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Communications Wireless Networking Network Power Science

'Rectenna' Harvests Electromagnetic Energy From 5G Signals (interestingengineering.com) 127

An anonymous reader quotes a report from Interesting Engineering: In a world-first, a team of researchers at the Georgia Institute of Technology has developed a small, 3D-printed rectifying antenna that can harvest electromagnetic energy from 5G signals and use it to power devices, in a way turning 5G networks into "a wireless power grid," according to a press release by the university. As explained in the Jan.12 issue of the journal Scientific Reports, the flexible Rotman lens-based rectifying antenna, in other words, rectenna, system can perform millimeter-wave harvesting in the 28-GHz band. Commonly used in radar surveillance systems to see multiple directions without moving the antenna system, the Rotman lens is especially important for beamforming networks. However, larger antennas, which unfortunately have a narrowing field of view, are needed to harvest enough power to supply devices, and this limits the usage.

The researchers solved this problem by using a system that has a wide angle of coverage. The Rotman lens provides 6 levels of view at the same time in a pattern shaped like a spider. By enabling this structure to map a set of selected radiation directions to an associated set of beam-ports, the lens is used as an intermediate component between the antennas and the rectifiers. This way, the electromagnetic energy collected by the antenna arrays from one direction is combined and fed into a single rectifier. This maximizes efficiency, enabling a system with both high gain and large beamwidth. The system achieved a 21-fold increase in harvested power compared with a referenced counterpart in demonstrations. It was also able to maintain identical angular coverage.

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'Rectenna' Harvests Electromagnetic Energy From 5G Signals

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  • rectenna ? (Score:5, Funny)

    by Anonymous Coward on Tuesday March 30, 2021 @08:05AM (#61216816)

    They seriously couldn't come up with a name which wasn't immediately going to be a source of butt jokes?

    • by DontBeAMoran ( 4843879 ) on Tuesday March 30, 2021 @08:31AM (#61216898)

      It's still better than anustenna.

    • Re:rectenna ? (Score:5, Informative)

      by Geoffrey.landis ( 926948 ) on Tuesday March 30, 2021 @08:45AM (#61216956) Homepage

      The word "rectenna" *short for rectifying antenna) has been around for fifty years. The new thing about this is not the rectenna; that's old. It's the operation at 28 GHz, and the ability to rectify waves from a wide variety of incident angles.

      • So antennas can operate at 28GHz but Intel can't even operate their CPUs at 5GHz?
        Lame.

        • Re:rectenna ? (Score:5, Informative)

          by UnknownSoldier ( 67820 ) on Tuesday March 30, 2021 @10:59AM (#61217428)

          1. Silicon doesn't reliably scale past 5 GHz. It is the elephant in the room.
          2. We've had 500+ GHz CPUs (GaAs) for over 20 years. You can't afford the cooling bill.

          • 2. We've had 500+ GHz CPUs (GaAs) for over 20 years. You can't afford the cooling bill.

            No we haven't. Not even close by 2 orders of magnitude. We've multiplexed data with frequencies at 500+GHz, we've manipulated a signal at those frequencyes, but we sure as heck haven't don't any actually calculation or "processing" at that clock rate. Long before then you end up with a speed of propagation problem where data arrives at different parts of the die out of sync with the clock signal.

            • Long before then you end up with a speed of propagation problem where data arrives at different parts of the die out of sync with the clock signal.

              A rule of thumb: light travels about a foot in one cycle of a 1 GHz oscillator. At 4 GHz, about 3 inches.

        • by hawguy ( 1600213 ) on Tuesday March 30, 2021 @05:00PM (#61218662)

          So antennas can operate at 28GHz but Intel can't even operate their CPUs at 5GHz?
          Lame.

          28Ghz is nothing, I've got antennas all over my house that transmit in the 400-800 terahertz range. My watch even has a collector that can collect energy from that frequency range.

      • What's new is people thinking "rectal", but somehow thinking that 1. that matters (Come on, you buy by name? That's pathetic.), 2. what their mind comes up with somehow is somebody else's fault.

        Ok, for true passive-thinker drones, I can see that. But those by definition chose to not be people. So it depends on how their swarm thought leader interprets it. And then, for him, my points are true again.

        You can see another example of point 2 whenever religious fundamentalists terrorize any form of nudity or sexu

      • The word "rectenna" *short for rectifying antenna) has been around for fifty years.

