Author Topic: Earth Engine permanent magnet power generator  (Read 7542 times)

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Offline daqq

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Re: Earth Engine permanent magnet power generator
« Reply #25 on: September 21, 2019, 06:21:00 pm »
Futureman: Those look great! They should get them independently by some serious organization, such as the UL, TUV, or even send one device to Dave here, to validate their claims.
Believe it or not, pointy haired people do exist!
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Online james_s

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Re: Earth Engine permanent magnet power generator
« Reply #26 on: September 21, 2019, 06:23:14 pm »
Futureman: Those look great! They should get them independently by some serious organization, such as the UL, TUV, or even send one device to Dave here, to validate their claims.

They won't, they know Dave (or any similarly competent engineer) would rip their claims to shreds and point out all the holes in their ideas.
 

Online maginnovision

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Re: Earth Engine permanent magnet power generator
« Reply #27 on: September 21, 2019, 06:25:47 pm »
Futureman: Those look great! They should get them independently by some serious organization, such as the UL, TUV, or even send one device to Dave here, to validate their claims.

They won't, they know Dave (or any similarly competent engineer) would rip their claims to shreds and point out all the holes in their ideas.

Heresy! These aren't just ideas anymore they're real things! He saw them and knows they're real. No need to check them out now just buy them.
 

Offline T3sl4co1l

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Re: Earth Engine permanent magnet power generator
« Reply #28 on: September 22, 2019, 03:02:00 am »
There's no energy "stored" in magnets, magnetism is not energy

The energy density of a field is:
\[ e = \frac{B^2}{2 \mu_0} \]

Integrate over space to get the energy stored in the magnet. :)

Another way to put it: the magnet has a large hysteresis loop in its B-H curve; the area of this curve corresponds to the energy dissipated in going around said loop.  If you used it as a transformer core, that would be its core loss every cycle.

I think it's going to be a "what happens when you short a charged capacitor into a discharged capacitor" situation, i.e., half the energy goes into actual heat, the other half goes into energy in the field.  The magnetic version of charge is flux, which is conserved, but the energy is divided.

The funny thing is, perpetual motion types most likely aren't clever enough to figure out how to extract incremental energy from a magnet.  I'm not even quite sure how you would do that; doing it passively would be difficult (demagnetizing it with an electromagnet will only consume more power), maybe you'd resort to heating it above Curie temp, demagnetizing a bit at a time.

But you need to be careful that you aren't using it as a boring old heat engine -- there is a strong tempco and some recoverable magnetization as long as T < Tc, and this variation could be used to repeatedly convert change in temperature into change in flux density.

Tim
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Offline DTJ

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Re: Earth Engine permanent magnet power generator
« Reply #29 on: September 22, 2019, 03:18:17 am »

There's no energy "stored" in magnets, magnetism is not energy, it just enables the transfer and conversion of energy.


I thought rare earth magnets were manufactured by placing the 'rare earth mix' in strong magnetic field and then the powder is pressed and heated/cooled to 'store' the magnetic field.

I may  be wrong but ff this is correct then energy is stored - or converted because you don't get nothing for nothing. I agree magnetism is not energy a magnet needs to perform work in order for energy to be expended. 

 

Offline imo

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Re: Earth Engine permanent magnet power generator
« Reply #30 on: September 22, 2019, 04:58:57 am »
Magnetic energy density of an neodymium based magnet is around 400000 J/m3 (wikipedia).
 
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Offline IanB

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Re: Earth Engine permanent magnet power generator
« Reply #31 on: September 22, 2019, 05:24:19 am »
There's no energy "stored" in magnets...

In addition to the previous answers, consider that in order to magnetize something you have to rearrange the internal magnetic domains so they are all aligned in the same direction. It takes a certain amount of work to perform this realignment as the domains are reluctant to move and you have to put some energy in to the system to achieve it. Similarly, if a permanent magnet stays magnetized it is internally holding on to the energy used to magnetize it.

That said, the stored energy is not a practical source of power since there is no easy way to get it back.
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Offline ebastler

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Re: Earth Engine permanent magnet power generator
« Reply #32 on: September 22, 2019, 05:49:46 am »
Magnetic energy density of an neodymium based magnet is around 400 000 J/m3 (wikipedia).

That's not a lot. Heating oil has 4E10 J/m³, i.e. a factor of 100 000 more, if I got my math right.

So even if one could design a device which "extracts" that energy from the magnets, things wouldn't look so hot for the "10 kW" or "25 kW" devices mentioned in the posts above...
« Last Edit: September 22, 2019, 06:34:55 am by ebastler »
 

Offline T3sl4co1l

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Re: Earth Engine permanent magnet power generator
« Reply #33 on: September 22, 2019, 06:14:38 am »
Indeed.  And really, we're just arguing about facially false statements, without escaping from the already false premises these people use.  The only real solution is to simply point and laugh.  Don't comment, don't share.  Gently remind others that, yes, it is as dumb and antiscientific and too-good-to-be as it sounds.  That's it.  Actually trying to enter into an argument based upon a false premise is more disingenuous to yourself, than the premise is to others.

Tim
Seven Transistor Labs, LLC
Electronic design, from concept to prototype.
Bringing a project to life?  Send me a message!
 

Offline imo

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Re: Earth Engine permanent magnet power generator
« Reply #34 on: September 22, 2019, 04:38:06 pm »
Magnetic energy density of an neodymium based magnet is around 400 000 J/m3 (wikipedia).

That's not a lot. Heating oil has 4E10 J/m³, i.e. a factor of 100 000 more, if I got my math right.

So even if one could design a device which "extracts" that energy from the magnets, things wouldn't look so hot for the "10 kW" or "25 kW" devices mentioned in the posts above...

Unless they bought a piece of "magnetar" off ebay, with the magnetic energy density of 40 000 000 000 000 000 000 000 000 J/m3 .. :)
 


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