Converting noise into electrical energy

[kthouz]

Hello everyone!
I have an idea of making a device that can convert noise into electrical energy.
In many fields (industries, cars, construction machines,...), some used machines make much noise, then I thought as sound (noise) causes mechanical energy, why not convert that mechanical into electrical energy as microphones do to convert the sound into electrical signals? But here, i would like that device to be more efficient than a microphone.
So if anyone worked on the same project or knows something about it that can be helpful, please let me know.
Thank you.
I will be posting here what I've done so far.

 

[vanesch]

You should first do an estimate of how much energy is available from the sound noise.
I think you will find ridiculously small numbers.
And then wonder whether there's any point in making something that can get out this energy.

 

[Andy Resnick]

Also, if the noise is 'noise' (i.e. energy that has been dissipated), there's no way to convert it back into energy available to perform work- 2nd law of thermodynamics. See, for example, Feynman's discussion of the ratchet and pawl.

 

[DrZoidberg]

The 2nd law of thermodynamics applies to heat and not noise. Noise can be converted to electricity but I think it's pointless since you would only get very small amounts of electricity.

 

[Andy Resnick]

The 2nd law pertains to entropy. A noisy signal has a different entropy than a coherent signal.

 

[A.T.]

I bet you could create some useless gadget like noise powered blinking earrings for the techno-club.

 

[vanesch]

The 2nd law pertains to entropy. A noisy signal has a different entropy than a coherent signal.

Yes, but I think what you are referring to is "thermal acoustic noise", and a noisy machine has quite more noise than the thermal noise which is limiting sound registration for instance. This is like white light, which is also electromagnetic noise, but if its energy density is larger than the thermal (black body) electromagnetic noise (radiation), you can still extract energy from it (with photovoltaics, for instance).

However, the energy of acoustic noise, even if it is "loud", is still quite small, so, it would not be very useful (but the earrings might be an idea )

 

[Loren Booda]

I would foremost consider a magnetic damper (e.g., a magnet and a coil mounted on relatively vibrating surfaces) that generates current.

Also, a putative model for a Maxwell's demon, of which there are many applied to "thermal acoustic noise," could more realistically be modified to your purpose.

 

[Ranger Mike]

Hello everyone!
I have an idea of making a device that can convert noise into electrical energy.
better yet, convert noise into MONEY
Dire Straights did a song..Money for Nothing and Chicks for free...
seriously..i applaud your idea

 

[Andy Resnick]

M<snip> This is like white light, which is also electromagnetic noise, but if its energy density is larger than the thermal (black body) electromagnetic noise (radiation), you can still extract energy from it (with photovoltaics, for instance).

<snip>

That's a really excellent analogy, thanks!

 

[kthouz]

Thanks for your ideas.
That was my idea too, and i did consider the electrical signals collected by a microphone which have to be amplified in order to be put through speaker, noise should not be really efficient to give an important electrical energy.
But, meanwhile, i have been googling and i found a device that has been made "sonea" which is used to convert noise of huge machines into electricity.
Anyway, i will still looking for another thing to work on (related to physics specially material physics or renewable energy"? Is anybody got something else, please let me know.

 

[Beanobops]

Lads great idea with the noise... I work for a roads dept and am currently looking into this... we were looking at noise mitigation noise barriers... and decided to take it one step further and maybe steal some energy if possible... the "sonea" website was a great start thanks for that kthouz... these roads would be busy 30,000 vehicles per day with noise levels on properties of around 70dB peak times... so represent a way of capturing energy from the traffic... Is this a feasible idea or am i just wasting my time in terms of energy generation?

 

[sophiecentaur]

A tiny fractional increase in the efficiency of the original acoustic noise source would represent much better use of the original energy source.

 

[dhairya]

i think this idea for producing energy may be feasible but it can be better in removing noise energy. i am working on noise cancellation and i think by converting noise into electrical energy it can be removed by filters.anyway good luck for your work.

 

[sophiecentaur]

The flux of sound energy at the threshold of hearing is 10^-12 W / m²
If the sound levels you are dealing with are, say 80dB, that means you would expect only 0.1mW of energy for every square metre of any system used for collecting this noise energy. I think that gets things in proportion. It may be 'almost deafening' but there ain't much actual energy available. Even at the 'threshold of pain (120dB), you'd only get 1W per sq m.. Compare that with a solar cell in cloudy conditions in Winter - and a solar cell is giving you actual electrical power - your sound energy reclamation device would still have to do some energy conversion to electrical, with I've no idea what efficiency.

 

[dhairya]

i dnt want to convert noise into electrical energy for reproducing energy. But if i convert noise into electrical form than i can use some electronics things to remove noise. My application of this conversion is for removing noise in apartments or dense area which generally comes from window so i want to make something which removes noise with opened window.thanks for reply.

 

[exilus29]

can sum1 give or enlighten me with "sonea". we have a feasibility study and our topic is about harnessing sound energy to electrical energy.we are having a hard time but we can't back up now.can sum1 help me with this topic?any1 there who could help me please do

 

[willem2]

It's hard to tell you, since the only info about the "sonea" in the english language was written by someone who doesn't know what a dB is and who confuses power and energy.