        As little as that? I'd have thought that the combination of a length of wire and a carefully-tickled cat's whisker would have packed "rectifier" and "antenna" into a portmanteau back in the 1920s.

        Wiki-ing it [wikipedia.org], commercial sets were available before 1915.

    • "That's a nice antenna, but why would you stick it up your ass?"

      "Well, why would you *not* stick it up your ass?"

      • "That's a nice antenna, but why would you stick it up your ass?"

        "Well, why would you *not* stick it up your ass?"

        Better signal-to-noise ratio I guess, but that all depends on the individual.

        Some people, have a lot of gauss..

    • As soon as I read "rectenna" my mind immediately went to Eric Cartman with the satellite dish sticking out his butt.
    • They seriously couldn't come up with a name which wasn't immediately going to be a source of butt jokes?

      Well, to be fair the original name was “Amplification Networked Universal Supply” which is a bit of a mouthful.

  • So if everything starts powering itself with 5G signal, will we need more transceivers to compensate for the lost transmission energy? Will it increase costs?
    • I know, I had to check that is wasn't April 1st yet.
    • by e3m4n ( 947977 )
      Energy cannot be created or destroyed, only altered in form. That prettymuch answers your question right? By definition its acting as resistance.
      • Every slashdot reader knows that resistance is futile.

      • by HiThere ( 15173 )

        OTOH, it's only intercepting an extremely small part of the signal. It should only affect those in the shadow cone of the antenna...and that would usually be nobody.

        • by e3m4n ( 947977 )

          OTOH, it's only intercepting an extremely small part of the signal. It should only affect those in the shadow cone of the antenna...and that would usually be nobody.

          No it becomes an EM black hole. This isnt new. Its how your microwave works. Except with 2.5ghz water is your cross sectional antenna. This is why you need more time when you have 8 chicken nuggets instead of 5. Otherwise the same time would work regardless of the mass of the food.

          • by HiThere ( 15173 )

            re: "No it becomes an EM black hole."

            I can't tell whether you're serious or not. My first reaction was "How would that work?", but on rereading I couldn't decide whether you were serious, sarcastic, or seriously confused.

      • It's not that simple though.
        There's quantum foam of the vacuum, Hawking radiation, and of course it must only be conserved for the entire universe. So over small or short times, that limitation is not such a hard rule.
        It's just difficult to communicate that without the Free Energy nutters jumping onto it and misinterpreting.

      • Re:Less distance? (Score:5, Informative)

        by v1 ( 525388 ) on Tuesday March 30, 2021 @09:35AM (#61217148) Homepage Journal

        Very close to 100% of the energy from a cell tower is being lost as heat in the atmosphere. Only an extremely tiny fraction of it is doing actual work inside a cell phone.

        Radio waves obey the cube law in space, so the signal from the tower tends to be pretty strong to get out to the phones. Fifty watts out the antenna could result in something like 20 microwatts in a cell phone a mile away.

        If you're sticking an antenna up in the air to "harvest power" you're (A) not going to get very much and (B) only going to present an extremely small "shade" to devices on the other side of you from the antenna. The refrigerator in the house next door will do more to shade your cell phone than any harvesting antenna will. And both will have an equally small location being shaded. Your cell phone crosses through hundreds of these regions every minute as you drive along the road. Back in the analog phone days you could hear the signal quality dipping, but with digital error correction now you either have it or lose it so you don't notice areas of lower signal until the phone drops the call.

        I'd really like to know how much power they're able to get out of the air. And I'd be impressed to hear more than one or two milliwatts. But whatever it is, it's sure as heck not "robbing" anything of power.

        I suppose if I had to make an analogy, imagine a gymnasium with one of those giant floor fans, and there's these little hand-held pinwheel scattered all around the room, turning (slowly, for the most part) in response to the air circulation in the room. Now someone holds up a post-it note to see if they can get the paper to bend a little. (A) the paper isn't going to move much, and (B) it's not going to have any effect on the pinwheels in the room. And compare all of that to the enormous amount of air the fan is moving. Even if you got "crazy" and stuck a huge 8.5x11 paper up in the air to increase your capture, nothing's going to change, except maybe one very unlucky pinwheel that happens to be right next to it and in a very unfavorable orientation

        • by e3m4n ( 947977 )

          Very close to 100% of the energy from a cell tower is being lost as heat in the atmosphere.

