Humans are not naturally efficient beings. Despite our best three-cups-of-coffee, getting-things-done intentions, we meander, we forget, we waste. And in the aggregate, all these tiny sins—leaving the lights on, turning the air conditioning up, buying too much food at the grocery store—make us use more energy than we need to. Case in point: Drivers know somewhere in their brains that driving with tires at the proper pressure saves gas. But when was the last time you checked the pressure or reinflated them?
Sure, there are the super-humans among us that never forget about things like this. But most of us aren’t, which is why the U.S. Department of Energy gave Goodyear $1.5 million this month to work on tires that monitor their own pressure and inflate themselves.
The idea of self-inflating tires has been around for decades. Many military and commercial trucks already have systems in place to monitor and adjust tire pressure. But these system are built into the underside of massive trucks to monitor all of the vehicle’s tires at once. Goodyear’s technology would make each tire master of its own pressure. All components of the system, including a tiny pressure valve, would fit inside the wheel.
The government money will fund the development of commercial tires using this in-wheel technology. Goodyear also received a grant from the nation Luxembourg, where it maintains a development plant, to work on a model for consumers. Cars do tend to have pressure monitoring systems that alert the driver if pressure drops dangerously low, but until now, the only consumer vehicle that’s had self-inflating tires has been the Hummer (which needs all the fuel efficiency it can get).
On the other end of the transportation spectrum, bikes may soon have self-inflating tires, too. A San Francisco start-up called PumpTire is looking for Kickstarter funding to help commercialize tires that never require inflation. Although keeping your bike tires properly inflated doesn’t save gas, it does make bike riding a much more pleasant experience. Anyone who’s ever ridden a bike with under-inflated tires and then tried it again once they were pumped up understands instinctively that full tires require more less energy to drag across the road: riding across the pavement feels as easy as skating across the ice.
The technology behind the self-inflating bike wheels is easy to understand (Goodyear has yet to explain how they plan to create car tires). Air from outside moves through a valve and into the tube on the exterior of the tire. As the tire passes over the road, the air is squeezed out of the tube and into the tire. The valve measures when the tire reaches the proper pressure and then shuts off. No more air can get in until it’s needed.
Biking is full of small hassles, and keeping tires at the proper pressure is one of them. If self-inflating tires can eliminate one hurdle that keeps people from biking regularly, they could save gas just as efficiently as self-inflating car tires in the long run.
