Goodyear Electric tires!

[speedmd]

Goodyear announced tires that charge your EV while you drive http://www.roadandtrack.com/car-cul...year-tires-change-shape-generate-electricity/

 

[amberwolf]

Not quite a new idea, though I don't recall an implementation like that. I doubt it would be able to generate anywhere near the kind of energy needed to "eliminate range anxiety", however, because that energy it "generates" is actually being recovered from the energy used to move it, and is almost certainly much less than even minimal regenerative braking, even over time/distance of a full trip vs the few seconds at a time of stopping.

Since regen doesn't generate much, either, I don't imagine this could do what the article claims.

Without data, it looks like just a marketing gimmick.

Mar 5, 2015 @ 2:44 PM

Goodyear concept tires shape-shift, create electricity
This pair of concept tires seems more Futurama than future product.
By Eric Tingwall

There was a time when concept cars exhibited such radical pie-in-the-sky thinking that you wondered whether the designers used LSD or had their six-year-olds draw the first sketches. With automakers now rigidly focused on making money, it seems the tire manufacturers are the primary generators of mind-melting creativity these days.

That's certainly the case at the 2015 Geneva auto show, where Goodyear introduced its electricity-producing BHO3 and shape-shifting Triple Tube concept tires. Naturally, they're wrapped in tread patterns that would look crazy even on the bottom of a running shoe.

The BHO3 (above) uses thermoelectric and piezoelectric materials embedded in the tread to convert the energy from heat and deformation into electricity as the tire rolls down the road. Goodyear gives no indication as to exactly how much electricity the BHO3 could generate, but it does make the rather bold claim that "this visionary tire technology could eliminate the vehicle-range anxiety motorists may have with electric cars."

Of course, neither Goodyear nor common sense suggest such a tire will be in production any time soon. We are, however, expecting electricity-producing shock absorbers to become a reality within a few years.

While the name BHO3 has us scratching our heads, the Triple Tube (above) leaves nothing to the imagination. Three tubes located just below the tread allow fine adjustments in the pressure along the inner and outer shoulders and the center of the tire. An internal pump transfers air between the main chamber and the three tubes to vary the tire's contact patch on the fly.

Goodyear imagines three different modes that adapt to the driving conditions. The eco/safety position uses maximum pressure in all three tubes for reduced rolling resistance. Setting the center tube to a higher pressure than the shoulders resists hydroplaning in wet conditions. The sporty mode increases the size of the contact patch by reducing the pressure of the inboard tube.

Pay no attention to the Lexus and Toyota emblems on the wheels. Those are likely the result of a marketing deal and nothing more. Even if the basic science behind the BHO3 and Triple Tube is sound, the practical aspects—durability, weight, cost, and wiring a spinning tire to the body of the car—make these two tires more Futurama than future product.
From: Car and Driver

Hearst Corporation

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©2015 Hearst Communications, Inc. All Rights Reserved.

 

[Punx0r]

The heat from tyre flex should be recoverable (it's waste heat), but not from the deformation itself - there's no net energy input there that I can see. Only the heating of the rubber as a by-product of flexing it back and forth.

I agree that it's marginal at best and the claims are ridiculous.

 

[speedmd]

Tires dissipate a tremendous amount of heat. Interesting calculations on how much can be recovered without drastically cooling them too much or changing the flex much in a negative manner. Not a new concept, but in the light of EV progression, certainly worth exploring a bit for viability. Most likely, costs more than its worth and much less efficient than just pumping up the tires hard. Shocks have some potential also.

 

[mikebikerad]

It is an interesting idea but I am not sure the pizo system could even recoup the energy lost to adding the weight of the system.....especially rotating weight. No way it can generate what the article states I agree that is a BIG stretch.

 

[r3volved]

At least it's a big stretch in the right direction

 

[mikebikerad]

Agreed, but this is about as technically feasible and efficient as adding a little wind generator on the roof Would be better to save the weight of the heat energy recovery system and apply it to a larger pack no?

 

[r3volved]

I could see something like this having a big impact on formula-e where you'll actually see an abundance of heat and pressure changes. I don't know that it would really have much impact (AT THIS INCREMENT) on our current gen EV's.
Again though...it is a step in the right direction. There are a shit ton of losses happening through heat, sound and pressures that don't necessarily 'have to be' all lost.

 

[Punx0r]

There might be a lot of heat energy put into the tyre by flexing, but it's very low grade (only little above ambient), which would make it hard to recover IMO.

The flexing thing definitely doesn't make sense: Any "recovered" energy must be at the cost of making the tyre harder to flex, which will increase rolling resistance.

 

[Drunkskunk]

This heating is caused by rolling resistance. It's energy being wasted by the motor to turn the tire against the resistance of the ground. That's easy enough to calculate, if you know all the variables. But Roughly 1-2% of the vehicles weight is needed to overcome rolling resistance in thrust. it's not a great deal of power but it's significantly more than we worry about on an ebike. this is a long read, but it explains in more detail: http://mb-soft.com/public2/car.html
At a rough calculation, the Vette they use as an example is using a little less than 7hp to over come tire resistance at 60mph, and that power leaves the vehicle in the form of heat at the tires. That's roughly 1/4 of the power it takes to propel the Vette forward. So recovering half of it would be a significant increase in efficiency.

But I seriously doubt they could recover even 1/2 the lost power without effecting the ride quality and handling. And if you don't care about the tire's performance, you don't need a tire so soft and compliant. And that means you can run a harder tire that would be more efficient.

 

[lbz5mc12]

Why not just make spinner rims that generate a charge?

 

[amberwolf]

What would that do? Waste more power by spinning up the rims using power that would have otherwise gone into forward motion, and then get less power than you put into it back out by stopping the spin by loading the generator?

Would be a waste of weight, time, resources, etc.

Might as well put a windmill in the front grille.

 

[lbz5mc12]

Not if you weight the rims to roll forward when the car stops and counter weight them to keep them from rolling backward when the car accelerates.

 

[Lurkin]

windmill in the front grille

At high speed air brakes do have a form of logic.... lol