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Using electro gravity tiles, there is an emerging technology that can generate electricity from moving vehicles. If we continue to populate the highways and roads, we might as well extract energy from their motion. How cool is that? 

But it's not meant to do that. It's meant to save unused energy. Independently of whether it actually works of course.Ivan Seeking said:extremely inefficient means of converting petro energy to electrical energy.
humanino said:But it's not meant to do that. It's meant to save unused energy. Independently of whether it actually works of course.
Ivan Seeking said:Technically, the first tile encountered might.![]()
Ivan Seeking said:This is completely bogus. The energy from the tiles comes from petroleum powering the cars. It would be an extremely inefficient means of converting petro energy to electrical energy.
But no, really, it is the movement of the cars and trucks, which could be powered by... electricity ! At least in principle. Of course it has a very low efficiency, but the idea would be to use what is not at all for now. The numbers are very suspicious though. In particular, the question would be "how much would that cost compared to other means of producing (sustainable, free) electricity".Ivan Seeking said:the source of the energy is petroleum
humanino said:
So, technically, would the number of miles per gallon increase ? (one cubic milliter per light year counts)
We put an accelerometer in a box once, which we were shipping overseas. For insurance purposes. I was amazed by the values which can be reached in a truck, much more than what can be reached in a plane for instance. Those are up-down accelerations. This is completely useless as of today. They are very short excursions, and could not generate much power, I do not believe the numbers in the video. But technically, there is a non-zero effect. Of I may be out of my mind today...Ivan Seeking said:I was saying that we might net a little energy from the road for a millisecond, but only until we had to climb out of the hole from the first dot.
humanino said:We put an accelerometer in a box once, which we were shipping overseas. For insurance purposes. I was amazed by the values which can be reached in a truck, much more than what can be reached in a plane for instance. Those are up-down accelerations. This is completely useless as of today. They are very short excursions, and could not generate much power, I do not believe the numbers in the video. But technically, there is a non-zero effect. Of I may be out of my mind today...![]()
So... you'd power an electric generator with an electric motor powered by an electric generator?humanino said:But no, really, it is the movement of the cars and trucks, which could be powered by... electricity !
It has negative efficiency.At least in principle. Of course it has a very low efficiency.
The only unused energy in a car driving down a road is in the gas tank. Attaching a power generating device to the road therefore requires burning more gas.It's meant to save unused energy.
That isn't what is being claimed in the video, but I agree: the amount of energy dissipated in shocks is extremely small. There is a reason you don't see heat sinks bristling the sides of a shock absorber.Ivan Seeking said:I see what you are saying: I think that is a different situation from inducing vertical accelerations, but we are already wasting energy as heat in shock absorbers.
I wonder if linear generators could be used as shock absorbers in electric cars, and what would be the returns? As you said, probably too small to even consider, but I have never even looked at that one.
Well it is far from being trivially as clear as you seem to suggest !russ_watters said:Attaching a power generating device to the road therefore requires burning more gas.
Take an individual car. Less than 10% accelerates the car, and approximately 1% of the gas is used to move the people in it. There are losses all over the place.russ_watters said:The only unused energy in a car driving down a road is in the gas tank.
The video is so bad, it is tough to even detect coherent thoughts (they mix energy and momentum, for example). But they did make one specific claim: the total energy available in moving cars. A quick google shows the US uses 40 billion gallons of gas a day or 14.6 trillion a year. A gallon of gas contains 36 kWh, so that's 530 billion kWh per year. That's "of the order" of what they claimed the energy available was.humanino said:Well it is far from being trivially as clear as you seem to suggest !
No one said it couldn't generate any power, we just said it can't generate a significant amount of power.Take a fat trucker, you will not tell me that a bump on the road can not generate accelerations of the order of a few g, proof is as simple as him jumping from his seat now and then. Attach some kind of electrical generator to him, and you will definitely get some power out of it. Certainly not enough to light a bulb, but in principle at least it works, and in that case I do not think it affects the amount of gas burnt by the engine, at most it makes the trucker jump less high.
No. What you are suggesting doesn't work the way you are suggesting. The purpose of shock absorbers is to absorb energy caused by bumpy roads. If a road is perfectly smooth, you don't need shock absorbers and no energy is wasted there and your fuel usage goes down. Blanket the roads with a material that is soft enough to deform and generate electricity, and the energy expended by the engine again has to increase to compensate. It would be like driving your car through jello.Therefore, I imagine it possible indeed to use the same kind of generator to the road, possibly not affecting the gas at all, but reducing the stress in the shock absorbers for instance, as Ivan mentioned.
I didn't say "lost" I said "unused'. Energy that has been lost has been used -- just not used for what you are trying to accomplish.humanino said:Take an individual car. Less than 10% accelerates the car, and approximately 1% of the gas is used to move the people in it. There are losses all over the place.
Amory Lovins @ TED
Oh I absolutely agree about (against) the video and their claims, although I was unaware of the numbers (36 kWh is a very useful number to remember !).russ_watters said:A gallon of gas contains 36 kWh, so that's 530 billion kWh per year. That's "of the order" of what they claimed the energy available was.
I see, and again completely agree with your points. I indeed assumed that the material would not be any smoother than an actual road. It is clear for everybody that the output would certainly be negligible, but most importantly, in any case (whatever the power available) it would probably be best to use "clever" shock absorbers as Ivan suggested.If a road is perfectly smooth, you don't need shock absorbers and no energy is wasted there and your fuel usage goes down. Blanket the roads with a material that is soft enough to deform and generate electricity, and the energy expended by the engine again has to increase to compensate. It would be like driving your car through jello.
Interesting clip (I may have to read the book), but it is clear that he wildly overstates the potential improvements and understates the cost. One clear one is that he says the first 20% energy efficiency improvement in airplanes is free. The reason for the statement is that it is already incorporated into new airplanes. But wait: you have to buy a new airplane to realize the gain! Not only that, but is the new airplane the same cost as the old one? No: you pay extra for the technological improvements of the new planes.humanino said:
Gokul43201 said:This thread belongs in the Debunking Product Claims forum. What a joke that video is!
Ouabache said:This was presented in an NBC news item. There is a videoclip titled "Energy harnessed from passing cars" that may be found by browsing msnbc news videoclips under "technology and science". Alternatively you can view this clip is by following this link. As this is just a news item, I recommend this post moved back to 'general discussion'.