          So we could trigger the bandwagon global warming alarmists to eliminate cell towers to help fight global warming? That could be fun. I get its a small percentage but when has that ever stopped a fanatic?

        • by e3m4n ( 947977 )
          Your paper theory holds no weight beyond an experiment. If I am pumping 200KW into atmos, if everyone starts sucking 5kw off that signal, eventually it will be noticeable once 10 people do it. Now lets say they think they can power a smartphone. Lets say thats 30watts. Your still gonna suffer a LOT of attenuation considering how many phones there are. So now in any setting there are a hundred postit notes surrounding your pinwheel.
          • Re: (Score:3, Informative)

            by habig ( 12787 )

            No, that paper theory is right on track. The power available to any given square meter falls off as 1/r^2. So, if your 200kW is being broadcast uniformly into a hemisphere it's 1/(2pi r^2) (probably not actually uniformly, but hey, I'm a physicist so spherical cows). So, if you're 1km away and holding up a square meter antenna, is at most going to result in you and your square meter seeing 32 mW.

            Someone standing behind you won't be able to get the 32mW your square meter already sucked up, they're in its

          • by v1 ( 525388 )

            Your paper theory holds no weight beyond an experiment. If I am pumping 200KW into atmos, if everyone starts sucking 5kw off that signal, eventually it will be noticeable once 10 people do it.

            Let me put it in a way that's easier to understand. Instead of invisible radio waves (that too many people seem to regard as "magic" for purposes of analysis) lets replace it with something easy. A 100w light bulb in a room with black walls (so no reflected light) So a 100w bulb in the middle of a big room. And you

            • by e3m4n ( 947977 )
              Have you never held down the key on a cb or ham radio and prevented someone from talking on the same channel?
              • by v1 ( 525388 )

                Have you never held down the key on a cb or ham radio and prevented someone from talking on the same channel?

                (I've held a radio license for several decades now actually) That would be adding more energy into the system, though I don't see how that applies to the mistaken idea that radiant energy can be stolen by adding more receivers. That's just jamming / overload, not taking away power.

                A better radio analogy might be to ask that if I was talking with a friend across town using very low power and suddenl

        • But whatever it is, it's sure as heck not "robbing" anything of power.

          Well it is, just with a really tiny amount. The refrigerator next door is likely reflecting power so not robbing anything. Those bricks in your house though, oooh crafty thieves they are.

        • Radio waves obey the cube law in space, so the signal from the tower tends to be pretty strong to get out to the phones. Fifty watts out the antenna could result in something like 20 microwatts in a cell phone a mile away.

          I thought it was the inverse square law for the reason that the surface of a uniformly radiating point source is a ball with an area of 4 pi r^2. (Conservation of energy and geometry are why we have lots of inverse square laws.)

          This gives about 0.0149 microwatts (-48 dBm) at a 15 inc

    • No, we just power the 5G transceivers with more rectennas.

    • So if everything starts powering itself with 5G signal, will we need more transceivers to compensate for the lost transmission energy?

      No, because they can only harvest what the tower is transmitting. They can't tell the tower to increase its output.

      Plus: They can only harvest as much as the area covered by the receiving dish, ie. bugger-all. A tiny solar panel will harvest much more.

      ie. This is a non-story.

      (apart from the stupid name)

      • This ^

        Basically the signal strength put out by LTE/5g/two way radio is small, even in strong areas is 40 dBuV/M (0 dBu is one microvolt per meter). This means that in a strong area there is 10 Millivolts per meter, and a perfect antenna capturing 1m of free space is going to capture this voltage across the impedance of free space. In terms of power this works out to microwatts.

        There is not enough power to do anything with.

  • by gweihir ( 88907 ) on Tuesday March 30, 2021 @08:11AM (#61216834)

    Talk about an unfortunate name choice....

    Incidentally, doing this is illegal at least in parts of Europe.

    • Re: (Score:2, Informative)

      by e3m4n ( 947977 )
      As it is here. It is not FCC compliant as it interferes with the signal. The first law of energy conservation is that energy cannot be created, nor destroyed, only altered in form. They are literally stealing the sognal energy (stength) to power a device. This in turn weakens the signal. The FCC plays no games about signal interference, and gives no fucks about ass raping you in legal battles. Every broadcast company out there pays them to ass-rape any sort of signal interference and pirate radio.
      • Anything like "stealing" ones and zeroes and how it weakens the value of the item?

