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Yet Another Perpetual Motion Device 563

The Star reports on this inventor breaking all the laws of physics as far as free energy goes. It even provoked interest from "esteemed Massachusetts Institute of Technology professor Markus Zahn". I would like to know how this seemingly backyard enthusiast's experimental set up has not been tried a million times over the years. It seems so simple and too good to be true. The article has links to a multi-part video demo of the device accelerating an electric motor under load for free!
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Yet Another Perpetual Motion Hoax

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  • I tried to find an instance (via googling) where his device was left at a lab where scientists spent some time on it but I cannot find such a thing. I would think they would be curious enough to at least try. I think that because his device does the "impossible" than there is no sense looking at it? It probably isn't a perpetual energy thingie but how does it do what it does? Remember when it was impossible for the human body to sit in anything that accelerated as fast as 60mph?
    • by Rei ( 128717 ) on Saturday February 09, 2008 @11:43AM (#22360160) Homepage
      It's really, really simple. He has a spinning magnet and metal bars with coils of wire wrapped around them around the magnet. What happens when it spins? That's right, you induce AC current. What happens when you induce a fluctuating magnetic field through a metal? That's right, hysteresis drag. So, he's basically built a magnetic brake. Then he shorts out his coils, and what happens? Sure enough, it accelerates; he's shorted out his brake!

      Nothing to see here, move along.
      • by LordKaT ( 619540 ) on Saturday February 09, 2008 @11:57AM (#22360294) Homepage Journal
        I don't know what you just said, but it sounds good. Could you tell me how I can short out the brakes on my car?
      • What happens when you induce a fluctuating magnetic field through a metal? That's right, hysteresis drag. So, he's basically built a magnetic brake. Then he shorts out his coils, and what happens? Sure enough, it accelerates; he's shorted out his brake!
        Well, I think he's inducing magnets through a magnetic field--not a metal. And this doesn't act as a break but instead speeds it up. The interesting concept here is that he's using a property known as Lenz's Law [] that creates something called back EMF through those coils of wire that used to have energy running through them. If you watch all four parts, it seems that once the generator reaches a certain speed, it does not slow down when he cuts power to the system. Instead the two coils are still generating electricity from the magnets flying by them due to Lenz's law. Which is then fed into the generator which then spins the magnets which then cause a current in the coils which then ... etc.

        Nothing to see here, move along.
        Although not a physicist, I do not agree with that statement. From what I've seen, from what the MIT scientists have seen, this merits further investigation. I have many questions: Does this scale up? How strong are his magnets? Do the magnets depolarize over time? If he speeds it up really fast, does it pass an equilibrium point and start to accelerate with the feedback energy? Can he produce energy from the closed system and charge a batter?

        Wow, I'm almost cautiously excited. Call me stupid but I want to know more.
        • by rucs_hack ( 784150 ) on Saturday February 09, 2008 @12:32PM (#22360590)
          Perpetual motion I don't know about, but if this device can be kept going for a longer time without too much energy input, then it might have application in transportation.

        • by mikers ( 137971 ) on Saturday February 09, 2008 @12:40PM (#22360664)
          If you watch all four parts, it seems that once the generator reaches a certain speed, it does not slow down when he cuts power to the system. Instead the two coils are still generating electricity from the magnets flying by them

          Actually, he never does cut power to the induction motor. He shorts or re-connects the electromagnet coils (that are part of the generator assembly).

          What he demonstrates is that for the same or less power (Volts*Amps) of input to the motor driving the generator, he can cause the whole assembly to accelerate while using less power.

          That is the interesting part (one more time): He can cause acceleration of the motor, while under a constant load, using less power.

          Not a perpetual machine, but rather a really unusual way to get higher efficiency from a motor-generator assembly.

          My concern is that in one of video parts (three I think), he shows a graph describing what he is doing in his experiments, and he shows a chart that has the constant speed/power line, a decelerating line (disconnected electromagnets) and the exponential acceleration line. He never tests it far enough -- and in the last part (or second last) he shows a plain split-phase induction motor and puts a small set of permanent magnets next to it. Notice that when he puts the small magnets next to the shaft of the motor it accelerates, but he keeps shutting the motor off to "prevent the shaft from getting magnetized". That may be the ultimate problem here, it might just be a short-lived affect from magnets. Once the whole assembly is magnetized, you don't gain any more from this effect.

