Materials for a piezoelectric flooring test with footsteps

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The Christian Science Monitor is certainly a reputable source. Please stop posting such nonsense.
 
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Wreak_Peace said:
They never mention piezoelectricity... They mention a fluid, which when compressed will create an electrical current.

True, but the only working device that MIT students have built (according to the your MIT link) didn't involve piezoelectricity either. It was a stool with a built-in dynamo that powered 4 LEDs.

The point is, the "waste" energy from humans is not mechanical, it is heat. The heat energy available from a the feet has been measured at about 20 watts. If you want to make an efficient way to collect heat energy, you build some sort of heat engine. That's what the guys from Madison are doing, though they are also using the mechanical pressure from walking to help pump the working fluid around, so far as I can understand their website.

If you think about impedance matching and the maximum power transfer theorem, it seems rather obvious (to me) that attempting to transfer mechanical energy from a walker into the floor, before you convert it to electrical energy, will have a very low efficiency, except perhaps in two cases:

1. You make a very flexible floor, which will be difficult and tiring to walk on.
2. The "walkers" are actually jumping up and down (with straight and stiff legs), which might account for why a similar system "works" in a disco. But I'm much too old to know first hand what goes on in discos these days!
 
AlephZero said:
If you think about impedance matching and the maximum power transfer theorem,

I totally understand this...
(Sarcasm, but I do get your point, its not efficient)

But I'm a stubborn person and you'd have to admit that it wouldn't be that inefficient in the busiest areas of an airport (Security Checking, Baggage Claims(Possibly on the baggage claim carousel itself?)) ..
It could also work underneath busy roads, or sidewalks, in New York..

I mentioned this earlier, but underneath takeoff/landing strips there is a potential of a lot of energy, just that it needs to be very flexible and deep underneath the stone.

It'll be really small, but in really busy areas, wouldn't all the tiny footsteps add up?
I kind of made it into a fermi question involving Atl. Hartsfield Jackson, but I'm not that good at them..

And sorry for claiming that the Christian Science Monitor is unreputable, I was just going off of what somebody else said.
 
Wreak_Peace said:
I kind of made it into a fermi question involving Atl. Hartsfield Jackson

Except that you refuse to accept the answer.

This thread is done.