Sound Waves To Electricity Generation

[Epower]

If a wall of "sound-a-volt" generator cells 200 feet long x 15 feet high were installed along side of an airport runway or along the sides of a subway tunnel, it could produce an output of current of 120 amps x 20 volts or 2400 watts of power. Here are some numbers, 200ft, x 15ft.= 3000 x 144 sq. inches x 2 = 864,000 sq. inches. Each "sound-a-volt" generator cell (which is a 5-cell unit) requires an installation area of 36 sq. inches. which when divided into the number as noted above =24,000 cells in all. Each 5-cell unit will generate a current of approximately .005ma x 24,000 cells =120 amps. x 20 volts or 2400 watts of power. If the output voltage of 5-cell unit could be increased to 110 volts, the output would be 13,200 watts of power (120 x 110 = 13,200 ). This is just an estimate of the possible power that this "sound-a-volt" generator system could produce and more. Not bad for something that produces such a low current per cell unit, but when multiplied look what happens...Never overlook the small....Epower

[jomoco]

Sounds interesting, what's the cost to benefit ratio? Can it fly economicly?

jomoco

[jimovonz]

You are kidding right??? Assuming your figures are correct and you can make 2400W from your wall, your typical jumbo jet will go past pretty damn quick and the next one won't be along till its off the runway. Maybe you'll get 1 sec output every 5 minutes or about 0.2kWh/day. Maybe you'll get a bit more if the wall is on the taxiway - but the jet won't be as loud. How much do you think your 24,000 cells will cost? Have you ever seen the effect of the wake from a jumbo jet? The structure to hold your wall up will be huge...

Now lets assume your figures are incorrect. 120db is the threshold of pain for humans and represents 1w/m2. Your wall is approx 280m2 so with 100% efficiency you could expect 280w. The jet may be louder even than 120db, but I doubt that as your wall will only be to one side of the jet, not at the rear where it is loudest.

You would be much better off by a couple of orders of magnitude by putting all your effort into building wind turbines next to the runway to catch the turbulence. Heres one, try 24,000 PV cells...

I applaud your efforts in experimentation but you are never going to make much power from sound for the simple reason that there is not much there in the first place. Your super sensitive ear just tricks you into thinking there is. There are a lot of devices/ways to capture much more energy (especially if you have 24,000 of them)

[Epower]

Hi Jimovonz, Experimentation is what its all about and only time will tell. In the past, they said the same thing about electricity what good is it and who is going to use it. All great dicoveries started with an idea or a dream and only persistence and hard work made it paid off. Sure I could choose to build wind generators or solar panel arrays, but I like to challenge the almost impossible along with building what does not exist. I have always like the challange when people like yourself say, what good is it or you will never make much power from sound. I thank you for your input, but I will still keep on trying. One day in the near future I might prove you wrong....It might not have the power of the genny, but some power is better than none and it new. Anyway this is a great site to be on, even if we don`t always agree. Good feedback is what its all about and without it we would still be in the dark, so to speak......Epower

[stop4stuff]

Hi Epower,

I understand where you're at...

another good location for your 'sound-a-volt' wall would be in tunnel or bridge walls (roads and railways.)

epower, is the output figure correct, 0.005A, or 0.005mA (0.000005A)?

jimovonz, if epower's output suggestion of 20v x 0.005a per 5 cell unit is correct, then his unit already surpasses 1w/m2... 1m2 ~= 1521 sq.in., this area could accomdate 42.25 units, each unit putting out 0.1w, 42.25*0.1 = 4.225w per m2

paul

 

[wooferhound]

So you get 20 volts at .005 amp per cell, but at what volume, decibel level?

I really think that you would get more power from a 12 inch speaker than from piezo elements. The voltage won't be as high, but the amps will be way higher.

[jimovonz]

After re-reading my post I think I was being a bit harsh - I shouldn't be so discouraging (though I don't believe there is anything wrong with the figures I quote).  I wish good things come from your endeavours

[Aelric]

another great location besides airports (in my humble opinion) would be heavy metal concerts hehehehe.  