          • Re: (Score:3, Insightful)

            by fbjon ( 692006 )
            Judging by how the rig bounces about when spinning at high speed, I don't blame him for not pushing his luck. I agree though, as a layman, it looks like he has a more efficient motor.
          • by noidentity ( 188756 ) on Saturday February 09, 2008 @02:49PM (#22361734)

            What he demonstrates is that for the same or less power (Volts*Amps) of input to the motor driving the generator, he can cause the whole assembly to accelerate while using less power.

            I can do the same, by applying a brake for the first case, and not applying it for the second case. Now, if he shows that the first case's efficiency is close to 100% (with the brake), then we've got something noteworthy.

          • Re: (Score:3, Informative)

            by cluckshot ( 658931 )

            Using a standard stepper motor which is essentially what he has here, the stepper motor can be timed to hit the Back EMF pulse in a position where it becomes a propulsion pulse. Typically the Back EMF pulse is proportional to the load on the motor. The result is that a forward kick equal to the RMS of the Back EMF pulse can be achieved. Since the motor rotated with force equal to the induced coil current less some losses like friction etc, the motor without the Back EMF pulse would be almost 100% effic

        • by wdhowellsr ( 530924 ) on Saturday February 09, 2008 @01:12PM (#22360994)
          I build residential, commercial and industrial power factor correction devices. I've seen some large water treatment plant motors operating at below 50% efficiency. Before we start blowing money on free energy we should look at how much is wasted right now. As a test I went to a local applicance store and tested five identical EnergyStar refrigerators for the efficiency of the compressor motor. Every one of them was less than 95% efficient because motors must be sized larger than the actual load to account for loss over time. I had one Subway restaurant save about forty percent on their monthly electric bill due to increase in inductive energy efficiency. For whatever reason we can't seem to see the forest through the trees.
          • by JustOK ( 667959 ) on Saturday February 09, 2008 @01:33PM (#22361156) Journal
            I can see the forest perfectly, thank you. I cut down the trees and put in a parking lot.
          • by Anne Thwacks ( 531696 ) on Saturday February 09, 2008 @05:07PM (#22362890)
            I worked for four years or more in a company that made thyristor based control gear that reduced the voltage to just the amount needed to keep the motor running. It was capable of reacting fast enough to load changes to work on the presses that stamp out Ford bumpers.

            The company went bust because, although client companies who bought it saved up to 30% of their power, most did not want to know.

            "We dont care about energy saving - it might break down, and then we would lose production."

            It was not unreliable: It was used to mill the corn for a well known cornflake manufacturer ;->

            There is a major problem getting people to buy energy saving in industry.

            Its not much better in the domestic area. I later worked on domestic energy saving equipment which, here in the UK could alone save enough energy to meet the Kyoto treaty requirements. I got it working but the backers pulled out after a government backed Quango said "Ohms law does not apply in the UK"

        • Are not that it's a "perpetual motion machine" but that he may have found a way to make electric motors significantly more efficient. This by itself is an entirely believable claim, and I think worthy of further serious investigation.
      • typical slashdot (Score:5, Interesting)

        by Great_Geek ( 237841 ) on Saturday February 09, 2008 @12:21PM (#22360492)
        Let's see, shows Markus Zahn wrote a book "Electromagnetic Field Theory: A Problem Solving Approach" in 1979 (the first item in many publications); he is a professor at MIT - part of the Lab of Electromagnets and Electronic Systems. Gee, I wonder if he understands motors and magnetic brakes.

        Clearly the professors (Markus Zahn and at least one other) have studied the invention and cannot explain the result. You, on the other hand, based on cursory information, understand every little detail. So typically slashdot: I took a course in university on the subject, so my opinion is better than the professors.

        • by imsabbel ( 611519 ) on Saturday February 09, 2008 @02:12PM (#22361468)
          The way i understand those kind of claims, they showed him the thing for 10 minutes, and pressured him "Explain Exactly How This Works!".

          If he gives an evading answer, like "i cannot say anything from this, i need to examin it closer", the wonders of press will make a "Professor cannot explain what happens!!!1" out of it.
        • by mangu ( 126918 ) on Saturday February 09, 2008 @02:16PM (#22361492)

          Clearly the professors (Markus Zahn and at least one other) have studied the invention and cannot explain the result. You, on the other hand, based on cursory information, understand every little detail

          I'd be willing to bet that if you asked the professors off the record they would give you an explanation in the line of what the GP did, but they have to be more restrained in their public declarations. They are careful not to make public guesses about how it works, because, inevitably, they would be wrong about some small detail and the "inventor" would be able to say the scientists know nothing.

