4 ms·

> Cars rolling over the road apply a tremendous amount of physical energy to the surface. Capture that energy. This is a misunderstanding of thermodynamics. T

• smileysteve 11y ago
  > There is no energy to be captured without adding friction to the existing situation. The point is that there is already added friction (we want cars to grip roads and feet to have cushioned impact) and wear (asphalt is a liquid). Cars already compress roadways, brake on them, etc. To the other extent, a flexible base could reduce some of the wear by adding flexibility. For "Smart Steps" yes, they consumer energy from the walker, but the walker also has less impact on joints. Running tracks prefer absorbing surfaces (rubber) for the increased friction vs concrete - not absorbing energy.
  • mangeletti 11y ago
    Your point is true, if we were to replace all the asphalt roads with a new form of road. I suspect the energy and material requirements for making an energy-capturing dampening system that feels similar to asphalt to the vehicles overhead would far outweigh the benefits (I'm picturing some sort of electrolyte putty with thousands of wire leads every meter, funneling microamps of energy into a the heavier wire in a conduit underneath).
    • beat 11y ago
      Yeah, whether it can be done cost-effectively is a different question.
• beat 11y ago
  Of course it adds friction, but that friction could be pretty negligible. You don't need to capture all the energy introduced by a heavy vehicle passing over the surface. Just capture a little of it.
  • JoeAltmaier 11y ago
    That's just dumb, I'm sorry. There are losses in any process. Any power generated by this Rube Goldberg idea, would cost far more in lost power to the car. There is no free lunch.
    • beat 11y ago
      Roads already flex and compress in response to the moving weight of vehicles traveling on them. That's basic materials engineering. Where does that energy currently go? Thermal loss. Can we convert some of that thermal loss into captured electricity? Vehicles are already losing friction energy to roads. This doesn't need to add to it.
      • JoeAltmaier 11y ago
        Power plants like to generate superheated steam to drive turbines. And now we suppose a tenth of a degree of warming in the pavement is worth going after? Go back to engineering school for a few more years, is my advice to anybody trying to get energy out of roads. That potato clock we made in 2nd grade generates more energy.
  • mapt 11y ago
    Some technical ideas are stupid in a trolly way: it's difficult to actually put numbers to the reason this is bad, because you have not actually put forth a proposal, only an idea, and we would require a detailed physical simulation of your proposal to be able to demonstrate with proof "This is a fucking stupid idea". Nevertheless, design enough things and mess around with energy capture schemes enough and you do develop some intuition in the matter of how hard it would be to implement, how much you would actually get back, how negligible that is. That intuition is screaming at us that this is a waste of time, your idea is bad, and you should feel bad. What is easy to point out that you're trying to shift the burden for electrical power generation from solar/nuclear/coal, on to scarce and expensive oil, mediated through low efficiency automotive engines, and in the process increase road construction costs by orders of magnitude. The only free lunch you get in automotive regenerative power for every car that passes, is on the downslope of very long hills at high speed. You can regenerate power here through the wheels (and that's slowly being put into the fleet as we start to use wheelhub motors & large battery banks), or through in-road baffles. You could do the same thing at traffic lights, but they don't have a predictable deceleration curve and speeds are much lower (making it feel choppy) and it's not an environment where you want to mess with people's sense of acceleration, for safety reasons.