That's a really great idea.

I agree, very clever

Finally

A great idea! It might be useful to generate electricity from pavements and subway stations everywhere... The major problem is going to be the initial capital cost, however.

But I like research like this - mankind needs to get its butt into gear, and make a paradigm shift w.r.t. energy. We need new and different ways of converting energy into useful forms, we need ways to better store energy, we need ways to conserve it, etc.

In this house we obey the laws of thermodynamics.

A few comments from SlashDot (not mine, but brilliant nontheless:

-------

Let's do the math:

* Let's say we can grab say one-tenth of a walker's energy without them caring.
* Walking takes about 1/20th of a horsepower.
* So we're getting 1/200th of a horsepower from each person.
* If we assume there's 1000 people walking by, that's two horsepower.
* About 1500 watts.
* That's about ten cents an hour. Given the variability of traffic, maybe a dollar a day.
* Assuming the mechanism costs a measly $100,000, at a dollar a day you can't even pay the interest on the loan.
* PLus it probably needs more than $1 a day of maintenance.
* Not a good idea.

-------

I believe that I saw an article on Slashdot several months ago where this kind of idea was implemented in Britain, but it was on the roads. Cars getting onto the highways would drive over large plates; the plates would move and generate enough electricity to run street lights. The First Law of Thermodynamics states that energy cannot be created from nothing. I believe that applies in Britain as well as the U.S., so the energy to power those plates came from somewhere. To wit, from the automobiles. The Second Law of Thermodynamics tells us that any time energy is transferred, some will be lost to entropy. Essentially such a device is A) using petrol in the cars to power the streetlights, and B) doing so less efficiently than would be putting petrol in the street lights and burning it there. It's a waste of fuel; indeed, a waste of dirty-burning fuel that creates CO2 (a greenhouse gas) and NO2 (smog). A horrible idea.

Who could possibly get away with wasting something so innovative by mistakenly placing it somewhere that nobody walks? Eight million people use the New York City subway system daily. Imagine if they put 'pads' in front of all loading areas.
You also have to consider that technology these days only needs a few years to dramitically improve in efficiency.

josh, true, everything runs to a state of equilibrium, but that doesn't mean we can't minimize entropy.

Whether you put the plates there or not, the same energy (or similar amounts) is being "lost." why not harness some of that energy and reuse it?


and josh, your example says it'll take 1000 people for 1500 watts. that's 10 people for 15 watts and 40 people for 60 watts. 80 for 120 watts. The article said a single person can charge 2 60 watt lightbulbs. so you're essentially underestimating the technology by a factor of 80.

and as deepchill stated, technology improves over time.