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Electron / muon

  1. Apr 23, 2006 #1

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    I was actually pondering the existence of modern electronics, and the ability of a magnetic generator which applies a force to move electrons in a copper wire. As another energy source is used to turn the turbine (e.g coal, fuel - combustion, nuclear), the magnets apply a electromagnetic force against the electrons in the coil, and so too in the wire connected to the generator. Thus the power source alternates (i.e it move either way, the poles are changing - A.C) and the electrons are slammed across the resistors connected to the wire, applying energy to them.

    I was thinking would there be any other ways in which we could use particles like the electron to supply energy to devices? Maybe even slightly modifying the key fundamentals so that we could dramatically increase the energy output (yeild) ?

    I was considering the existence of a muon (i.e the heavy electron, ~207 greater in mass then the electron). What if we replaced this with the electron? Obviously there are major problems, - the first that the muon apparently has a finite life-time. Also they would probably be too unstable in a simple metal wire - they would probably not act the same as an electron, so material engineering would need to be considered to encase such a particle. - Still its intresting to think about such possibilities? Does anybody have any thoughts on this subject?
     
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  3. Apr 23, 2006 #2

    Astronuc

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    I think you meant to write, what if we replace the electron with the muon.

    Well, as was mentioned, the muon has a short life-time, ~2.2 microseconds, so by that alone using muons for any energy source is impractical. Secondly, if the muon could replace an electron, it is much heavy, which means its response to a given electric field is considerable different - it moves more slowly.

    I doubt that we will be changing the 'key fundamentals' in order to make energy generation more efficient.
     
  4. Apr 24, 2006 #3

    Morbius

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    Astronuc,

    I concur. Besides the inefficiencies in our methods of generating electricity are not
    in the generator. The generator is actually a very efficient devices.

    No - practically all the inefficiency is in the steam cycle - and the problems there have
    to do with the 2nd Law of Thermodynamics - one can't "get around" the laws of physics.

    Dr. Gregory Greenman
    Physicist
     
  5. Apr 25, 2006 #4

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    Well I agree based on the fact (which I too mentioned initially), that simply due to the relatively short half life of the muon this is a impracticle idea (amongst other things). However, because we simply limit ourselves to using electronics as the means to transfer energy, we must also realise that this will have serious consequences on the future of technology - largly due to these physical limitations. As engineering systems become more complex, larger and more sophisticated, eventually we will see drawbacks which limit us seriously due to the lack of power available, this is already a very real fact with 'chemical source' space propulsion.
     
  6. Apr 26, 2006 #5
    Perhaps this discussion is a little over my head, but it is not true that electrons, given their size, have the highest charge density? How is that a limitation?

    Are you talking about something like light to transfer energy, the same as fiber optics are being used for information transfer?
     
    Last edited: Apr 26, 2006
  7. Apr 26, 2006 #6
    To echo Candyman, I don't see a definite limitation there. The biggest problem I see with power transmission is the loss of energy in the form of heat due to resistance in the wire. Potentially, we can (nearly) eliminate that problem through the use of super-conducting materials, so high temperature super-conductors are an active area of research. If that happens, we'll be able to get the same amount of energy at the end of the wire as was originally transmitted, using electrons. You can't ask for anything better.
     
  8. Apr 26, 2006 #7

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    As we try to maximize the efficiency of energy production systems such as fossil, nuclear ect. the physical limitations that we are dealing with are initially due to the in-efficiency of the respective system (in large part due to the conversion rates of one form of energy into the other - into the usuable electrical energy which runs appliances).

    However systems will increase to their maximum physically limited efficiency and then ultimately the limitiations will lie in the electrical transfer system (electrons transferring their energy to an appliance). Note: I am not talking about undersirable resistance - energy loss as heat. To a certain point, the generator will only be able to turn so fast, the density of the electric current can only physically be so much and the needs of more power for more sophisticated and complex systems will increase in magnitude.

    Scientists are already experiencing major diffuculties in trying to convert nuclear energy to electrical - so maybe there has to be another way? - I am simply postulating this - I mean surely there been research done into this? - Other forms of energy transfer?
     
  9. Apr 27, 2006 #8

    ZapperZ

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    Whatever it is, it certainly has not been using muons considering the ADDED problems and issues surrounding them.

    Zz.
     
  10. Apr 27, 2006 #9

    Astronuc

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    Energy losses during transmission are not so significant as compared to the inherently limited efficiencies of current thermdynamic cycles. For example, in most commercial nuclear power plants, the conversion from thermal to mechanical energy is about 33%, based on the steam Rankine cycle. Increasing the temperature to that used in coal plants could increase efficiency to 37-38%. Improvements in turbine design have actually increased the efficiency of the most modern nuclear plant to about 36% or so. Gas-cooled reactors have a potential efficiency of 42% based on much higher steam temperatures.

