[cmeisenzahl]

Lots of untapped potential sources out there still, I'm sure.

http://news.bbc.co.uk/2/hi/uk_news/e...et/4535408.stm

"A road ramp that uses passing cars to generate power has been developed.

Dorset inventor Peter Hughes' Electro-Kinetic Road Ramp creates around 10kW of power each time a car drives over its metal plates.

More than 200 local authorities had expressed an interest in ordering the £25,000 ramps to power their traffic lights and road signs, Mr Hughes said.

Around 300 jobs are due to be created in Somerset for a production run of 2,000 ramps next year.

Plates in the ramp move up and down as vehicles pass over them, driving a generator.

"The ramp is silent, comfortable and safe for vehicles," Mr Hughes said.

Underneath the Electro-Kinetic Road Ramp
Inventor Peter Hughes spent £1m developing the ramps

Depending on the weight of the vehicle passing overhead, between five and 50kW can be generated.

The prototype was created and tested at Hughes Research unit at the Westland Helicopter base in Somerset, at a cost of £1m.

The concept has been developed by Dorset-based Mr Hughes over the past 12 years. He recently approached councils across the country with the final patented project."

[Doofy]

I dunno. I'm not too comfortable with "kerbing" over one of those things. No matter how safe they say it is for vehicles, driving over that (vertical face) has got to take out some punishment somewhere.

[Gamoe]

Very interesting! However, I too think that the cumulative effects on automobiles should be studied before this becomes widespread. Then again, I think bumpers (the ones on the pavement) are not that great for cars either, and they're in lots of places.

[cmeisenzahl]

I wondered a bit about that myself. It almost looks backwards in the pic from what I expected. I don't understand why the steep face would be necessary.

[Mastrap]

I think it should be ok - as the ramp moves down there should be very little impact.
Now, my question: Does this actually save energy, or is the energy created paid for by a miniscule increase in gas consumption, as the cars driving the ramp down need to create more power than they otherwise would?

I was always crap at physics, anybody care to enlighten me?

[macintologist]

What about those machines that use wind created by passing cars to generate energy?

[The Godfather]

Originally Posted by Mastrap

I think it should be ok - as the ramp moves down there should be very little impact.
Now, my question: Does this actually save energy, or is the energy created paid for by a miniscule increase in gas consumption, as the cars driving the ramp down need to create more power than they otherwise would?

I was always crap at physics, anybody care to enlighten me?

Those are some valid concerns. These generators will produce much less energy than the energy wasted at slowing down the car before the bump, and then picking up speed after the bump.
It would be sensible to install them at very remote locations where electric power is not available, but needed to run a small appliance, where vehicles slow down anyway: pay tolls and railroad crossings.
Even with the bad efficiency of this system, it would be more economical than laying out tens of miles of wire for these things.
I hope this technology, for the sake of the inventor, finds a niche market that's not already better served with solar energy.

[tooki]

And what'll it do to bicycle traffic?!?

tooki

[Doofy]

Originally Posted by tooki

And what'll it do to bicycle traffic?!?

I was wondering what it'd do for bikes (powered variety) on icy roads. I really don't think they've thought this one through (which means Her Majesty's government will probably install them everywhere).

[Spliffdaddy]

Physics dictates that this 'free' energy would be siphoned from the cars - resulting in a speed decrease - which would need to be overcome by stepping on the cars' accelerator pedal.

In reality, this is a very inefficient method for producing power.

[Doofy]

Originally Posted by Spliffdaddy

Physics dictates that this 'free' energy would be siphoned from the cars - resulting in a speed decrease - which would need to be overcome by stepping on the cars' accelerator pedal.

In reality, this is a very inefficient method for producing power.

But since we've already got millions of speed bumps siphoning the energy out of our cars, replacing those bumps with these things wouldn't lose any more energy.
(but then these things would probably be in addition to the existing speed bumps, not instead of. Our authorities aren't the sharpest tools in the shed)

[tooki]

And also, they say 10KW each time a car runs over it? That's enough to run three electric ovens. I don't think a car engine produces that much heat, never mind that much motion. That number sounds wildly exaggerated to me, at least without knowing a lot more about it.

tooki

[Azzgunther]

a.) No energy loss if these things are installed on offramps, where the vehicle is slowing down anyway.

b.) Doofy - look closer at the picture; it is not actually a flat-face that the car drives into, but rather a gradual rise. I thought the same thing you did. It's just a bad picture.

[itistoday]

Originally Posted by tooki

And also, they say 10KW each time a car runs over it? That's enough to run three electric ovens. I don't think a car engine produces that much heat, never mind that much motion. That number sounds wildly exaggerated to me, at least without knowing a lot more about it.

tooki

More like: without knowing about it, you have no grounds to question it.