      • As it is here. It is not FCC compliant as it interferes with the signal.

        So do antennas and walls and people and just about anything else in the millimeter band.

        The first law of energy conservation is that energy cannot be created, nor destroyed, only altered in form. They are literally stealing the sognal energy (stength) to power a device.

        Antennas literally steal signal energy.

        • Well except for one VERY (and it's a biggie) difference. Anything used for communications is going to have amplification. In other words using it's own power to make the incoming signal bigger. For something "stealing" power, adding your own runs counter to that ethos.

        • So do antennas and walls and people and just about anything else in the millimeter band.

          Now, if the harvester is sending messages to the cell tower to induce it to transmit more power its way, that would be a bit different. (Like maybe it fake-registers with the tower constantly, or places a call to a recording that just plays noise constantly or something - although this would require paying the provider, so...)

          Anyways it's kind of a silly argument, all tech can be used in an illegal manner (to hit pe

      • by Geoffrey.landis ( 926948 ) on Tuesday March 30, 2021 @09:35AM (#61217146) Homepage

        ...They are literally stealing the sognal energy (stength) to power a device. This in turn weakens the signal...

        No, they're not, and it doesn't.

        The proposal is to convert radiated power. The power has been radiated already; it's gone whether or not you convert the part the passes through the device. If it were near-field power, you'd be right, but it isn't. If you don't grab it, it continues on until it's either absorbed by something else (vegetation, the earth, humidity in the atmosphere) or radiated into space, but in any case, it's gone.

        But: it's very little power. A typical power density for 5G might be 1 watt per square meter (about 1/1000 sunlight intensity). For these tiny devices, you might harvest fractions of a milliwatt.

      • by AmiMoJo ( 196126 )

        If they got permission to harvest that energy this could be quite useful. There are many applications where there might be a special case to allow a number of such devices to harvest energy.

      • As it is here. It is not FCC compliant as it interferes with the signal.

        You're not FCC compliant either, just by sitting where you are you're interfering with the signal. The reality is the FCC rules are more nuanced than that. So nuanced in fact that they didn't immediately deem anything that contains an antenna illegal, which is incidentally what you're implying.

    • by Gonoff ( 88518 )

      Incidentally, doing this is illegal at least in parts of Europe.

      and compulsory in conservative groups across the world. Remember the acronym BOHICA!

  • Didn't Nikola Tesla build the Wardenclyffe Tower on Long Island, NY to wirelessly transmit power?
  • Oh no (Score:4, Insightful)

    by majorprecedent ( 7926114 ) on Tuesday March 30, 2021 @08:14AM (#61216840)
    5G nuts are gonna have a field day with this one.
    • Just imagine if one of them wears a tinfoil hat and sparks appear when they get close to a tower!

      • Instead of a tin foil hat they could wear a Rotman lens and it would harness all of the 5G energy and prevent it from getting to their brains.
  • by gb7djk ( 857694 ) * on Tuesday March 30, 2021 @08:20AM (#61216850) Homepage
    There have been a (smallish) number of successful prosecutions of people (mainly farmers "stealing electricity" from nearby transmitters). One example that springs to mind was a farmer whose cowshed was 200m from the 198Khz BBC Radio 4 transmitter. He lit the shed with some fluorescent tubes with bits of wire on each end acting as antennae (or electricity pickups as, I believe, the prosecution called them).
    • by WoodstockJeff ( 568111 ) on Tuesday March 30, 2021 @09:45AM (#61217180) Homepage

      You mean they outlawed crystal radios [wikipedia.org]?

      The only real difference is the amount of power collected and the tuning. If your receiver didn't "catch" the power, it would have dissipated into other objects (or space).

      • by gb7djk ( 857694 ) *

        Crystal sets - are legal for receiving broadcast stations - as they are nothing other than a 'tuned receiver' doing what they are meant to to do and do not leach (meaningful amounts of) power from the air.

        In the UK you are only licenced to receive broadcast radio signals (yes; the government 'holds' your receiving licence for you; even today; even in this day and age) - note that it does not matter WHAT is being broadcast (AM; FM TV DAB etc). Use of radio receiving apparatus for any other purpose (unless ex

    • by AmiMoJo ( 196126 )

      More common is for people who live under power lines to do it. You don't even need wires for low levels of light.