    HOWEVER, there is a problem associated with higher temperatures and that is degradation of the structural materials over time. That involves corrosion, erosion and creep (mechanical deformation) which degrades performance and ulimately leads to 'failure' of the system. Certainly one can replace a component before failure, but replacement costs money.

    Aeroderivative gas-fired (natural) gas turbines can get about 42-45% efficiency (Brayton cycle), and if one adds a steam (Rankine) cycle on the back end to catch the output of the Brayton cycle (for a so-called combined cycle plant), one can realize about 60-62% conversion efficiency.

    Still, fusion plants with 'direct conversion' would theoretically obtain efficiencies of something like 85-90%. BUT, commercially developed fusion is still theoretical (hypothetical).

    Transmission losses are about 1 to a few %.

    Superconducting transmission lines would be nice, but are impractical given the length of lines and necessary cooling over such distances.
     
  11. Apr 27, 2006 #10

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    In relation to the last post, by astronuc, one can easily see the energy conversion rates - in terms of the efficiency of current reactor/generator systems. Though these are the efficiencies now, future designs will obvisouly increase in efficiency - even if by a little, to a value which will approach closer and closer to the actual physical limit.

    But again I mention that I was not initially talking about the in-efficiencies of converting energy from one form to another (as done by a reactor/generator assembly), nor the losses incurred in electrical systems. Merely, that we are physically limited by the amount of energy that electrons can transfer to appliances, which are due to factors such as speed, mass and forces applied (of and by the electron). These physical limits are due to the particle and its interaction in an electrical system. I was wondering if there was any work done into other 'particle-energy-transfer' methods, apart from using electronics?

    And yes, Zapper, it has been mentioned several times that the muon is un-plausable for this - this was merely an example to convey the idea.

    I mean, if we increase efforts in space exploration, one can understand that energy requirements will gigantically increase. Also the method of trying to convert one form of energy to electrical - like nuclear scientist are working on, more so for fusion, is a rigorous and lengthy battle , simply just trying to convert the energy. If other methods were hypothesised maybe we could eliminate using other forms of energy to turn a generator - which already has limits - and be looking at a new branch of energy tranformation and supply? > surely this has been postulated somewhere.
     
    Last edited: Apr 27, 2006
  12. Apr 28, 2006 #11

    ZapperZ

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    But see, this is what you keep missing. Most of us DO NOT SEE that there is any "problem" here. It has been mentioned several times that the electrical conduction is not where the problem lies. If we ever get room temperature superconductors (probably not in my lifetime), then this issue is even moot. You are talking about trying to eliminate probably less than 10% of the total energy loss in the whole transfer chain. So it is puzzling the rest of us why you are picking on this 10%, while you are ignoring the source of the other 90%.

    One would think you would put more emphasize on the main culprit. Try justifying that to a research funding agency.

    P.S. There ARE other means of energy/signal transfer. Optoelectronics and spintronics are ways to transfer signal in "circuits" from one location to another. However, these can only carry a small amount of energy at any given time and does not approach the amount of energy that a typical household circuit has to transfer.

    Zz.
     
    Last edited: Apr 28, 2006
  13. Apr 30, 2006 #12

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    I have already mention 3 times that I am not talking about in-efficiencies in an electrical wire - try and read the posts carefully. Who is interested in 10 % losses - did I not mention that these systems will get more efficient as technology progresses ?

    I am simply saying that energy production at the moment is concerned with developing systems (such as nuclear - fusion, and others) to turn a electrical generator. Trying to convert energy from one form to another (i.e. creating fusion reactions to turn the generator) has massive problems. Is there not any other ways of providing energy rather than trying to turn a generator? - Supplying energy without using electronics, - perhaps other forms of particle collisions?

    Nobody has mentioned transferring signals?
     
  14. May 1, 2006 #13

    Astronuc

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    The first paragraph mentions copper wire and "the electrons are slammed across the resistors connected to the wire, applying energy to them." The only reason to generate electricity is that it is "transmitted" by a continuous network of wires from source (generator) to user (lights, appliances, machines). The major inefficiency has to do with thermal to mechanical conversion. The conversion efficiencies from mechanical to electrical and in transmssion are relatively high.

    Direct conversion in an MHD/plasma system might achieve 80-90%, as opposed to the efficiency of a steam (Rankine) cycle of ~34-38%, or gas combustion system (42-45%), or combined cycle (60-62%). Electrons are still involved since atoms are composed of nuclei (p and n) and electrons. Other particles don't enter into the process - except for gamma rays in fission and fusion - and they are not useful sources for electrical energy.

