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toothdust
12-12-2008, 05:11 PM
Japan harnesses energy from footsteps (http://www.telegraph.co.uk/earth/energy/3721841/Japan-harnesses-energy-from-footsteps.html)

Ingenious. There really is energy to be had no matter where you look.


Experiments have started this week at two of the Japanese capitals' busiest stations, with special flooring tiles installed in front of ticket turnstiles. Every time a passenger steps on the mats, they trigger a small vibration that can be stored as energy.

Multiplied many times over by the 400,000 people who use Tokyo Station on an average day, according to East Japan Railway, and there is sufficient energy to light up electronic signboards.

"We are just testing the system at the moment to examine its full potential," said Takuya Ikeba, a spokesman for JR East, adding that the tiles are constructed of layers of rubber sheeting, to absorb the vibrations, and ceramic.

mugaliens
12-17-2008, 11:44 AM
They ought to create down escalators which are little more than generators powered by human weight.

When it comes time to go up, let the masses walk up the stairs - it's good for them.

toothdust
12-17-2008, 07:16 PM
They ought to create down escalators which are little more than generators powered by human weight.

When it comes time to go up, let the masses walk up the stairs - it's good for them.

Completely agree!

A.DIM
12-20-2008, 09:34 AM
Yeah, this is cool stuff.

I've read where they're looking at using the heat & vibration from asphalt pavement in similar fashion.
Makes perfect sense considering how many roads with vehicles on them...

mugaliens
12-20-2008, 02:03 PM
Yeah, this is cool stuff.

I've read where they're looking at using the heat & vibration from asphalt pavement in similar fashion.
Makes perfect sense considering how many roads with vehicles on them...

I'm wondering if it wouldn't be better to simply make harder, smoother roads, and tires with higher pressures, thereby eliminating the transfer of energy in the first place. Consider trains, which use steel wheels on steel tracks - it's the lowest rolling friction around, much less than that of hovercraft.

All energy generated by "pressure" is really a force moving through a distance. It's just the equation for work: W=F*d Power is the rate at which work is done. Thus, a force of 1 lb applied over a distance of 1 ft is 1 ft-lb of work. If that's done in 1 second, then the Power is 1 ft-lb/s, which equals 1.3 watts.

But if the roads are hard, less energy is loss to rolling friction in the first place, no distance is involved, and thus no power can be extracted. But that's a good thing - as no power is wasted travelling over a soft road!