Audi is working on a suspension that gets power from bumpy roads

[Daox]

Its not the first time we've heard of this, but its the first time I've heard of an OEM looking into it. The other times I've heard of it, it was universities doing research on it. Very cool stuff IMO.

Audi is working on a suspension that gets power from bumpy roads

In testing, eROT recovered an average of 100 to 150 watts on a typical German road, three watts from a fresh piece of pavement, and 613 watts on a rough stretch of tarmac...

...

In the US, the Q7's supercharged 3.0-liter V6 returns a combined rating of 21 miles per gallon, which works out to 11.2 liters per 100 kilometers. Apply eROT's 0.7L/100km savings, and the Q7's economy would improve to 10.5L/100km, or 22.4 mpg, a 1.4-mpg improvement. That's not huge, but because math, 0.7L/100km is more dramatic on a more fuel efficient vehicle – taking an A3's 27-mpg combined rating and adding eROT would drive efficiency up 2.4 mpg, for example.

[Stubby79]

Took 'em long enough...

There probably a lot more ways to make electricity from waste energies.

[jjackstone]

I've thought about these things for a long time since I came up with a similar idea when I was a EE student about 30 years ago. The tests show how much energy is being recovered and I assume that means into the battery. I don't see anywhere that the testing includes the effect of what would almost certainly be a substantially heavier system than standard shock absorber system. Or maybe I'm wrong. Maybe Audi has been able to make a light weight generator/charger/battery system.

The part about additional mpg improvement in an already more efficient vehicle is probably wrong since the more efficient vehicle is likely that way due to aerodynamic properties which would over ride the linear function that the articles author is attempting to use. Just my thoughts.

I really would like to see this work, but I'm not sure the added complexity(and cost) makes it worthwhile.
JJ

[Fat Charlie]

We're out of gas. I've got a great idea...

[California98Civic]

So they eliminate the alternator, or just use it very little? Is the supercharger electric? Heat recover would be cool too... those tiles that produce energy from heat. Combine heat recovery, solar panels, regen braking, suspension, and you could have some really goo- looking, low-profile, and substantial electricity production is a single car, no?

[freebeard]

Here's an entire drivetrain that's not much more complex:

http://www.zf.com/corporate/en_de/products/product_range/cars/cars_electric_twistbeam.shtml

They're recovering <1hp. The gearbox and alternator could be replaced with piezoelectric/triboelectric crystals.

[jamesqf]

...but because math, 0.7L/100km is more dramatic on a more fuel efficient vehicle...

Probably not, because the more fuel efficient vehicle is almost certainly proportionately lighter. Less moving mass, less energy to recover.

As for what to do with the recovered energy, such a system is perfect for hybrids or full EVs.

[jakobnev]

Seems great for pulse and glide.

[Fingie]

sometimes my mate toyed with the idea of attaching a normal foot pump to the suspension of his pickup so it could fill a normal air tank for free

[freebeard]

Makes more sense to me. Instead of a foot pump, could you use an air shock? If you figure out the one-way valving?