Yeah, so they've figured out a way to steal energy from other people and convert it to electricity. On top of that such a small amount of fuel energy is converted to motion in the first place that this has to be one of the most efficient methods of generating electricity. It might be useful in cases where the vehicles benefit in some way from the produced energy (as in the cited example to help slow down trucks) but otherwise the vehicle owners should bill the company that owns the energy stealing device.

Lower my fuel economy AND perform a lossy chemical combustion to mechanical to mechanical to induction generator conversion? Sign me UP!

Or you could use the plates to enforce the speed limit

@ludwigk: what else are you gonna do what that braking energy?

Not to be super-picky, but it's actually the gravitational potential energy of the truck that's being used, not its kinetic energy.

@ludwigk: It's a great idea though if done as already noted by NOT lowering your fuel economy. If they placed this on, say, every interstate off-ramp. Everyone needs to slow down anyways. Lots of traffic. It's not going to hurt your fuel efficiency if you're already trying to stop. all it will do is save you some wear and tear on your brakes. Granted, it's probably not generating as much power as that article initially claims, but still...every bit counts.

Hold on, so in the future our electric cars will run electric generators to give us less electricity back than we originally contributed?

awesome.

the trucking companies should flip the bill in the first place! then the drunk drivers!

@SgtMac02: ah, awesome point.

If the companies take care of the part of the road this is installed, I don't see the problem. With the enormous amount of unkept roads, bad drivers (which account for most of my 'slow downs'), traffic jams and other hazards having this in the road wouldn't phase me in the slightest. I think it's brilliant.

Oh my god I had this idea years ago! The downhill part would be more of a benefit to the provider of energy. Maybe also add some wind turbines to the side of the road to capture all the side moving wind force these trucks generate as well.

@bobmarley101: Not that I'm claiming I know anything about physics.. but isn't it the case that potential energy is "stored" energy and when it is used it becomes kinetic? Thus the electrical generation is from kinetic energy? I dunno....

I always wondered why they didn't apply this model to human traffic... like in a subway station or something.

"this would be even better for the times when you actually do want to slow down, like going down a hill, where they could load up on these plates and slow down cars"

@GiltProto: There are a lot of places where it can actually be a benefit like downhills as mentioned above or freeway exit ramps.

@Geeum: I was actually jsut reading the TreeHugger articles that this post came from. Someone there mentioned the same idea about the wind turbines. Unfortunately (as another astute reader had pointed out better than I can explain) using the turbines would actually disrupt the airflow in such a way as to cause more of a hindrance to the vehicles. This really WOULD be stealing energy from them rather than harnessing energy that would have otherwise been wasted.

@bobmarley101: You can't make energy from nothing. Although you're correct that it is gravity pulling down, it is the combustion engine that is powering the vehicle. So the source of the energy must be the combustion engine not gravity (which is really redirecting the kinetic energy downward). The road gives way a little bit to make the electricity, you could even think of it as driving through sand though this is an exaggerated point. Hence more friction while driving.

That's a good point about putting them places where trucks would need to break anyway like off ramps or going down a mountain.

I am calling up Visa and asking them to allow me to take one one-hundreth of a penny from each transaction. No one will notice the money going away because it is so small, and in less than a few minutes I will be a millionaire. Genius!

(Someone please smack the nimrod that came up with the concept of stealing energy from vehicles powered by fossil fuels to generate electricity.)

@Maksimir: Now THAT's an idea that I do like! Using the normal human foot traffic and harnessing that energy. Especially here in the US where we have a population of people who generally need a little more exercise anyways. You could put it in Subway Stations, shopping Malls, crosswalks in busy cities, the entrance to your favorite strip club...anywhere that gets lots of foot traffic...

@bobmarley101: Uhh. No. You can't pass potential energy from one object to another without inducing kinetic energy. As the truck passes over the plates, the potential change produces kinetic energy. The plates themselves drives the generators.

@Discofunk: The energy is harnessed by the trucks "falling" onto the plates, since the plates depress under heavy weight, so you could say they are almost given potential energy which is then turned into kinetic energy. I think that both are manipulated, you could argue either way

Cool idea. Just so long as its only installed in places you want to slow down anyways. I wonder what the cost to install and maintenance is like vs power generated though?

@Monty: Duh! It's called "interest" and card companies already keep it all for themselves.

Put one of these in front of every McDonalds, DQ, and other fast-food franchise and generate AC off of the passing tonnage.

(Come on, you BioDiesel folks would have nothing if there weren't over-weight folks)

im for it.

@Elcheecho: @SgtMac02: Right, you're both assuming that its being implemented this way, but that isn't what the article says!