          Or do you think scientists are so stupid that, after more than a hundred years of research, they would have overlooked a basic principle that a dyslexic cook can discover by himself? The scientists have not studied the invention at all, the only reason why they cannot explain the result is because they have insufficient information. It's not as if this guy had published the plans for his machine, all the professors could see was a demo presented by the inventor.

          This guy seems to be crook who tries to do his job by letting the victims read between the lines. He has *wink, wink* NOT invented a perpetual motion engine, and he is *wink, wink* NOT after investments for "further development".

          • Re: (Score:3, Insightful)

            Or do you think scientists are so stupid that, after more than a hundred years of research, they would have overlooked a basic principle that a dyslexic cook can discover by himself?

            Umm... We need to be careful about that. We owe some pretty important physics to a dyslexic patent clerk. But, it's important to remember that a scientist is still a normal person. In the situation of a demonstration, they are just as easily deceived as a normal person - sometimes even more easily. Perpetual motion is an extraordinary claim, and requires extraordinary proof. In all cases it must be approached with great care and deliberation to avoid error.

          • by Great_Geek ( 237841 ) on Saturday February 09, 2008 @04:40PM (#22362652)
            A much more informative article is at []

            Some quotes:
              "they have demonstrated the Perepiteia to a number of labs and universities across North America, including the University of Virginia, Michigan State University, the University of Toronto and Queens University."

              Prof. Habash of University of Ottawa looked at it: "It accelerates, but when it comes to an explanation, there is no backing theory for it. That's why we're consulting MIT. But at this time we can't support any claim."

              Prof. Zahn of MIT: "It's an unusual phenomena I wouldn't have predicted in advance. But I saw it. It's real. Now I'm just trying to figure it out."

            What I infer from this is that competent people have looked at it in some detail and were surprised, so it is possible that a new more efficient motor has been invented (it is also possible that some old forgotten motor is now more efficient because of new material, or any of a million possible outcomes.)

            It is even possible that the professors forgot about magnetic brakes and other basic undergrad stuff; but I would not bet on that. It is also possible that this is a "con" but I also would not bet on that.

            Some people seem very sure that this is non-sense. Would any of them like to give me 10-to-1 odds? That is, if turns out to be non-sense, I lose $1; it it turns out to be a more efficient motor, I win $10. (I will ignore the vanishingly small probability that it actually is revolutionary.) This means I am offering free money to people who are 100% sure. Even if you are only 95% sure, you still have positive expected value. On second thought, I have no desire to be jailed by some over-zealous police or DA when I am flying somewhere; so the bet will be for bragging rights only - no money.
      • by JMandingo ( 325160 ) on Saturday February 09, 2008 @12:45PM (#22360716)
        Agreed. What happens when he removes the coils from the system entirely? Does the motor spin slower or faster than the test with the back EMF? That question is so obvious that I would have expected it to be addressed at the very start of his video.
      • The effects (Score:5, Interesting)

        by Anonymous Coward on Saturday February 09, 2008 @01:34PM (#22361168)
        This has been done before and experimented with. Plenty of kids have tried this in their science classes in grade school and junior high. I know I did. Plenty of teachers have failed the students for doing this because, "Perpetual Motion is Impossible, you cannot explain whaty ou have done, you have learned nothing." I know mine did. [note, yes, bitter]

        Skipping past the bitterness.

        What is occurring here actually does make sense. There are several arrangements that can be used to make it occur. So far the pattern I have seen is the mere circle with an outlying magnet. Another option is made up of 15 magnets spaced inside the wheel instead of outside of it. They accelerate the outer wheel rapidly - much quicker - and make the entire unit easier to suspend within a vacuum between two plates. You can then place a coil outside the vacuum encased box, that is passive and generates electricity through the changing interior fields. The inner system is started by placing a single magnet briefly on the outside to start movement - after which the interior cascades out of its initial stability. The other magnets prevent it from finding stability again and the system accelerates until it instead reaches the next state of field stability at a set rotational speed.

        A fun side effect is that the system also operates as a gyroscopic platter.