[villalobos]

Originally Posted by Spliffdaddy

Physics dictates that this 'free' energy would be siphoned from the cars - resulting in a speed decrease - which would need to be overcome by stepping on the cars' accelerator pedal.

In reality, this is a very inefficient method for producing power.

Maybe, maybe not. The 'free' energy will come from gravity. And none of us paying for it. There will some loos through friction others. It might still be a positive energy output a the end. Gravity is definitely the most abundant 'free' energy around us.

[Spliffdaddy]

Originally Posted by Azzgunther

a.) No energy loss if these things are installed on offramps, where the vehicle is slowing down anyway.

Ahh, but all those hybrid cars use the energy from the car slowing slowing down to recharge the batteries. So, in effect, you're taking energy from those batteries, Stealing it, if you will.

[Doofy]

Right, here you go.

http://www.hughesresearch.co.uk/Pict...uide_Thumb.jpg
(warning: very slow loading 1.5 Mb image).

I'm guessing the first tractor cab to roll over it will mess it up (rear axles too close together to allow the mechanism to do its work).

[Doofy]

Originally Posted by Azzgunther

b.) Doofy - look closer at the picture; it is not actually a flat-face that the car drives into, but rather a gradual rise. I thought the same thing you did. It's just a bad picture.

I've just been and looked (see above post). Yep, it's a bad picture on the BBC site, for sure.

[sknapp351]

Originally Posted by itistoday

More like: without knowing about it, you have no grounds to question it.

It would seem to me that not knowing about it is the perfect reason to question it.
SAm

[itistoday]

Originally Posted by villalobos

Maybe, maybe not. The 'free' energy will come from gravity. And none of us paying for it. There will some loos through friction others. It might still be a positive energy output a the end. Gravity is definitely the most abundant 'free' energy around us.

bingo

[itistoday]

Originally Posted by sknapp351

It would seem to me that not knowing about it is the perfect reason to question it.
SAm

Semantics. We're using "question" two different ways. You're using it as in: "to learn more; find out about". I'm using it as: "Disregarding as bullsh1t, saying it's not so".

[macsfromnowon]

Originally Posted by Spliffdaddy

Physics dictates that this 'free' energy would be siphoned from the cars - resulting in a speed decrease - which would need to be overcome by stepping on the cars' accelerator pedal.

In reality, this is a very inefficient method for producing power.

I think Spliffdaddy is on the right track: There is no "Free Energy" - it has to have a dragging effect on cars passing over it. Only where you KNOW cars need to be slowing down is it really being useful - sort of using the same principle as a hybrid: brake by doing more than creating friction at the brake pads, but doing something useful with it.

I really wonder whether it isn't a somewhat Rube Goldberg approach. (esp. compared to hybrid efficiency)

[macsfromnowon]

Originally Posted by Doofy

Right, here you go.

http://www.hughesresearch.co.uk/Pict...uide_Thumb.jpg
(warning: very slow loading 1.5 Mb image).

And why did they think this cartoon needed the resolution of a 1.5Mb image?

[itistoday]

Originally Posted by macsfromnowon

I think Spliffdaddy is on the right track: There is no "Free Energy" - it has to have a dragging effect on cars passing over it. Only where you KNOW cars need to be slowing down is it really being useful - sort of using the same principle as a hybrid: brake by doing more than creating friction at the brake pads, but doing something useful with it.

I really wonder whether it isn't a somewhat Rube Goldberg approach. (esp. compared to hybrid efficiency)

I don't think so. The energy does not come entirely from the car.

There are several energies at work here:

1) The chemical energy from the car's engine
2) The kinetic and potential energies of the speeding car itself
3) The gravitational potential energy of the car
4) The potential energy of the spring under the ramp

As the car passes over the ramp the car's chemical energy is used to move the car up the ramp about half a foot. However, in reality little energy comes from the car's engine. Here is why:

The car has a momentum as it approaches the ramp, as it goes up the ramp its speed slows down and its kinetic energy is converted to its potential energy, however, on its way down, this energy is almost entirely converted back to kinetic energy as the car speeds up down the ramp. But, that's what would happen with a fixed ramp. The situation here is a bit more complicated however. As the car goes up the ramp the ramp actually lowers, meaning the car does not go up as high as it would have to have gone on a fixed ramp. Gravity is doing a lot of the work here. The car's gravitational potential energy increases a bit as it goes up the ramp but at the same time the ramp goes down slowly, turning the rod that turns the generator. At the same time, you have the spring's potential energy resisting the downward motion of the ramp. It is important because it's what allows this system to repeat (because it raises the ramp for the next car).

