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New Concept Tire Could Recharge Car Battery
randomErr writes Goodyear Tire showed off its new BH03 tire that can partially recharge your electric car while driving. At the 2015 Geneva International Motor Show a new concept tire was displayed that uses heat generated while driving and converts the thermal energy to electrical power. The triple inner tube design changes pressure to maximize electrical output while adjusting to the road conditions.
The friction from the road generates heat, which is converted by the tire back to electricity, which runs the car!
The faster you go, the better the mileage you get! In fact, cars like these can achieve near-infinite mileage! (YMMV.)
What's not to like?
[clicks on link]
Rats.
I have to assume that any actual engineers at Ford understand Carnot efficiency, and that this is simply an effort on the part of marketing to generate social-media buzz. It's depressing, but not surprising, to see that they're succeeding.
https://www.youtube.com/watch?...
This Russian fellow ran short of battery reserve to reach home so he hooked his Tesla up to a truck. Besides getting a tow towards his destination, you can see that the car is charging the battery at 60 kW rate!
In Russia, car charges you!
I don't read your sig. Why are you reading mine?
Making electric cars even more expensive will really help them get market penetration.
It will never work. It's not 3D printed, using the internet of things, or an Elon Musk company. How can it expect to succeed?
I realize this "tech" is designed for electric vehicles but if you had the ability to convert heat into a meaningful electrical source you would start with the exhaust system of a standard car and do away with the alternator. If they can't do something with that rather significant and easily accessible temperature differential (+300F) I am pretty dubious about them utilizing the relatively minor temperature differential (~30F) of tires.
$1200 for tires?!
No. $1200 for A Tire.
You too can have the same experience as the USAF when their $85 million fighter is brought down by a guy with a rifle. Except it will be your $1200 tire flattened by a $0.0006 roofing nail. Same principle though. Welcome to the firstworldproblems club. Hope you brought that black AMEX card.
Uh, what? In theory, a car would go any distance at constant speed ignoring air resistance and friction except the curving of the earth as it's not really a straight line. But in the real world, you will have friction against the ground and that will generate a lot of heat. Part of that heat can be converted into more engine power. Unlike regenerative breaking you're not adding a resistance to the wheel, you just siphon off what's already happening. Sure if you could reduce friction that'd be nicer, but physics get in the way and you'd rather have some grip to be able to change direction. So it's energy you need to spend, but you don't have to let all of it go to waste.
Live today, because you never know what tomorrow brings
Any electrical energy this produces would be ultimately derived from the car's motor. (unless you push the pile of crap off a cliff) This means if you add devices to resist flex and convert that energy into electricity you are increasing roll resistance and adding load to the cars motor. Plus, you'd have to have a complex slip-ring connection to get the electricity from the wheel to the stationary part of the car. Absolute crap!
What about a windmill on the roof! The windmill spins as the car drives, and produces electricity to charge up the batteries. Modeartors: Please mod this comment up as 'funny'. And if you dont get why, mod it up as 'insightful', then dont moderate slashdot anymore.
don't cut it off www.mgmbill.org
A theory that ignores friction isn't especially interesting in this context.
Rolling friction is a pretty small contributor to energy loss for a moving car. Of this initially small amount of lost energy, some heats the road, and some heats the tire. As someone else observed below, the change in tire temperature is typically around 30 F, or 15-20 C, much less than a 10% change in absolute temperature. That means that a perfectly efficient heat engine could reclaim at most 10% of the thermal energy from the warm tires. In practice, the efficiency would be lower still.
Here's an infographic breaking down energy loss for an internal-combustion vehicle. Even if we assume that the electric vehicle has zero engine loss, rolling friction still represents at most maybe 20% of your energy loss. That means that you'd be reclaiming less than 2% of your total lost energy. In practice, considering the efficiency of the recapturing engine, it would probably be well under 1%; considering the added weight and mechanical loads of the recapture equipment, you might well end up losing net efficiency.
I'm not an engineer, but I have a basic understanding of thermodynamics. This story appears to be pitched at people who don't. If the engineers behind this want to convince people who know anything about physics or engineering, they're going to need something a lot better than this press release.
They only need to convince people who already made the very uneconomical decision to buy an electric or hybrid.
Again? Your sound like a broken record. Anyway, buying _any_ new car is uneconomical, so you are left with no point whatsoever.
The Geneva Motor Show has always been full of stuff that looks cool but can't possibly work. "Concepts" which are nothing more than bad sculpture. It is neither engineering nor art.
The turbocharger doesn't extract energy and turn it into shaft power. The turbocharger uses energy in the exhaust to spin a compressor (aka turbocharger) which shoves more air into the engine, which lets you burn more gasoline. That's where the power comes from.