        But, what happens after significant time? In the exterior-to-wheel scenarios the magnetic field eventually stabilizes. Outside of a vacuum it generally fails to stabilize because of minimal drag forces that cause it to essentially overheat and stop. This is a case of mechanical fault. Mechanical fault does not bar it from being "perpetual motion", but does reduce the long term functionality.

        However. What happens with the interior-to-wheel scenarios? They also stabilize. However they stabilize within a rotating field. The EM field actually slows - but does not stop - and continues to rotate around the exterior generating energy through the coil.


        So why is this not perpetual energy and where is this energy coming from?

        Magnets. It is a straight forward answer. It takes a lot of energy to polarize a magnetic material. Rather, to magnetize it. Magnetic materials over long use lose their polarization. Ultimately they neutralize or become very weak.

        When you create a system like this the magnets are under constant force. After enough time one or more magnets depolarize and the system returns to static stability. However, because of the nature of magnets, this can take a significant amount of time.

        Magnets store a lot of energy in an alternative form. They, rather efficiently, release that energy. Unfortunately, they do obey the basic laws of thermodynamics. Thus, less energy comes out of them than what went in.

        You can think of a magnet like a funky capacitor. You can put a lot into it and you will get most of that back out, but you will not get all of it.


        So, what is the use of these systems? Stored energy. The problem is that magnets with sufficiently strong fields are not cheap and do not come readily. We could produce them, but we would be returned to the same problem of where do we get the original energy from to "charge"/magnetize the magnets.

        How could we use this stored energy? Well, using the gyroscopic nature of the spinning platters, one option would be to place them within vehicles and use them for electrical charge to power the vehicle. Of course, you would have to shield the EM field to keep from having two cars snap together like a couple of magnets ;). But, the gyroscope would reduce the chances of a car tipping or flipping and the platter would keep it going for quite some time. It could run and charge batteries when the car is idle and it could add energy to the system while it is going. But, eventually, the magnets would wear out. The car would then have to "refill" by making it to a station before the batterie
    • Remember when it was impossible for the human body to sit in anything that accelerated as fast as 60mph?
      MPH is Miles / Hour == d/t == Velocity. Not acceleration. Acceleration is d/(t^2)
      • by jcorno ( 889560 )

        Remember when it was impossible for the human body to sit in anything that accelerated as fast as 60mph?
        MPH is Miles / Hour == d/t == Velocity. Not acceleration. Acceleration is d/(t^2)

        If we're being pedantic, it's a speed, not a velocity. Velocity is a vector, speed + direction.
  • Casimer Effect (Score:4, Insightful)

    by Anonymous Coward on Saturday February 09, 2008 @11:30AM (#22360048)
    The problem is the magnetic field degrades.
  • by tkrotchko ( 124118 ) * on Saturday February 09, 2008 @11:30AM (#22360050) Homepage
    The people involved are going out of their way to say it's not perpetual motion; rather, the experiment is not working as predicted. There are many explanations for that. The guy involved has basically wrecked his life over tinkering with it.

    And the articles don't give enough details to judge much.

    But so far, slashdot is the only article that talks about perpetual motion.
    • Re: (Score:2, Troll)

      by knewter ( 62953 )
      WTF is wrong with you? The linked article is has perpetual motion in its *title*. What idiot modded this crap informative?
  • Contrast (Score:4, Funny)

    by QuickFox ( 311231 ) on Saturday February 09, 2008 @11:33AM (#22360076)
    Yet another Perpetual Motion Device, brought to you by Slashdot, the perfect Perpetual Immobility Device.
  • by Anonymous Coward on Saturday February 09, 2008 @11:34AM (#22360078)
    Connect the corpse of Beethoven up to a generator. Generator provides electricity for CD-player. CD-Player plays Britney Spears songs over and over. Beethoven spins in his grave providing mechanical energy to generator.
  • by A Friendly Troll ( 1017492 ) on Saturday February 09, 2008 @11:34AM (#22360088)

    There's no talk of perpetual motion. No whisper of broken scientific laws or free energy. Zahn would never go there - at least not yet. But he does see the potential for making electric motors more efficient, and this itself is no small feat.

    Why the headline, Taco?
    • by pla ( 258480 ) on Saturday February 09, 2008 @11:45AM (#22360178) Journal
      Why the headline, Taco?

      In the very first paragraph, TFA states "he'll demonstrate an invention that appears - though he doesn't dare say it - to operate as a perpetual motion machine."

