piezo-electricity

[pj83]

I'm new to electrical engineering so this is probably a stupid question. But after reading about piezo-electricity, can it be applied to large structures, like a bridge, to generate electricity when traffic travels over it ?

[berkeman]

I'm new to electrical engineering so this is probably a stupid question. But after reading about piezo-electricity, can it be applied to large structures, like a bridge, to generate electricity when traffic travels over it ?

Welcome to the PF. Not a stupid question at all. We had a similar thread someplace here on the PF recently. Bottom line is that you don't get any free energy out of it. The energy that you could harvest from deforming (banging on) a piezo or other roadway would come from extra fuel burned in the cars.

[pj83]

Yeah I suppose thats true, I've read that piezo inserts in shoes could be used for powering mobiles and the like. Could'nt the same technology collect energy from people walking on pavements in busy streets ?

[negitron]

Same deal: the energy for that comes, ultimately, from the food the pedestrians eat.


Though given the weight problem this country suffers, it might not be a bad idea.