 

[exilus29]

^sir willem2 do you have an idea about sound to electrical energy?we want to at least light a LED

 

[kthouz]

can sum1 give or enlighten me with "sonea". we have a feasibility study and our topic is about harnessing sound energy to electrical energy.we are having a hard time but we can't back up now.can sum1 help me with this topic?any1 there who could help me please do

whatelse i could know about converting noise into electricity is about the "piezoelectric effect". Sonea is just a device which was designed (based on piezoelectric effect per harps) for that task but the website where i found it did not have any physical principle of it. Just try to google and see if you can find something

 

[exilus29]

how far did you try to make a circuit that can convert sound to electrical energy

 

[kthouz]

i didnt do anything else apart documentation. I talked with the one whom i wanted to be my supervisor and told me that it is a higher level project and that it was not more efficient in my country. But what i know the key is about the piezoelectric effect. And furthermore, any vibrations (mechanical energy) can be converted into electricity through a transducer. This is even how microphones work. I wish i can help you as i can.

 

[exilus29]

wew that is our big problem our thesis is about sound and our dean/prof is strict about the title that we can't use vibrations as an alternate for the sound energy

 

[kthouz]

look, i have a friend who is working on a microphone, i will ask him and tell you more details, coz i think your project seems to be a modification of a microphone because you will be dealing with louder sounds (eg. from industries' machines) and you will not need higher amplifiers, right? Here is my email address if you still want to contact me giray03@yahoo.fr

 

[exilus29]

thanks for that...yes i really need sum1s advise we are lacking out of time and I am only a student need sum1 who has more knowledge about this topics add me up>soulstriker29@yahoo.com

 

[amit9203]

Hello everyone!
I have an idea of making a device that can convert noise into electrical energy.
In many fields (industries, cars, construction machines,...), some used machines make much noise, then I thought as sound (noise) causes mechanical energy, why not convert that mechanical into electrical energy as microphones do to convert the sound into electrical signals? But here, i would like that device to be more efficient than a microphone.
So if anyone worked on the same project or knows something about it that can be helpful, please let me know.
Thank you.
I will be posting here what I've done so far.

my friend
i m also working on this project.would you help me in all stages from beagining to last step

 

[kthouz]

my friend
i m also working on this project.would you help me in all stages from beginning to last step

Look, am sorry I could not carry out this project since at my school, I could not find all the necessary equipment to implement that machine. That I was advised by a teacher that I had chosen to supervise me. However, I still thinking that the key point is the understanding of piezzo-electric materials. These are types of materials which present potential difference when they undergo a deformation. Just try to find out some books. Furthermore, do not think about amplification (since you would fall in the context of the microphone). I wish I could be more helpful, so fill free to contact me directly if you want at giray03@yahoo.fr
Best wishes my friend.

P.S: Would you also refer to the #8 comment of this thread. Loren Booda has talked about something like "Magnetic Damper" and I think it may be interesting. Please check on it.

I would foremost consider a magnetic damper (e.g., a magnet and a coil mounted on relatively vibrating surfaces) that generates current.

Also, a putative model for a Maxwell's demon, of which there are many applied to "thermal acoustic noise," could more realistically be modified to your purpose.

 

[sophiecentaur]

If you shout into a loudspeaker cone, the electrical energy it will produce can drive a distant earphone. With a jet engine a few metres away, the energy level would be a bit higher than that but you could only intercept a small fraction of what the engine is producing.
This article -
http://www.quiet.org/readings/tatum.htm"
gives you some idea of the flow of sound energy.
60dB, which corresponds to 'normal conversation', corresponds to 1 microWatt per square metre.
120dB is around a nearby Jet engine noise level and would correspond to just 1W per square metre.

Allowing for inefficiency in any transducer you were using, this would probably end up as 0.1W of useful electrical energy. As a way of re-using 'lost' noise energy it seems to be pretty poor value, unfortunately.

It is actually amazing what a very good job your ears do, when you think that 0dB corresponds roughlt to the threshold of hearing. A millionth of a normal conversation level can just be detected.

 

[kwaekins]

I have considered using crystals as a primary source for energy generation. Consider a turning fork. It is not large, nor loud, yet it can shatter glass. I am sure with the primary tone and it's harmonics, some acustic engineering and channeling it's point of critical mass or it's most effective convergent frequency; energy can be gleaned. The problem is not creating energy, the problem is increasing the yield. Once you increase the yeild of one, the same approach can be use to increase all forms of energu.

 

[JaredJames]

I have considered using crystals as a primary source for energy generation. Consider a turning fork. It is not large, nor loud, yet it can shatter glass. I am sure with the primary tone and it's harmonics, some acustic engineering and channeling it's point of critical mass or it's most effective convergent frequency; energy can be gleaned. The problem is not creating energy, the problem is increasing the yield. Once you increase the yeild of one, the same approach can be use to increase all forms of energu.

Increasing the yield?

The energy has to come from somewhere. You can't just take a small amount and output a large amount.

Are you aware why a tuning fork is able to break glass?