      As for why "nobody's calling it" that, TFA answers that as well, with:

      It's for this reason the 46-year-old inventor has learned to walk on thin ice when dealing with academics and engineers, who he must win over to be taken seriously. Credibility, after all, can't be invented. It must be earned. "I have to be humble. If you say the wrong thing at the wrong time, you can lose support."

      Seems straightforward enough. The guy believes (or wants others to believe) that he has made a perpetual motion machine, but calling it as much would result in his instant damning to the land of crackpots. So instead of claiming something widely considered impossible, he describes it as simply some sort of "very efficient" electric motor, a perfectly reasonable (if unlikely, given his background) idea.
      • by CustomDesigned ( 250089 ) <> on Saturday February 09, 2008 @12:06PM (#22360370) Homepage Journal
        I knew about a guy who had invented a "zero bandwidth transmitter" 40 years ago. When I saw it 20 years ago, he was very bitter that no one would even look at his invention. He could demonstrate voice communication over miles, with official FCC interference monitoring equipment showing "zero bandwidth". A friend of his showed me the basics of how it worked. It was actually a "spread spectrum" transmitter. He actually had a useful invention (same principle invented since by others). But he insisted on calling it "zero bandwidth", and mocked the experts who explained the mathematical impossibility of such a thing - because he had working prototypes, the experts were clearly deluded in his mind.
        • by ChromaticDragon ( 1034458 ) on Saturday February 09, 2008 @12:24PM (#22360522)
          Not to knock the possible independent invention of Spread Spectrum techniques by your friend...

          Not to dismiss your remarks regarding that others may have also independently invented this sometime in the last 40 years (though I believe you're simply referring to civilian commercial use in the past few decades)...

          But it would seem to take just a wee bit of effort of web research to demonstrate that various forms of this have been around a lot longer.

          Goodness. Tesla patented a form of frequency hopping in 1900!!

          Hedy Lamer is famous for being the woman who more or less invented and patented an early form of CDMA in 1940.

          Granted, these things didn't have widespread civilian use and applications until the last few decades. But it seems strange to present your story the way you did. It would seem likely depending in his implementation that this chap couldn't have patented it in any case due to longstanding prior patents.

          Furthermore, describing this as "zero bandwidth" really seems strange. I can certainly understand why engineers would have dismissed this. A more accurate description of spread spectrum would be "infinite bandwidth". That is why it's called SPREAD spectrum. It flattens out the wave in the frequency domain. Simply because the power in any given range drops to the noise floor isn't quite the same as it truly being zero bandwidth.

        • Without seeing diagrams and all, it's very hard for me to guess what is going on. It's entirely possible that it's not really a novel phenomenon, just a novel setup. We've had things like that happen before in the labs; its explainable with current physics, just too complicated to explain within the same day you discover it. I suspect you are correct in that this machine is not perpetual motion, but could very well be an interesting device for other purposes. I'm actually curious to see it work!

          The text of
      • I have devices branded "Green Plug" for our refrigerator and washing machine. These devices modulate the AC waveform fed to the motor. The result is quieter operation, and measurably less power used. It works because the magnetic fields in the motor store energy, causing the power draw to vary over each cycle. The device feeds only the power needed. Without the device, the excess power is dissipated as noise and heat. These devices are no longer sold, because large motors now typically incorporate th
  • by Spy der Mann ( 805235 ) <spydermann.slashdot@ g m> on Saturday February 09, 2008 @11:37AM (#22360106) Homepage Journal
    From another source []:

    In Heins' machine, he explains that magnetic friction somehow gets turned into a magnetic boost. Working with an electric motor, he attached the drive shaft to a steel rotor with small round magnets lining its outer edges. In this set-up of a simple generator, the rotor would spin so that the magnets passed by a wire coil just in front of them, generating electrical energy.

    Then Heins did an experiment: he overloaded the generator to get a current, which typically causes the wire coil to build up a large electromagnetic field. Usually, this kind of electromagnetic field creates an effect called "Back EMF" due to the so-called Lenz's law. The effect should repel the spinning magnets on the rotor, and slow them down until the motor stops completely, in accordance with the law of conservation.

    But instead of stopping, the rotor began to accelerate. Heins recounts that the first time it happened, the magnets starting flying off and hitting the walls, as he ducked for cover.

    The magnetic friction wasn't repelling the magnets and wire coil. Instead, as Heins explains, the steel rotor and driveshaft had conducted the magnetic resistance away from the coil and back into the electric motor. In effect, the Back EMF was boosting the magnetic fields used by the motor to generate electrical energy and cause acceleration.