Tunnels and overpasses would be good, there are lots of great places to find wayyy too much noise, I work in a metal fab plant and we have turret presses and a 520 ton press and a 300 ton press, when they get going it gets pretty loud and stays that way till they finish the order.  My point is factories, airports, tunnels, big cities, there are tons of places with a whole lot of sound pollution and I applaud your efforts to harness it, would love to hear more about it.

[Jeff7]

Count me in the group that says sound doesn't have much power. Think of the power that is required to let you hear a sound - moving air molecules need to move your eardrum a fraction of a millimeter. That doesn't really take much evergy at all.

Or a microphone - the little bit of current it produces must be amplified immensely to be useful. A collector would need to be huge - expensive - and be placed next to a steady source of noise. A subway or airport doesn't really count, as the traffic going through is 1) artificial, and 2) not reliable. Using energy from an artificial means like that could be bad, because what if someone invents a great new way of making near-silent subway cars? Will there be lawsuits from the Sound-to-Electricity Association?

I'll also say that the money used to research/build a massive sound collector could be better used for research on new battery technologies, new PV methods, or else more wind/tidal generators.

But at least you're looking at collecting energy in an environmentally friendly way - solve it that way, rather than just say "Yeah, energy production is simple - just drill for more oil and burn more coal."

[Epower]

The subway system here in Toronto, Canada is a very busy place. Our subway train passes every 5 mins or so during peak hours and from then on every 20 mins or less during off hours. Thats alot of unused power that you could tap into. The wall of sound-a-volt cells requires one of two things, a noise of some kind which is a sound wave or even the air pressure of a passing subway train, would create a huge oscillating pressure wave causing each of the cells to generate a current and from there stored into a battery bank or capacitor bank to be used when needed or even back to the grid, which would reduce the operating cost of the subway system. It does not matter if the subway train were designed to be silent or not, it will still generate an electric current. A subway train is at least 10 cars long or more depending on the city. That wasted power should go to good use and not to be forgotten. The only way we are going to feed our energy needs is to come up with new ways of producing clean energy. This requires an open mine, time and alot of hard work......Its easy to say it won`t work, thats what most of us do, sit back and let someone do it for us. Why not take on the challenge and work with thoses people who are trying to make a difference....Epower

[Cuteepikur]

What about the oceans?

I spent the Easter weekend at the shores of the Baltic Sea where the weather was rather bad. Strolling along the shore and contemplating what kind of catastrophes could lead to a tsunami there I suddenly realized how load the Sea actually was.

Of course it sounds like a nice idea to decrease the energy consumed by subways and the like by feeding some of it back into the system. But obviously this can never be a real 'source' of energy.

To me the oceans, at least the rough parts of them, seem to be a very rich natural supply of sound waves.

[commanda]

Each 5-cell unit will generate a current of approximately .005ma x 24,000 cells =120 amps. x 20 volts or 2400 watts of power

Slow down there. 0.005mA x 24,000 cells is 0.12 amps. You're out by a factor of 1000.

Amanda

[Epower]

Hi Amanda, Each unit generates 5ma x 24,000 cells which = 120 amps or 2400 watts of power as noted in previous postings. I did not state that it was in the microamps (u) range. The symbol "milli", a prefix meaning one-thousandth. (24000 x 5ma = 120,000 ma`s divided by 1000 which = 120 amps ) So you are telling me that I have only an output of 120ma`s (or 0.12 amps)., If you recheck the numbers 24000 x 5 does not = 120 . So I believe that you are out by a factor of a 1000....Epower

[commanda]

Each 5-cell unit will generate a current of approximately .005ma

Obviously you made a typo in your original post.

5mA is 5/1000th of an amp.

.005mA is 5/1000000th of an amp or 5uA.

I think what you meant to write was .005A.

BTW, sound pressure, if I remember correctly, falls off as the square of the distance. That is, the distance between the source and your cell will have a large inpact on how much power you actually get out of it. The specification sheet for the cells should quote an output at a given sound pressure level, usually in dB, and referred to some reference sound pressure level. Have a look at speaker specifications to get an idea what I'm talking about.

Amanda.

[Epower]

Stand to be corrected:  Noted, I meant 5mA ( .005A ). Thanks for the input.....Epower