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Ramp Creates Power As Cars Pass
Ant wrote to mention a BBC News report on a ramp that generates power via passing cars. From the article: "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."
Takes generating electricity to a new level of inefficiency...
I suppose it might work on a ramp going down, but level or up, and the "free" energy is coming from the gas tanks of the drivers.
Jerry
http://www.cyvin.org/
No way I would avoid any roads with these, that energy the ramp "creates" it is really sapping from the vehicle. Heres an idea, since I was already taxed for purchasing the gas USE THAT MONEY TO POWER THE LIGHTS.
Just great. Yet another gas tax.
The higher the technology, the sharper that two-edged sword.
I wonder how long it takes to pay off a 25,000 pound piece of equipment plus installation and maintenance with savings in electricity for street and traffic lights? I'm guessing a really long time.
Is it even worth it?
when there is a red light ahead. so instead of wasting peoples gas, these things would save consumers brake pads?
so you could have a field of them that pop up some distance before each light to absorb all the wasted energy that goes into brake heat.
...or perhaps I should say, taxing gasoline *more*. After all, the power is coming from somewhere... you know, conservation of energy, and all that jive?
So, instead of tearing up the road, installing this infrastructure, and then paying to maintain it, why not just add 1 cent more of taxes to a gallon of gas, and earmark that money for the purpose of paying the electric bill? Seems a lot simpler. Besides, the taxes levied really ought to accurately reflect the full cost of utilizing the municipality's infrastructure... if this cost is something the bean-counters have overlooked in the past, just add it to the tax bill.
HSJ$$*&#^!#+++ATH0
NO CARRIER
What do you base your belief that this is "wasted energy" being used?
It's only wasted if the driver would have applied his brakes turning the forward motion of his automobile into heat. This would make sense on off ramps or downhill slopes. On a flat road, however, this will convert some of his forward motion into energy that this mechanism will leach.
The race isn't always to the swift... but that's the way to bet!
50kW is a big impressive number and all, but doesn't seem very useful. How much Energy does this produce per car?
The really frightening part is that the vast majority of the public will not grasp this concept in the slightest. They'll think of it as free energy and applaud it as it is implemented.
I wonder, why go to such extreme measures when the same money could be invested in A) a solar panel, and B) LED stoplights; a solution that would actually harness new energy from the sun rather than another system that would waste energy infused into fossil fuels by the sun over the course of many, many years.
They say it generates, on average, 10kW of power each time a car crosses. OK, great, but a watt is a measure of energy over time. So, for how long does it generate 10kW of power? Is it 10kW for a half second? 10 seconds? An hour? A millisecond?
If I have a 100W light bulb, how long can I power it off of the energy generated by one car crossing this ramp? With the information given, I have no way to calculate this. The "10kW" number is completely meaningless.
Energy is measured in joules, dammit. A watt is one joule per second.
So, this ramp generates 10kW when 'active'. Let's say you have a continual stream of cars so that it is active 50% of the time (since there must be gaps between the cars). This mean it's generates 5kWh of energy per hour.
/might/ just pay for itself.
/millions/ of cars passing over it.
Assume that the standard cost for elecricity is US$0.10 per kWh. So this thing can generate US$0.50 of electricity per hour. Over the course of a year it will generate about USD4000 worth. So after about ten years it
And that's not even considering maintaining the thing. Road wear out, and they're just simple concrete. This is a mechanical device, which will have
The whole things stinks of INVESTOR SCAM.
It doesn't have to convince us. It just has to convince some Junior-college educated city councilmen somewhere and the inventors are millionaires!
Currently hooked on AMP
That, and every bit of power generated by anything like this will be power removed from your car, so ultimately you'll pay for it at the gas pump.
Ultimately, the whole idea of car powered lights and such only makes sense if 1) it's in a rural location where power is hard to come by and/or 2) you want to slow the cars down anyways, like a speed bump (and others have already mentioned it.) Beyond that, implementing this sort of thing would not be cost effective.
From the look of the top picture in the FA, it won't do your tires or wheel-alignment much good either.
One line blog. I hear that they're called Twitters now.