Anyways, the point is that not 100% of the energy derived to power the generator comes from the car's engine itself. Part of it comes from the spring's potential energy and a greater part comes simply from gravity.

It would be a fun physics problem to calculate exactly what the percentages are... Any takers?

[f1000]

The energy generated by these oscillating ramps MUST come from the burning of gasoline/diesel. In that sense, the ramps don't harness free energy.

This is not to say that the ramps couldn't maximize the useful work captured from the burning of a gallon of gasoline. Ramps could be strategically placed to capture energy that would've been lost through non-regenerative braking.

Still, I fail to see how these devices are more practical than solar cells. For one thing, if the ramps go up and down, they won't be of any use as speed bumps.

[f1000]

Originally Posted by itistoday

I don't think so. The energy does not come entirely from the car.

There are several energies at work here:

1) The chemical energy from the car's engine
2) The kinetic and potential energies of the speeding car itself
3) The gravitational potential energy of the car
4) The potential energy of the spring under the ramp/

1, 2, and 3 ALL come from the burning of gasoline. As for 4, an uncompressed spring contains no potential energy. In fact, compression of the spring would REQUIRE an input of energy.

[itistoday]

[whoops]

[itistoday]

Originally Posted by f1000

1, 2, and 3 ALL come from the burning of gasoline. As for 4, an uncompressed spring contains no potential energy. In fact, compression of the spring would REQUIRE an input of energy.

1 -- no sh1t it comes from the engine
2 -- true, it comes from the engine, but the point is that if you were to turn the engine off as the car were traveling it would still keep on moving.
3 -- No, wtf, this does not come from the "burning of gasoline".

You are correct that an uncompressed spring has no potential energy, however, you don't seem to understand that the input energy comes almost entirely from gravity, and only very little from the gasoline.

[f1000]

Originally Posted by tooki

And also, they say 10KW each time a car runs over it? That's enough to run three electric ovens. I don't think a car engine produces that much heat, never mind that much motion. That number sounds wildly exaggerated to me, at least without knowing a lot more about it.

You're confusing power (kilowatts) with energy (kilowatt-hours).

[f1000]

Originally Posted by itistoday

1 -- no sh1t it comes from the engine
2 -- true, it comes from the engine, but the point is that if you were to turn the engine off as the car were traveling it would still keep on moving.
3 -- No, wtf, this does not come from the "burning of gasoline".

You are correct that an uncompressed spring has no potential energy, however, you don't seem to understand that the input energy comes almost entirely from gravity, and only very little from the gasoline.

^ OK, kid, whatever.

[Spliffdaddy]

gravity is a really crappy source of energy.

It takes energy to defeat the pull of gravity in order to harness any of gravity's energy.

While gravity does, indeed, compress a spring - something had to relax the spring to begin with...and that something was probably the car's engine (or a jack or hydraulic lift).

The only good source of gravity energy is falling rain, rivers, and landslides. All of which rely on natural forces like the sun's heat (lifting moisture) or techtonic plate shifting (in order to get the land up high enough to fall.

[itistoday]

Originally Posted by Spliffdaddy

While gravity does, indeed, compress a spring - something had to relax the spring to begin with...and that something was probably the car's engine (or a jack or hydraulic lift).

What "relaxes" the spring is the spring itself. There are two kinds of springs, those you stretch and when you let go they shrink back down, and those you squeeze, and when you let go they stretch back to their normal size. The one used in this scenario is the latter, and it's simply the chemical properties of the material it's made out of that allow it to return to its normal shape. It's the same kind of spring used in cars to absorb shock.

[itistoday]

Originally Posted by f1000

^ OK, kid, whatever.

Sure thing, gramps.

[ghporter]

This sounds like a new turn on the idea of using tides to generate electricity. However, here, you apparently have the weight of the car providing the energy input, rather than incoming or outgoing tides. Depending on th stiffness and strength of the springs involved, it could actually be practical.

[11011001]

Originally Posted by itistoday

1 -- no sh1t it comes from the engine
2 -- true, it comes from the engine, but the point is that if you were to turn the engine off as the car were traveling it would still keep on moving.
3 -- No, wtf, this does not come from the "burning of gasoline".

You are correct that an uncompressed spring has no potential energy, however, you don't seem to understand that the input energy comes almost entirely from gravity, and only very little from the gasoline.