    One is pretty much stuck with chemical energy, nuclear energy, or more benign forms such as solar energy (PV), wind energy or hydroelectric.

    Fusion is problematic at the moment regardless power conversion method.

    Microwave? Need line of sight to avoid significant losses, and one would need a lot of antennaes at source and user points.
     
  15. May 1, 2006 #14

    Morbius

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    Because that's where the real problem is - where do you get the intial source of energy.

    Not really - fusion reactions can give you heat - and we know how to turn heat
    into electrical energy just as we do now.

    Transferring energy via heavier particles is going to be more inefficient than electrons.
    Heavy particles don't like to travel through materials - and they lose energy as they
    do. The movement of electrons through metals is many, many orders of magnitude
    more efficient than other particles.

    In essence, we're already using the "best" particle for transferring energy - and that
    is the electron.

    Dr. Gregory Greenman
    Physicist
     
  16. May 1, 2006 #15

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    So your saying that there isn't major problems with fusion reactors (i.e. tokamak - ITER, ect.) and trying to convert the little plasma achieved (due to low density) into turning a generator?

    Yes but I am saying that we are focussing on converting one form of energy to another (mainly fossil or nuclear --> electricity) by turning a generator. You and various other people have mentioned that the problem lies in the inefficiencies of the coversion of mechanical energy to electrical (other posts mention 30%-60% for steam/generator cycles). I am not intrested in these inefficiencies - I am talking about the physical limitations of electricity (i.e. electrons, their mass and speed - slamming into resistors and applying energy) - and if there is other methods that have been previously theorised, hypothesized or looked into to do with other forms of energy transfer - INSTEAD OF USING ELECTRICITY - use some other particle/energy/transfer system. I am not intrested in turning a generator because I am talking about electricity, I am talking about other supposed methods of energy transfer to devices.

    Yes, thats a nice summary of modern particle physics and energy transfer. I was actually referring to the existence of credible data that supports that fact; that currently with our knowledge of physics, the electron is indeed the best candidate for energy transfer. Even though this is true currently (simply because it is use), has there been work done on other possible methods? - This is an area in physics that seems to be non-existent.

    In the future when we have worked out these small inefficiencies with the transfer of mechanical energy to electrical, surley electrical energy will have a physical limitation to energy transfer. What then - how will we continue to advance upon energy transfer? I mean electricity will be at its maximum potential - will this be enough for energy requirements in the human races advancement into space?
     
    Last edited: May 1, 2006
  17. May 1, 2006 #16

    ZapperZ

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    So you either didn't care, didn't read, or simply didn't understand the other examples that I gave on possible signal/energy transfer using opto-electronics and spintronics?

    And what exactly is the "physical limitations of electricity"? Electrons don't "slam" into resistors in a superconductor, so this really, in principle, shows that in principle, "resistors" can be insignificant. So what else?

    Zz.
     
  18. May 1, 2006 #17

    Astronuc

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    Fission and fusion produce thermal energy by virtue of the kinetic energy of the products. This thermal (kinetic energy) has to be converted into a form that can be transmitted.

    If one uses electromagetics (photons), then the kinetic energy of the fission or fusion products has to be transformed into photons - by excitation of some material, then the photons have to be collected and directed into some transmission system.

    As for the examples ZapperZ mentioned, opto-electronics and spintronics, they appear suitable for transmission of low energy densities.

    Spintronic devices are used in the field of mass-storage devices, not power conversion.
    http://www.nanotech-now.com/spintronics.htm
    http://www.glue.umd.edu/~jfabian/spintronics.html

    Opto-electronics seems to be a broad field, including lasers, but I find no examples of power conversion systems.

    The Optoelectronics Group (http://www.ee.ucla.edu/~photon/) at the UCLA School of Engineering and Applied Sciences focuses on optoelectronics, high speed optical communications, high efficiency light-emitting diodes and nano-cavity lasers, photonic crystals at optical and microwave frequencies, and quantum computing and communication. However, power conversion does not seem to be a factor.
     
  19. May 2, 2006 #18

    Morbius

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    You have a misconception of how you get energy from a fusion prlasma. You don't
    get the energy from the low density plasma. You have to study up on the physics
    here. In the most probable fusion reaction that would be used - "D-T fusion", there
    is an energy realease of 17.6 MeV of energy. Of that only 3.5 MeV goes to an alpha
    that can be trapped by the plasma. The rest of the energy, 14.1 MeV; goes into the
    neutron produced in the reaction.