My first gut, wet finger in the wind estimate as a thinking human with a technical eduaction is that this thing is total snake oil.
:-)
... to a rough approximation, this is constant regardless of speed, unless there is a traffic jam, because the inter-car gap is a roughly constant amount of *time* regardless of traffic speed - recall the mantra "Only a fool breaks the two second rule". Let's take that number....
.... drumroll .... 637W. For my fellow petrolheads, this is 0.85 horsepower :-)
:-)
Two issues with your approach:
1. You're forgetting the numbers are from a crazy optimist inventor who believes his own propoganda, is given to quoting unscientific data, and is trying like hell to sell his crap
2. I suspect your 50% duty cycle is way, way overestimated. My gut is that the 10kW is a theoretical peak for the fraction of a second an axle is actually passing over the ramp.
Take a different approach - let's figure out n upper bound on how much energy per car this thing could yield from first principles (reminds me of the Physics Part 1A Tripos at Cambridge, the short "back of the envelope" questions):
Suppose each axle ramps up and falls 0.1m when passing over it, that's roughly equivalent to the whole mass of the car doing so.
An average car in the UK masses 1300kg.
Gravity is 9.81 m/s^2
Total available energy per car is thus 0.1 x 1300 x 9.81 = 1275J
Now, let's figure out how many cars can pass over it in a given unit of time
1275J per car x 0.5 cars/sec = theoretical maximum output ceiling of
Average over a 168 hour week is going to be less than 1/4 of this, due to variability in traffic -> 150W or so.
Regardless of what timebase the inventor is measuring his 10kW peak over, he admits he is at only 800W on his own scale, or less 8% of what he considers maximum possible efficiency.
Applying that 8% to the above calculated theoretical maximum, we are down to a net average of 12W yeild from this thing, which is less than the heat being given off by the idle kitten sitting on my lap as I type this.
Conclusion - as we expected at first gut, total snake oil
It's not a win-win for people driving cares that already have regenerative braking.
The cake is a pie
As for the amount of gas it's going to use... A little bump like that should be nothing in comparison to some of the pot-hole filled roads I've driven through. It's no larger than a speed bump, and this sinks into the ground when you hit it.
:3 rawr.
How does he get 10KW out of this? That looks like an automotive alternator in the picture. Automotive alternators range from 300W to about 1.5KW, and that looks like one of the smaller ones.
A more reasonable mechanism would be to make a heavy duty rubber mat, like the ones used on railroad crossings, but with internal chambers, like a tire. When a vehicle drives over it, you'd get some compressed air. Put in a check valve, an air tank, and a small air motor driving a generator, and you'd have a rugged little power source. A hydraulic version of the system might produce more power output than a pneumatic one. The bump felt by the vehicle should be easier than that at a railroad crossing. And no big, expensive machined parts that get beaten up by traffic.
Realistically, get a solar panel, like CALTRANS uses to power much of their roadside infrastructure.
They talk about kilowatts, but for how long?... 1 second? 1/2 second? 1/100?
if it's 1/40th of a second as I would estimate each passing car would generate 0.069444 KWh and it would take about 50 cars to produce the equivalent of a fully charged AA rechargeable (if we take a 2500mAh battery). But I guess their marketing department wouldn't want us to learn those number first...
This is NOT energy that'd just be lost. And it's NOT waste.
If they put this out on open roads or uphill grades (ramps, etc), then it IS theft.
If they put this on downhill grades (also ramps, etc), it's STILL theft. On places where people need to stop, people using regenerative braking will lose some of their fuel savings (when they're already having problems recouping the price-premium of a hybrid). On straight downhill stretches where no stopping is needed, they're increasing the wear and tear on the suspension, tires and requiring the car to expend energy it would otherwise not spend (coasting) to traverse the same distance.
All this energy is coming directly from increased fuel consumption. So it's NOT good for the environment (increased emissions and all).
So no. It's NOT money in the bank. It's money out of our pockets FOR GOOD.
Unless you want to somehow claim this device violates the Second Law of Thermodynamics....
Chas - The one, the only.
THANK GOD!!!