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Got a funny idea about mechanics a couple of days before. I guess there is some sort of fake logic in these arguments, but I just can't find any counter arguments or simple explanations about it.

Lets imagine some static large tall truss farm structure (like transmitter towers). Also lets say it is axisymmetric and heavy enough to create high loads on lower levels.

Lets attach to deformable trusses a special piezoelectric elements (just same as in the piezolighters) with the ability to create electric charge at both compression and stretching. They are all wired to some electric grid.

Additionally lets install some wind stopping load on the top of this installation (let it be some large cube).

Since the structure is axisymmetrical and is loaded by wind randomly, so all the trusses with piezoelements will experience random cycles of compression and stretching. With each cycle they will produce some electric charge which can be gathered and collected in attached electric grid.

So in general we can get an infinitely scalable power generating structure, just increasing the weight of structure and number of piezoelements.

Does that means it is a kind of almost infinite energy source, based on gravity and the forces of support reaction from planet surface ? Is it a conversion of gravity to energy, or just something else ?

Also lets imagine a planet/satellite (like Moon or Mars for example) and built in very large structures on it like these ones, generating power and sending it to some remote location. What about the law of energy conservation ? Where the energy is taken and what will happen to that planet in time - will it slow on its orbital movement or something ?

I guess there is some kind of logic/physical paradox in these ideas, but just can't find any obvious mistakes in it. Could you please comment it ?

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  • $\begingroup$ Is there a question here? Also, just a FYI, the energy recovery on such a device is probably extremely small compared to the energy transmitted by the wind loads. Plus, situations like steady wind in one direction wouldn't be efficient at all. It would take some analysis of wind direction averages to determine if an omni-directional wind is really beneficial. Given that I see wind farms always facing approximately the same direction, I don't think an omni-directional approach is that effective. $\endgroup$
    – JMac
    Feb 26, 2019 at 21:14
  • $\begingroup$ Well, we can almost infinitely increase an overall energy output by increasing structure weight and number of piezoelements per truss. Steady wind will provide turbulence and fluctuations that can be used with small piezoelements. $\endgroup$ Feb 26, 2019 at 21:19
  • $\begingroup$ The question is about why this kind of structures are not possible or not produced now $\endgroup$ Feb 26, 2019 at 21:21
  • $\begingroup$ I suspect if you work out the power generation it won't be much, but it is inventive! $\endgroup$ Feb 26, 2019 at 21:23
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    $\begingroup$ Such questions aren’t really on topic here. Evaluating the feasibility of such things is outside the scope of the site. $\endgroup$
    – JMac
    Feb 26, 2019 at 22:04

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the power output (voltage x current) of even a very large array of piezoelectric elements is tiny, since the actuation is very poorly coupled to the generation means, and not worth the effort to harvest in this way.

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  • $\begingroup$ Lets take a look at ordinary common piezoelectric lighter. The igniting piezodevice is quite small in size, but it produce enough energy (compared to a battery of same size) to ignite a fuel. The ability to produce power is roughly proportional to a volume of piezoelement. So it means to be scalable and easy to increase total output almost infinitely. $\endgroup$ Feb 27, 2019 at 10:30
  • $\begingroup$ The idea in general is to produce electricity with piezoelements in common elastic or heavy loaded mechanical systems with random load or dumping function - including car tires, buffers, dumpers, footwear soles, etc. Take a look at simple list of possible applications link $\endgroup$ Feb 27, 2019 at 10:38

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