Yes, the direct source of energy is gravitational potential energy (and some kinetic energy, as the cars momentum and inertia bears down on the ramp at a very insignificant angle). But where did that energy come from? The gravitational potential energy actually came from kinetic energy as the car traveled up the ramp, the kinetic energy was produced by the engine converting chemical potential (the gasoline) energy to kinetic energy. In the end, the energy put into the entire system comes from the gas, and is converted between various forms. So, I think f100 is correct.

edit: Why am I confused? This is basically what you said in your previous post. nevermind

[itistoday]

Ok, here's an easy proof that gravity does a lot of the work in this case and not the engine:

Imagine a rocket car flying along a road in a space that has no gravity. There's a ramp up ahead identical to the one described in the article. When the rocket car hits the ramp the car gets deflected upward because the thing the ramp is connected to is stationary. The ramp decompresses a little and in this situation a little energy is derived from the car, and all of the energy comes from the car's engine.

As you can see, this is clearly not the case, and gravity does a lot of the work on the ramp.

[tooki]

Originally Posted by f1000

You're confusing power (kilowatts) with energy (kilowatt-hours).

You win the cookie!

No, I am not confusing them... I deliberately quoted the number they gave. I'd hoped someone else would pick up the mumbo-jumbo numbers! The whole point of my post was to point out the preposterousness of the numbers given in the article.

tooki

[Mr Kino]

here is that 1.5meg image a little smaller.

[itistoday]

Originally Posted by 11011001

Yes, the direct source of energy is gravitational potential energy (and some kinetic energy, as the cars momentum and inertia bears down on the ramp at a very insignificant angle). But where did that energy come from? The gravitational potential energy actually came from kinetic energy as the car traveled up the ramp, the kinetic energy was produced by the engine converting chemical potential (the gasoline) energy to kinetic energy. In the end, the energy put into the entire system comes from the gas, and is converted between various forms.

I do see what you're saying, but I'm pretty sure that that's not the case. The car always had gravitational potential energy stored in it, and gravity does work on the car to push it down on the ramp as it goes down. The car's engine is not the thing that's pushing it down on the ramp. Read my above example of a rocket car in zero g.

[Fyre4ce]

Originally Posted by villalobos

Maybe, maybe not. The 'free' energy will come from gravity. And none of us paying for it. There will some loos through friction others. It might still be a positive energy output a the end. Gravity is definitely the most abundant 'free' energy around us.

This is inaccurate. Gravity is not free energy. It takes energy to raise something against gravity, and that energy is released when the object falls, but if the car ends up at presumably the same height as it would otherwise, there is no gain. Hypothetically, if you decreased the height of the road surface after the bump by, say, four inches, then it would work, but you would have to decrease the height of EVERY road connected to the bump by four inches, which is impossible because the road loops back on itself.

There is no such thing as free energy.

[Fyre4ce]

Originally Posted by itistoday

I don't think so. The energy does not come entirely from the car.

There are several energies at work here:

1) The chemical energy from the car's engine
2) The kinetic and potential energies of the speeding car itself
3) The gravitational potential energy of the car
4) The potential energy of the spring under the ramp

As the car passes over the ramp the car's chemical energy is used to move the car up the ramp about half a foot. However, in reality little energy comes from the car's engine. Here is why:

The car has a momentum as it approaches the ramp, as it goes up the ramp its speed slows down and its kinetic energy is converted to its potential energy, however, on its way down, this energy is almost entirely converted back to kinetic energy as the car speeds up down the ramp. But, that's what would happen with a fixed ramp. The situation here is a bit more complicated however. As the car goes up the ramp the ramp actually lowers, meaning the car does not go up as high as it would have to have gone on a fixed ramp. Gravity is doing a lot of the work here. The car's gravitational potential energy increases a bit as it goes up the ramp but at the same time the ramp goes down slowly, turning the rod that turns the generator. At the same time, you have the spring's potential energy resisting the downward motion of the ramp. It is important because it's what allows this system to repeat (because it raises the ramp for the next car).

Anyways, the point is that not 100% of the energy derived to power the generator comes from the car's engine itself. Part of it comes from the spring's potential energy and a greater part comes simply from gravity.

It would be a fun physics problem to calculate exactly what the percentages are... Any takers?

100% from the car's engine
0% from the spring
0% from gravity

[Fyre4ce]

Originally Posted by tooki

You win the cookie!

No, I am not confusing them... I deliberately quoted the number they gave. I'd hoped someone else would pick up the mumbo-jumbo numbers! The whole point of my post was to point out the preposterousness of the numbers given in the article.

tooki

Actually, tooki, I believe their numbers, but they are very deceptive. If a car generates 10 kW when it passes over the ramp, it's only generating that power while the car is on top of the device! Kilowatts is a rate of energy (known as "power"), and while the rate may be high, the total energy delivered is really what we care about, which is of course (power) x (time). For how long do you think that car is above the device? 3/4 of a second? 10 kW may be able to run a big microwave on 'high', but you can't heat up much of a dinner in 3/4 of a second! Time is a very important factor in the equation.