Taken from the article:

"Fast-forward eight years, and here's Kenney, dressed in a crisply ironed shirt and slacks, standing in the compound of the largest terminal operator at the 255-acre Port of Oakland. A long line of trucks snakes its way to the San Francisco Bay, where two cargo ships wait to be loaded. One truck rumbles at about 15 miles per hour over a group of narrow plates embedded in the asphalt, and a moment later, a solar-powered shed beside the road begins to groan and rattle ominously."

Sounds like they are implemented more like speed bumps than a break assist.

My point was that the generation part of the system doesn't actually steal any kinetic energy from the trucks. When the truck drives onto the plate, the plate sinks (actually slightly increasing the kinetic energy of the truck by adding a down component to it). But the energy taken to push the plate down isn't taken from the truck's kinetic energy, it's taken from it's potential energy. The problem is that if the road is completely level the truck then has to go up a tiny bit on the other side of the plate, which slows the truck down a little. But that's incidental, and not a part of the power-generation system.

@Monty: I believe they already tried that at Initech with some unfortunate end results...

+ Watch video

@ludwigk: I made no assumptions of it's implementation. I said "It's a great idea though if done as already noted by NOT lowering your fuel economy. If they placed this on, say, every interstate off-ramp."
I was referring to the last paragraph of Jason's post that had already made this point clear.

The Federal Government is using them at Points of Entry (at least in the South West)where you have to slow down anyway. Combined with solar, they are looking to put Border Station facilities "off the grid."

But more to the point, there will never be a magic bullet that solves the energy crisis. Things like the Dragon Power Station combined with solar combined with wind combined with increased efficiency in electronics combined with conservation will go a long way toward solving the problem.

@bobmarley101: In other words, what @ab12 said.

Also, again being picky but this time to myself, that was supposed to be "its potential energy."

The energy theft version could be a good way for busy roads to make money without toll booths. I'd be willing to bet that this model is a lot more fuel efficient than waiting in line to pay your toll.

Sounds like a perpetual motion machine to me. The guy is a cook!

Seriously, why is it that you cover this concept in a positive light, but when someone tries to harness power from say gravity, magnets or the earth's rotation they are called crazy?

I would like to install these on the highway near my house to serve as a "noise tax." Assuming of course that vehicles passing over the plates doesn't induce even more noise.

Put this on:

Offramps
Steep hills on the 'down' traffic side
In front of stop-signs
In front of stop-lights (if it can be turned off for green lights)
In every parking space (only works if it takes energy to enter but not to leave)

Put this anywhere else and I will buy property under some high tension lines and start "recycling" the electromagnetic fields created by the juice in the lines to offset the mpg I am losing.

Of course once we all drive electric cars, the energy can be more efficiently captured by our vehicles' brakes.

@bobmarley101:
Actually isn't that the exact power generation system? As each wheel comes up again after pushing down t plate (which moved the hydraulic fluids which turned the generator) kinetic energy in the vehicle is now converted back to potential energy which naturally slows the vehicle.

I think the whole slowing down thing for braking that everyone keeps talking about is a minimal property of the device. First of all you'd need lots and lots of such devices along a downhill ramp to actually slow anything down significantly. Indeed the whole point of the gizmo is to only extract a small amount of energy from a moving vehicle. There are far better ways to generate electricity by braking a vehicle.

I think where this technology might be a benefit is where the electricity could be harnessed to power remote stoplights or facilities where it doesn't make sense to bring in long distance power lines because of the cost. But to power thousands of homes, well that's just lunacy.

You can't get something from nothing, so it steals energy from trucks. This should be illegal, just like stealing an induced current from power lines is illegal.

@bobmarley101: The problem is that if the road is completely level the truck then has to go up a tiny bit on the other side of the plate, which slows the truck down a little. But that's incidental, and not a part of the power-generation system.

It isn't incidental - the amount of energy recovered from a truck falling 1cm will always be less than the amount of energy required to lift that truck 1cm. The 2nd law is a pain that way. Unless the vehicle is trying to slow down anyway, it is stealing from that vehicle.

@Maksimir: And the great part about that is that it would actually cause the foot traffic to work a little harder, thus maybe helping the ongoing obesity problem, at least in the U.S.

I saw this like two years ago (and in England I believe) on the science channel's "Beyond Tomorrow" (formerly Discovery's "Beyond 2000")

@zenpoet: We could just cut to the chase and make a battery implant that sucks the fat out of you and converts it into electricity.

It cuts down on noise also!

@badweasel: Because those are blatant lies, never publicized truthfully, and produce significantly less power than is functionally usable. Being able to power homes, though, is a significant ability.

Since trucks have to drive anyway, why not harness just a little bit of that power back? If you all seriously think this is gonna hurt driving that much, I pity your brains. They must be lonely.

@Cis