    He also says it's *NOT* a perpetual motion machine. He's asking experts to explain him why that happened, and if it could turn into a way to make electrical generators more efficient.
    • by Warbothong ( 905464 ) on Saturday February 09, 2008 @12:11PM (#22360410) Homepage
      It seems that his setup is using 'permanent' magnets to accelerate a motor instead of slow it down. What this would say to me is that the retardation effects are being shifted from the motor to the magnets. This would comply with current Physical knowledge, since 'permanent' magnets are not truly permanent, only in the sense that they can't be turned on and off like electromagnets.

      If this is the case then expect the 'permanent' magnets to lose their magnetism over time, and if this magnetism was imparted to them from an industrial process (ie. they are not naturally magnetic) then the extra energy would be coming from the magnet factory's machinery.

      It is still interesting, however, since such a method would be a way of storing energy, reducing the need for batteries. To be useful this technique would need to be measured in terms of extra energy imparted, magnet lifetime and whether the weight of the magnets would be better used to hold more batteries.

      IAAPBIDHMTGO (I Am A Physicist But I Don't Have Much To Go On)
    • Re: (Score:3, Interesting)

      But instead of stopping, the rotor began to accelerate. Heins recounts that the first time it happened, the magnets starting flying off and hitting the walls, as he ducked for cover.

      So from all I could gather he's claiming this thing produces a net output (yeah he won't state it that way, but I don't see what else he could be saying). It sounds like he's saying there's a large amount of energy coming from somewhere in a short period of time; i.e., this is not some wimpy effect only measurable with careful

  • I really wish that, instead of running "person claims they can do the impossible" stories, newspapers would run exciting stories explaining the basics of thermodynamics, what energy is, and nuclear physics and the background behind Boyle's gas law.

    These days, we're wondering when the oil's going to run out, and we need to look to how we get the most energy out of our Sun and gravity - the only real sources of energy on this planet, all other sources being derivatives.

    Why can't we have a more intelligent pub
  • electric motors rely on rotating magnetic fields. if you have permanent magnets attached to any supposed "perpetual motion" device, there will be a source of rotating magnetic fields somewhere which require power (and yes, this makes any such thing a hoax).

    Energy in == energy out with no known exceptions.
    • Re: (Score:3, Interesting)

      (and yes, this makes any such thing a hoax).

      That's a little too harsh. There is always the remote change that one of these perpetual motion inventors stumbles across a new source of previously unusable energy.

      That's doesn't make it a "perpetual motion" machine, but it could still be enormously useful.

      Off the top of my head, I could imagine that the earth's magnetic field might be used as an energy source. Some unknown affect might convert subatomic particles to energy in special situations.

      The bottom line i

    • Energy in == energy out with no known exceptions.

      Total energy, yes, but all machines whose purpose is anything other than producing heat waste some. For non-heaters, energy in energy out.

  • 2nd law. (Score:5, Insightful)

    by headkase ( 533448 ) on Saturday February 09, 2008 @11:49AM (#22360218)
    Thermodynamics just says you can't win when you're talking about the whole Universe. Once you start to get into smaller sections of it you can increase organization locally but it is always at the expense of more global energies. Life here on Earth is an example of this - we're more organized but the Sun pumps out a lot of wasted energy to feed that organization. It's entirely possible that some kind of machine could be built to extract energy locally which ultimately has a global source but that does not mean its perpetual, the Universe will still wind down total energy wise in the global space.
    • by neomunk ( 913773 )
      Thank you.

      I've tried to explain exactly that to a few people, but the addition of your Sun/Earth model makes your explanation crisp and concise.
  • Videos (Score:4, Informative)

    by chihowa ( 366380 ) on Saturday February 09, 2008 @11:55AM (#22360274)
    He has a series of Youtube videos [] where he shows it off and attempts to explain it.
  • by marvinglenn ( 195135 ) on Saturday February 09, 2008 @11:57AM (#22360290)

    It's now Jan. 28 - D Day. Heins has modified his test so the effects observed are difficult to deny. He holds a permanent magnet a few centimetres away from the driveshaft of an electric motor, and the magnetic field it creates causes the motor to accelerate. [...]

