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."

Comments

How much power?

[rob_squared]

Does a tractor trailer give it? Or would that break it?

Re:Great idea!

[MemoryAid]

It looks like a speed bump, so presumably it is to be placed somewhere cars are encouraged to slow down. It would make sense to convert some of that energy into electricity instead of heat.

The article said that "Depending on the weight of the vehicle passing overhead, between five and 50kW can be generated." I wonder if that is only while the car is passing, or an average figure for some reasonable level of traffic. I imagine the duty cycle of a speed bump is low.

Re:Great idea!

[aXis100]

Uhh, no. Wheels do not transfer energy (primarily), they transfer force. Force times distance (your wheels turning against torque) equals work (energy), so by wheels turning they convert the chemical energy of the fuel into kinetic energy of the car.

The only other significant energy wheels transfer to the ground is a bit of hysteresis and some skidding.

Re:Noooo way

[BLAG-blast]

No way I would avoid any roads with these, that energy the ramp "creates" it is really sapping from the vehicle.

I assume you mean you don't want to drive on the roads with these 'ramps'.

Heres an idea, since I was already taxed for purchasing the gas USE THAT MONEY TO POWER THE LIGHTS.

That brings up an interesting point. Maybe, I'm paying tax on gas to power traffic lights in your town? (I know taxes are a little more complex than that, but....) How about the people who are using the traffic lights pay for them? That sounds pretty fair, right? If you live on a street that has few traffic lights, why should you pay taxes for three streets over to power x5 the number of traffic lights when you never drive there?

This would make the lights powered by the people who are using, rather than by people who are not using them.

Re:The obvious question is

[interiot]

http://en.wikipedia.org/wiki/Regenerative_braking

Basically, put these things in places people would always slow down anyway (eg. off-ramps), and it's a win-win. Free energy production for the city, and reduced wear on brake pads for the citizens.

Lots of Negativity Around This Story...

[RoffleTheWaffle]

... And for what?

Okay, okay. I get the idea, this is essentially a means by which electricty can be derived from the same energy that drives your vehicle. However... isn't this energy that would just be wasted, anyway? This thing doesn't exactly slow down your car. It's not like it's sucking power right out of your engine. This is kinetic energy combined with the force of gravity and the weight of your car, energies that would just be wasted and poured into the ground otherwise. Ten kilowatts, depending on your perspective, may or may not in fact be 'drops in the barrel' energy wise, but it's more than enough to power devices like stop lights and road signs, granted it's stored efficiently and the devices attached to it are similarly efficient.

On a well traveled road, energy that is essentially being wasted can be recaptured and used to power lights and signs for several intersections without placing any load on the local power grid. Sure, these things are pricey, but as their price decreases with time and their efficiency and output both climb, doesn't it make sense that these things just might pay for themselves? That reduces the cost of maintaining roads in the long run by cutting out virtually all energy expenses in areas that are frequently traveled - and if the system becomes efficient enough, it could cut out the energy costs for an entire community's roadways and intersections.

This isn't 'another gas tax'. This is one less reason to have gas taxes. On a highway like ol' I-69 here in Indy, a couple handfuls of these ramps could power every lighted roadside sign and traffic signal within the city of Indianapolis, with energy to spare. Higher traffic translates directly into greater energy gains. If these things are durable enough to take the punishment, they'd pay for themselves within a matter of weeks. Now let's think about even more heavily traveled roadways, like those in New York City or LA. 10 kilowatts per panel times a few thousand automobiles a day, that's megawatts and megawatts of power being generated every day. The excess could be put into the city electrical grid, however small an amount it may be by then, and used to power other things. Street lights, low-demand municipal facilities, etc... All of this from WASTE. This is an excellent idea, and I hope to see technology like this move forward.

And before anyone replies to this, no, this is not 'just another way for the government to control our cars'. I won't be concerned about that until they start installing spike strips in these things. (And with or without ramps, that could be done at every intersection anyway....) This is hardly ripping off the taxpayer, either, if a comparatively small expense saves a ton more money. Sure, right now that expense isn't small, but it'll get smaller if enough communities buy into this stuff - perhaps even going from a few thousand dollars to just a few hundred. Money in the bank, and back in our pockets, folks... No problems here.

Solar Panels? In Britain?

[billstewart]

There are parts of the British Isles where solar panels might work. There are other parts, especially in Scotland, where using solar panels would require seeing the sun, and therefore are obviously out of the questions. The typical local description of the weather runs to "If you can see across the bay, it'll rain within 24 hours; if you can't see across the bay, it's already raining."
Sure, some parts of the year it's sunny and beautiful, but you need the streetlights to work all year around, *especially* when it's foggy, raining, and dark. So you might need some pretty big panels.

On the other hand, these ramps probably cost a big enough pile of money that it's still cheaper to use mains power than "free" power siphoned off passing cars.