Um, except that any energy produced by the generator is going to be less than that wasted by each individual car in pushing down those plates... Basically they're just forcing their customers to pay for a really inefficient generator...

And costs millions to implement and maintain. I've got a better idea. Skylights and solar powered calculators. Problem solved.

At least they're trying.

@Josh : missed the point there, sunshine. As long as the customers are going to drive in anyway, every bit of their potential energy recovered is a bit more available for general consumption, or not needing generation by unsustainable means. By using this type of pressure generators it's also not tied to any specific fuel driving the weight (the cars) over the plates, so it's futureproof as well. This could easily be implemented in speedbumps. -*thumbs up*-

@djc: missed the facts there. The plates will require extra energy to push down and drive over, causing the car to expend extra energy.

It makes more sense to burn coal in a plant and send the electricity over the wires, as it would do less harm to the environment, and waste less energy. Probably cost a lot less too.

Science education is woefully short these days.

Cash registers powered by fossil fuel. Wow. I guess the illusion of being "Green" is more important than the reality.

Why not use this same tech. and install under the floor boards in our kids rooms? The solution to the energy crisis... an infinite supply!!

people seem to be slightly confused here. I know none of you have done the math because they do not provide the figures. The fact is that there are 2 things happening here. A slight (probably) increase in fuel use to go over the plates, and GRAVITY. You see there's this thing called GRAVITY that pulls things down. In this case GRAVITY pulls the car down onto the plate. WOW! That's right some of the mysterious GRAVITY energy is transferred too! O.O

Thank you, nicholasjh.

It's really funny to be taken to task by the likes of Volition and Josh, when there is no possible way for them to back up their snark with anything remotely like facts.

:^)

@Erebiel, @nocolasjh, et al. For GRAVITY to work, the cars must first go UP. For them to do go up, their wheels have to exert a little extra torque for each bump, burn a little more fuel, and lift them. Gravity doesn't come for free when you're starting on the ground as these cars would be. Now: If the parking lot were _already_ on a hill, it might be neat to have a "down lift" that would let cars' gravitational energy do something on the way down. @Josh et al.'s logic is simply common sense, and doesn't require numbers: You're harnessing energy from something by first requiring that it lift itself.

Wow, I read this and all I see is "30 KW of energy an hour"... *sigh*

wow, this is what you get when you give little to no specific information...
anyway, from that sketch, it's obvious that the plate is UNDERground, (much like a trafficlight sensor works, or, a dancemat for your gaming console) so the car does not "climb" anywhere, rather rolls over, so i'm throwing my hat on the POSITIVE pile on the basis that it would be the energy generated by the weight of the car pushing down. This action requires no energy whatsoever on the part of the car, only the positioning of the car on top of the plate (the act of driving to the shopping mall, which would take place ANYWAY) does. If the movement of the plate is not beyond the movement of the suspension of the car, it wouldn't even be noticed. Depending on the speed of the car, the entire sequence (car going over the generating plate, pushing it down, turning the generator) is over in less than a second !

I really don't think this works.

The car does "climb", it has to mount the speed bump esque plates, this will require more energy then normally driving the car, unless of course it's completely frictionless (we can hope).

I won't speculate on how efficient it is, as I don't know the figures, but it definitely will require more energy from the car then usual, otherwise the energy crisis is solved and we would have breaking news.

I'm not sure why everyone here seems to be talking about spending extra energy driving up on some raised plate.

It was a fairly short article, and nowhere in it does it mention gravity or pressure. It says that the plate rocks forward and backward as a result of you stopping on it.

It is a conservation of the extra wasted energy people already use by driving too fast through the parking lot. If you slowly coast into on of these spots, very little energy would be captured.

That being said, the whole thing seems extravagant and expensive just to save on utilities. You would be hard pressed to tell me that the long-term cost of this system is cheaper than solar, wind or conventional electricity.

Really, if you do not have an engineering/physics background, do not try to argue or assume anything. This would not work.. basic energy balance. The energy has to come somewhere, and /gravity/ is not a source of energy, only a medium to convert potention energy to kinetic energy. Add in the inneficiencies of mechanical and electrical systems, and we are consuming FAR MORE energy than we are CONVERTING.

If you don't understand that without me getting more detailed, then you should not be writing your opinions anyways.

and the first thing I noticed about the article was '30 KW of energy an hour'.. and it made me sad. Who writes these articles?

@geoncic: There's really no reason to be rude to people wanting to post their opinions. Even if someone doesn't fully understand, they have just as much right to speculate as someone else.

Now, again, I'm not sure why you would say this couldn't work. There seems to be two conversations happening: people saying it won't work, and people saying it is inefficient.

While I fully accept that it is inefficient, the concept is easy enough (and I DO have an engineering and physics background).

There is a simple demonstration that anyone here with a car can try - it's safe and easy to do. It will show you where the kinetic energy is coming from for this parking lot generator. Take your car somewhere (side street/parking lot) where you will be able to stop abruptly. Get your car up to 10 mph and then apply the breaks.

Even at this speed, your car will shift forward during breaking, and then shift back. This is energy that most people are expending already.

I may have misspoke before about the car not pushing down on the plate - it does push down, but as a component of the kinetic energy of the car and the force of friction on the tires.

You don't have to take my word for it, but it seems like an expensive system to install if it didn't work at all.

The energy comes from reducing the speed of the car, so is not 'free' but really from the car's fuel tank.

They can only get green credentials when replacing existing speed bumps or in areas where cars already slow down on the brakes wasting energy as heat (e.g. stop signs, car park entrances etc).

Of course if you drive a car with a regenerative braking system, you've just given up energy that you could have reused to power your car. I guess its a numbers game to see which has the best efficiency - car or road.

Unsavoury organisations could of course just string a bunch together on a deceptively flat and unimpeeding road just to steal energy from cars! But I'm sure supermarkets have a high moral fibre content and wouldn't do that.

Maybe these are being installed where the store NEEDED speedbumps anyway, for the safety of the pedestrians in the parking lot. Then, they would be harnessing an additional expenditure of energy, but a necessary one. There isn't enough information here for proper conclusions, but clearly, they're moving in the right direction.

The kinetic energy loss is probably very small, so small I'd compare it to the bell at a fuel station.

More problematic is how much will this generation system cost in maintenence. Is it cost effective for the store? If it is cost effective this kind of system should see widespread use. Its too bad it'd take too much wear and tear on an interstate highway though.

And the elitist comment of the week award goes to:
"Really, if you do not have an engineering/physics background, do not try to argue or assume anything"
First of all, wrong forum. Keep validation of academia in the halls of academia. This is just a comment section on a gadgety website. People will get it wrong, will assume wrong things, will say out loud something *facepalm* -esque, but all that's fine.
Everyone has to have the right to speculate, in the history of the world there has never been significant progress in science when some instance has deemed discussion reserved to a specific group to which only they and their pals belong to.
If just one kid goes away from this fairly vague description of a system to recover energy, and it lights a spark at the back of his/her mind, and a few years from now a new, improved system arrives , how great would that be!

I'm sorry if i come across offtopic or harsh, but that attitude rubs me the wrong way. Have a nice day!

@volition You forgot that the cars weight due to gravity will move the pads

Why not just inconvience your customers more by making wear plug in shoes with those little pezo devices in them. Additional, you would need any lights with all those little red flashing lights going off.

I GOT, I GOT..; Lets make the floor of the store out those motion bump things and we'll feed all the customer coming sample of bake beans. We can get the power of the customers shopping and harvest the methane to boot.