    I will assume that the motor is a common DC motor with field on the stator, armature on the rotor. If the flux from the magnet he's holding near the shaft is canceling some of the flux from the field, then the motor will naturally speed up. The opposite effect is when you increase the flux from the field... the motor slows down.
  • ...clearly the remaining component which he needs to make it complete is a flux capacitor (and perhaps a deLorean).
  • It's hard to tell exactly what's going on-- the first thing I'm wondering about is whether he's collecting stray fields (the modern world is full of electromagnetic fields)-- but I am, in fact, impressed with the fact that he's actually going to MIT and showing it to people asking for an opinion from people who have a good understanding of science. That's the right step; good move.
  • by Animats ( 122034 ) on Saturday February 09, 2008 @01:25PM (#22361090) Homepage

    After watching the videos (whew!) here's what seems to be happening.

    The setup is an induction motor driving a magnetic brake. The brake has both permanent magnets and coils. With the coils unloaded, there's some braking effect, as you can see when he turns the magnet wheel by hand. With the coils shorted, the braking effect decreases. This seems backwards, because, usually, shorting a generator increases the mechanical load. That's why this guy thinks he has something.

    There's a classic Physics 101 demo where you have a big conductive disk rotating between the poles of an electromagnet, and when you short the electromagnet, there's a huge drag on the disk and it stops. That's an eddy current brake, and it's the analogy this guy is depending on.

    But, in fact, he's re-invented a known type of magnetic brake. This isn't an eddy current brake; the addition of permanent magnets makes it something else. A known something else.

    Here's an example of such a permanent magnet brake []. Note that "the brake is applied when the coil current is zero", just as with the "Perepiteia" device. This is backwards from most magnetic brakes. Here, the permanent magnets are providing the field for braking, and current in the coil overrides the permanent magnets. In the "Perepiteia" device, the coils act as generators and have current through them the magnet wheel is rotating and the coils are shorted. This effect requires a nonlinear magnetic steel, so this is non-trivial magnetically. But commercial electromagnetic simulation software can simulate this effect, so it's well understood physics. It's a rare enough technology that there's no accepted name for this type of brake.

    Note that in the Perepiteia videos, he has to hand-start his wheel, even though it's being driven by an induction motor. That's because, with his setup, the brake drag is at max when the wheel is stationary. With the wheel stationary, there's no current in the coils, so there's nothing to override the permanent magnets. Once the wheel is turning, the coils generate some power and reduce the braking effect.

    There's even a patent on the application of this principle to powered window blinds. See U.S. Patent #6,967,418. There, it's used to hold the blinds in place with power off.

    • by NixieBunny ( 859050 ) on Saturday February 09, 2008 @02:02PM (#22361400) Homepage

      I think you're missing an important part of the puzzle.

      When I watched the video, I was struck by how the coil on the right doesn't have a pole piece on its far end to take the magnetic flux back to the permanent magnet wheel. Then I saw him demonstrate the difference between having a brass motor shaft and a steel shaft, and I had an inkling of what was going on.

      An induction motor is a very complex device whose complexity is masked by its physical simplicity. The induction motor builds a rotating magnetic field in the rotor by inducing current flow into the aluminum rotor windings from the AC stator coil (as any power transformer does). The interaction between the induced field and the stator field causes the motor to turn. The rotor has specific requirements with regard to the shape of the windings to achieve maximum efficiency. Understanding the current flow and the magnetic flux is a job for theoretical experts (which I'm not).

      Notice that the apparatus is mounted on a steel table. This provides a flux path from the motor housing to the black coil at the right end of the machine. The addition of his steel shaft has "completed the magnetic circuit" between this coil (an AC generator) and the induction motor rotor, which will do very interesting things to the magnetic field on the rotor! Especially since the field he generates is an AC field with what, 16 poles? I think he has a four pole 1750 RPM induction motor.

  • by Ecuador ( 740021 ) on Saturday February 09, 2008 @03:03PM (#22361844) Homepage
    He doesn't only get his physics wrong, but he even named the device erroneously. There is no greek word "perepiteia" (it might sound greek to you, but it sounds just silly to Greeks), instead he wanted to say "peripeteia" ( It could be his "mild dyslexia" at work, however he uses the "dyslexia" excuse for his bad performance in math - although all the dyslectics I have known don't have a problem with math (feel free to enlighten me on this, it is just my personal experience). Anyway, I just think it boils down to him not doing his "homework"... Personally, I wouldn't invest on his startup...
  • by Antique Geekmeister ( 740220 ) on Saturday February 09, 2008 @09:57PM (#22365540)
    I don't want an MIT physics professor, except as a consultant. I want James Randi, the stage magicion who's now debunking psychic frauds, to look at the apparatus and make sure there's nothing strange going on.