[f1000]

Originally Posted by Fyre4ce

Hypothetically, if you decreased the height of the road surface after the bump by, say, four inches, then it would work, but you would have to decrease the height of EVERY road connected to the bump by four inches, which is impossible because the road loops back on itself.

[tooki]

Originally Posted by Fyre4ce

Actually, tooki, I believe their numbers, but they are very deceptive. If a car generates 10 kW when it passes over the ramp, it's only generating that power while the car is on top of the device! Kilowatts is a rate of energy (known as "power"), and while the rate may be high, the total energy delivered is really what we care about, which is of course (power) x (time). For how long do you think that car is above the device? 3/4 of a second? 10 kW may be able to run a big microwave on 'high', but you can't heat up much of a dinner in 3/4 of a second! Time is a very important factor in the equation.

You are preaching to the choir. I understand the numbers -- electronics was my hobby LONG before I got into computers. My point was that their numbers don't make sense. I just didn't feel like going to the effort to spell out every detail the way you did.

The article says:

Dorset inventor Peter Hughes' Electro-Kinetic Road Ramp creates around 10kW of power each time a car drives over its metal plates.

That line, to me, is clearly mentioning an amount of time, therefore kW is a nonsensical measure, and that was my point. Either they meant 10kWh, which seems VERY implausible, or they really meant 10kW peak, which is, as you said, irrelevant and deceptive.

tooki

[Fyre4ce]

Originally Posted by f1000

Bingo.

[Fyre4ce]

Originally Posted by itistoday

I do see what you're saying, but I'm pretty sure that that's not the case. The car always had gravitational potential energy stored in it, and gravity does work on the car to push it down on the ramp as it goes down. The car's engine is not the thing that's pushing it down on the ramp. Read my above example of a rocket car in zero g.

Yes, but now since the car has sunk into the device, it must drive "up" the ramp a bit (once for each axle). It would be the equivalent of ascending a shallow grade for the split-second you are on top of the device.



LOOK PEOPLE - we are all missing the point of this "invention." The idea is not to somehow extract "free" or wasted energy from cars, or to create some perpetual motion machine. The idea is to remotely power traffic equipment. It doesn't really matter whether the car's engines need to work a little bit harder, because car engines are generally much more powerful than traffic equipment would require. So, maybe every time you drive over one, you use up an extra, say, half-drop of petrol, but is it really worth getting your panties in a bunch?

[itistoday]

Originally Posted by Fyre4ce

100% from the car's engine
0% from the spring
0% from gravity

Ok, after giving it some more thought I think I'm wrong. To explain the situation better to myself I came up with these examples:

In the event of a fixed, immobile ramp, if a car starts from a stationary position at the beginning of the ramp and climbs to the top so that it's just barely teetering at the top, all of the energy from the gasoline was used to get it up there, and then if it tips just a little over it'll come racing down the side and all of the energy it put in to getting up there will be "given" back to it making it go fast as it goes down the ramp.

In this case, we have a moveable ramp. You can think of a car, again stationary at the base of this ramp. It climbs to the top and teeters there, but by the time that it gets to the top the ramp has become depressed and level with the floor, so that when it "tips" over the top of the ramp, it does not move forward but stay still because it is now level with the ground. This way you can see that all of the energy that came from the engine to get it up there was "used" to push down the ramp.

So in other words I eat my words and take back what I said. *bows and disappears*

[production_coordinator]

What about motorcycles? These bumps look dangerous...

and what about snow/rain... the idea of driving over (riding a bike around, walking near) a 10kW submerged device seems exciting in a dangerous way...

Also, metal generally doesn't offer much traction... i'm sure they have thought of these things, but I just don't see this device working in many locations.

[Doofy]

Originally Posted by production_coordinator

What about motorcycles? These bumps look dangerous...

and what about snow/rain... the idea of driving over (riding a bike around, walking near) a 10kW submerged device seems exciting in a dangerous way...

Also, metal generally doesn't offer much traction... i'm sure they have thought of these things

I'm sure they haven't. This is Britain, remember. Very few of us here actually capable of rational thought.

[production_coordinator]

Originally Posted by Doofy

I'm sure they haven't. This is Britain, remember. Very few of us here actually capable of rational thought.

I was being serious... I'm sure they have thought of these issues, but I'm still at a loss for how well these would work with motorcycles, etc. etc.