorn, the short length of the tow rope meant they could not go fast enough to reach that level.
The video above shows shots of both cars’ data readouts during towing.
A Russian Model S owner tried the same experiment, having roped his car to the back of a semi-truck. Which is not at all sketchy.
It should be noted that the maximum towing weight of 5,000 pounds (2,268 kilograms) that a Model X can manage is less than curb weight of a Model S. But that has more to do with suspension loadings, which aren’t the same when towing something that is not rigidly connected.
Anyway, towing should clearly not be relied on as a way to recharge a Tesla’s batteries. It is too inefficient and risky. It is an interesting experiment, though. Like Bjorn’s tests of the Model X’s door sensors.