Goodyear's Concept Tires Harvest Heat To Power Your Car

In the world of electric cars, efficiency is king — wasted energy is just more miles you can't travel. While regenerative braking is old news, regenerative tires that use heat and vibration to recharge the battery would be something completely new.


That's the concept that Goodyear introduced at the Geneva Auto Show this week. The tires — which are very much still a concept, and barely a twinkle in the manufacturer's eye — would harvest heat from several different processes, and then feed that back into the batteries.

At the core of the concept is a layer of piezoelectric material underneath the rubber of the tire. Piezoelectric materials can generate electricity from the application of mechanical force, but in this instance, the (non-specified) 'thermo-piezoelectric' material takes excess heat from the outside of the tire and converts it into electricity.

The heat comes from the friction of the tire on the road, the sunlight acting on the tire, or even just the vibration and bumps of driving along the road. It's unclear how much electricity these magic tires would be able to regenerate, or how much the techno-magic tires would end up costing. But at least it's refreshing to know that the tire companies are still thinking way, way outside their rubber-lined boxes. [Goodyear]



It's unclear how much electricity these magic tires would be able to regenerate

Hint: probably not enough to recover the cost of this added tech.

There's an un-ending desire to recover "waste energy," in many applications. While this is a good exercise to undertake, one needs to remain cognizant of the perpetual motion trap that often hides in these ideas. In this example, setting the costs of the added technology aside, how much impact is made to the efficiency of the rest of the system? Does the rolling resistance increase? Does the energy recovered offset the added mass that needs to be carried along? Is this akin to strapping a small wind turbine to the rear bumper to capture power from the turbulence of the car displacing air as it moves? (not quite, but I hope you begin to see where I'm going with this)

While indeed there is some level of energy that can be recovered, what point is it on the curve of diminishing returns?