    For example, most voltage and current meters do no measurement of phase delay between the curent and the voltage. A bit of odd impedance in a motor can often affect its performance considerably by drawing more of the current when it's at the highest voltage and the maximum power is delivered to it, rather than wasting energy in conductive losses at low voltages. And oddball impedances can cause surprising loads to the sources of electrical power, which are not noticed unless you look carefully at the fuel consumption for the upstream generator or examine the electrical load with better instruments. The relevant phrase to look this up is "power factor correction".
  • by Kent Recal ( 714863 ) on Sunday February 10, 2008 @12:28AM (#22366586)
    Verbatim quote from the article:

    There's no talk of perpetual motion. No whisper of broken scientific laws or free energy. Zahn would never go there - at least not yet. But he does see the potential for making electric motors more efficient, and this itself is no small feat.

    So how do we get from that statement to the slashdot headline?
    Too much crack? Had a bad month in ad revenue?
  • by sterlingda ( 732011 ) on Sunday February 10, 2008 @01:14AM (#22366902) Homepage Journal
    We posted a feature page about this here: []

    The following are a couple of the better comments we received.

    No Useful Output
    On Feb. 6, 2008, Peter Lindemann, DSc, writes:

    I have reviewed all seven video links. In all fairness, I would like to say that Thane has built some nice demonstrations and spent a lot of time running experiments. That said, the films show nothing important. First of all, the films do not show enough detailed information to evaluate the demonstrations. Second, no free energy is shown. In fact, the generators are never shown producing any useful outputs. They are either shown producing voltage in "open circuit" mode, or they are shown in "short circuit" mode, where the generated voltage drops below one volt. So, ZERO WATTS are produced in either case.

    The changes in mechanical drag are due to changes in inductance and hysteresis. Back in the 1980's, both John Bedini and I independently worked with "variable reluctance" generators. We both saw that these designs work like an inverse to a standard induction generator. That is, they produce maximum drag in "open circuit" mode, and minimum drag in "short circuit" mode. John found that the point of maximum benefit in this situation is to charge a battery, where the impedance of the generator "sees" the battery as a "near short circuit". Under these circumstances, the generator free-wheels and the battery charges quickly.

    Unfortunately, Thane is not showing any useful benefits from the generator output. So, there is no "efficiency" to calculate because there is no output!

    The real problem with these demonstrations has to do with his motor drive. The motor driving his system is a single phase induction motor. This type of motor has almost zero starting torque, and only produces its rated power at rated speed. So, the rated speed of his motor is probably in the neighborhood of 1725 RPM. Running this motor in the 100 RPM range converts 98% of the input electric power to HEAT. He says he has a capacitor in the input circuit to the motor, but this is never shown in schematic, so we don't know how it is hooked up. If the capacitor is connected in SERIES with the motor winding, it will act as a current limiter, and skew the power factor of the motor towards reactive power. This is fine, IF you want to limit the mechanical power of the motor as well. If the capacitor is connected in PARALLEL with the motor winding, it will act to produce reactive power for the motor locally, and reduce the amount of power it draws from the wall. But again, this would only be significant at rated speed.

    The effect he shows when a magnetic field is applied to the motor shaft would be undetectable if he was operating the motor correctly. It is a very weak effect. It is probably caused by the external magnetic field interfering with the induced magnetic field of the rotor. This would not happen if the motor coils were not being severely current limited and the rotor was not "slipping" severely in the rotating magnetic field of the stator.

    My GUESS is that the capacitor is in SERIES with the motor winding. This will limit the current to the motor to a specific maximum. At the speeds he is running these motors, the only other mechanism to hold back the input current would be the resistance of the wire in the motor coils. If that is all he had, the motor would quickly over-heat and melt the insulation right off the wire. The fact that the motor is running hot is proved in the seventh film where a large black fan is shown blowing on the motor!

    From the data presented, my best estimate of the efficiency of the demonstrations is that over 90% of the energy going into the motor is converted to heat. The changes in drag of the generators is standard behavior for variable reluctance topologies

If I had only known, I would have been a locksmith. -- Albert Einstein