    When a fusion plasma ignition is achieved - it will be a large neutron source - and
    most of the energy it produces will be in these neutrons. The neutrons and their
    energy will be captured by a "blanket" probably in the form of a "shower" of liquid
    lithium. The neutron energy will be captured as heat in this "blanket" which will be
    cooled - and the energy used to generate power in a conventional manner.

    WRONG!!! The inefficiency is NOT in the conversion of mechanical energy into
    electrical - that process is VERY efficient. The inefficiency is in the conversion of
    HEAT to mechanical. There are very good reasons WHY - due to the physics - that
    this must be so.

    Your whole way of thinking about this is in error. Electrons don't "slam into
    resistors"

    If you think that this is an area of physics that is "non-existent" - then you haven't
    studied the physics. Additionally, I wasn't talking about "particle physics" in the
    way that term is used in physics. I was talking about how these "non-electrons"
    that you want to have tranport energy will do the job.

    We know very well the physics of how particles transport through matter - which
    happens to be my particular specialty. These other particles are going to LOSE
    ENERGY at a rate MUCH GREATER than the passage of electrons.

    Most of the "volume" of an atom is taken up by the "electron cloud" - the nucleus is
    a very small portion of the atom by volume. As electrons flow through a metal or
    other conductor - they are essentially "handed off" from one portion of the electron
    cloud to another. Electrons have an easier time "flowing" through this cloud because
    they are the same type of particle as the cloud is made of . Other particles would
    react with, and and disturb the electron cloud - which would result in energy loss. For
    example, any positively charged particle would feel a continuous "drag" force in
    traversing through the negatively charged electron cloud.

    You have to dispel yourself of this notion of "electrons slamming into resistors" -
    because it is just plain flat out WRONG - the physics doesn't work like that. When
    you study how electrons and other particles truly do move energy - a field that is
    very well understood - then you'll see why we use electrons.

    Dr. Gregory Greenman
    Physicist
     
    Last edited: May 2, 2006
  20. May 3, 2006 #19

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    Who is intrested in transferring signals and small amounts of energy? How can this be used for large scale energy transfer like electricity - it can't.
    Opto-electronics, electro-optics and spinotroics are basic forms of small signal and energy transfer (astronuc metioned this - the "transmission of low energy densities", optical telecommunications, LED's) - these are tought in high school - nobody is talking about this...
    Furthermore I was talking about electrical conductors (wires) and how electrons are applied across resistors ( i.e. Alternating Current) transferring their energy to them. - I havn't mentioned anything about room temperature superconductors and what not...

    Firstly what is prlasma?
    Secondly nobody is saying that nuclear engineers are using low density plasma to do anything. All I was saying is that the tokamak (and similar fusion reactors) are currently unsucessful because they achieve creating low density plasma through nuclear reactions. This is not sustained for very long and therefore is not sufficient for power production. Furthermore the nuclear energy from this is siphoned off to create electricity - so you must turn a generator. Whether you collide these particles into a "blanket" to produce heat which creates stem and then turns a generator is irrelevant - the heat is used to operate mechanisms (generator/magnet assembly) which create electricity.

    Indeed the inefficiency is in coverting the initial form of energy to cycle (or turn) the generator - this was a error on my part. I should indeed say this instead of saying that it lies in converting mechanical to electrical. However, it is in the mechanical stage that the inefficiency lies since the initial energy source (fossil, nuclear ect.) which is used to create steam is considered apart of that system.

    Obvisouly using other particles in a manner that is similar to the nature of the electron is improbable - since the metallic lattice (combined of cations, localised and delocalised electrons) is a already viable state which occurs in nature. However magnetohydrodynamics is an area which seems to hold plausible prospects for future efforts in using nuclear reactions to create energy.
     
    Last edited: May 3, 2006
  21. May 3, 2006 #20

    ZapperZ

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    Whoa nellie! Remember, YOU asked this:

    OTHER METHODS! And so I brought up OTHER METHODS that have been experimentally shown. And even *I* have mentioned why these are NOT considered as feasible. You asked if there are others. I showed you examples and why they aren't feasible! You continue to ask why aren't there examples. I told you again about these and why you ignore them. And now you're telling me you don't want these because they carry such low energy! Well of course! I have said that already! It was my point that there have been other methods of transfering signals and energy, and they all cannot do what simple electricity can do.

    And superconductivity IS relevant to this because of your wrong impresson of what "resistance" actually is! If I can remove resistivity in the transport of energy, then do you still have an issue to discuss?

    Wait a second. You want to deal with MHD, but then you asked this?

    Er.. what gives? Shouldn't you understand plasma physics first before jumping into MHD and touting it as the next best thing since sliced bread?

    Zz.
     
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