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Stealing Electricity by induced EMF

  1. Aug 12, 2004 #1
    I was wondering just how possible it is to "steal" electricity by inducing an EMF near the transmission cable? Does the electric company have ways to detect this or have counter-measures set up? How big would the wire need to be and made of what material? I am very interested in how all of this works and I am thinking about writing an article about it as not many have heard of this. Most people think of stealing electricity as stealing someone's else's meter, but this method is quite infantile. Please keep details to a scholarly level and DO NOT post instructions on how to do it per se...

    Kristian Hermansen
  2. jcsd
  3. Aug 12, 2004 #2
    I've heard a story where a farmer whose barn was right underneath some high-voltage lines, set up many many copy coils in the barns roof and was able to steal electricity that way. The power company noticed because of the extra drain on the transmission lines there, or something like that and put a stop to it.
  4. Aug 12, 2004 #3


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    I've heard stories about farmers "stealing" energy from those megawatt AM stations by putting up antennas and rectifying the power. In some versions I hear that this was found to be perfectly legal, and the radio stations agreed to pay the farmer's electric bills if he'd only stop interfering with their broadcasts. In other versions, I hear that the farmer was ordered to stop. I don't know what the truth, if any, is. But I never heard about stealing through "EMF". You'd either want very high currents to tap into the magnetic field, or else very high voltage to tap into the electric field (but in the later case, if the field gets too high, the possibility of an arc-over from the HV to your equipment exists).
  5. Aug 12, 2004 #4

    Chi Meson

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    I've heard of farmers' cows "stealing" electricity from the overhead lines. They didn't enjoy it; they got a shock every time they took a drink of water. SOme poor farmer went out of business not knowing why his cows were perpetuately dehydrated.

    The amount of electricity you could "pull" out of the air using e-m induction would be miniscule from ground level (the two or three power lines operate out of phase and effects would cancel) and outright fatal at close range.

    That previous post about stealing AM radio power sounds neat, I'd try that first.
  6. Aug 13, 2004 #5
    Hidden induction tapping of anyone's electrical power source, commercial or private, is illegal. The reason is that it DOES reduce the power output of the provider without their permission.
    Aerial methods to extract DC from EM waves are common with any radio device(as that is how they function), but any concerted effort to set-up an aerial environment and use it to "gain or profit" to any substantive degree that notably effects provider services is prohibited. That is, create an aerial environment to extract radio waves to light an LED? Go for it. Do it to power your house and your neighbors reception is effected? No.
  7. Aug 13, 2004 #6
    BTW, the costs associated with setting up an aerial EM extraction of any usefulness would be so expensive that one's monies would be far, far better spent on a quality solar cell array(and with no legal if's!!)
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