      I had a little clock running off a TV antenna with a Dickson charge pump many years ago. We are talking microwatts of energy so I doubt anyone would have cared, and I never got "caught".

  • by way2trivial ( 601132 ) on Tuesday March 30, 2021 @08:24AM (#61216868) Homepage Journal

    Just because you 'can' does not mean you can.

    https://www.industrytap.com/el... [industrytap.com]

    " A farmer in Idaho had a barn located near high power lines and noticed that baling wire he kept in his barn was conducting small amounts of electricity. After some investigation he built induction coils and began to run his house off of it. Power company equipment detected the drain of energy and went to investigate. The farmer was arrested for using electricity from the power company without a meter."

    • Re: (Score:2, Informative)

      by lenoc60877 ( 7381256 )
      Again: these "farmer stories" are made up. These are fake stories created to sell these wireless harvesting scams by convincing you that you can harvest a significant amount of energy using whatever snakeoil device they are selling. WHY DO PEOPLE CONTINUE TO BELIEVE EVERYTHING THEY READ ON THE INTERNET? Everyone needs to go back to Physics class again.
      • Re: (Score:3, Funny)

        by tigersha ( 151319 )

        Donald Trump: It's real, it's all over the Internet!

        Well, Melania's tits are all over the internet and they are not real either

      • Re: (Score:3, Insightful)

        Again: these "farmer stories" are made up.

        Indeed, the source is not what I'd call reliable, but actually the physics is credible. It's talking about harvesting power from the fringe-fields of high-voltage transmission lines. This is near-field power, not about RF power at all (if it were radiated power, the power would have been lost whether or not the farmer harvested it.). That's not really even very hard to do; half the museums in America probably do electricity shows in which fluorescent tubes are lit from near-field power.

      • Again: these "farmer stories" are made up. These are fake stories created to sell these wireless harvesting scams by convincing you that you can harvest a significant amount of energy using whatever snakeoil device they are selling. WHY DO PEOPLE CONTINUE TO BELIEVE EVERYTHING THEY READ ON THE INTERNET? Everyone needs to go back to Physics class again.

        I didn't read it on the internet. A relative working at a German radio station told me - personally - that he personally called TV licensing to get on a farmer's case who refused to stop draining their radio signal. Because it was his job to keep world wide transmissions going without interference.

        • by Ozoner ( 1406169 )

          Broadcast Transmitter sites often have a parasitic tower to place a notch in a certain direction to protect another station on the same frequency.

          But to be reasonably efficient, these parasitic towers are huge, at least as large as the main transmitting mast.

          A farmer who used relatively short lengths of wire to "harvest power" is going to have a negligible effect on the radiated signal. It it did work, then all of the fences and metal clad barns in the area would need to be torn down.

          Whatever, none of this

    • Definitely theft.

      I pay for that electricity. And I pay more to keep a stable signal despite some fucker weakening it. So in fact it's *double* theft.

      • by ghoul ( 157158 ) on Tuesday March 30, 2021 @09:21AM (#61217096)
        Well when the electricity company took the lines over the farmers land they signed a contract saying it will not affect the surroundings. Obviuosly the cheapskates used less shielding than required so the waves are leaking and affecting the environment. The farmers action are one way of pointing out the breach of contract. Now that the electricity company has proven that its their electricity affecting the farmers barn they cant defend themselves in a civil damages suit saying its not. Legal Judo!!!
    • " A farmer in Idaho had a barn located near high power lines and noticed that baling wire he kept in his barn was conducting small amounts of electricity. After some investigation he built induction coils and began to run his house off of it. Power company equipment detected the drain of energy and went to investigate. The farmer was arrested for using electricity from the power company without a meter."

      What do induction coils have to do with the topic at hand?

      • The radio energy used by the receiver has to come from somewhere, and it has to come from the transmitter because there's nowhere else for it to come from.

        More energy is used to amplify the signal, and it doesn't come from the radio signal obviously, but something of the signal still has to be used by the radio.

        If you use a rectenna field to receive a power transmission from a solar power satellite, the same thing is happening. Well, it would be, anyway. :) And the power would definitely be coming from the

        • The radio energy used by the receiver has to come from somewhere, and it has to come from the transmitter because there's nowhere else for it to come from.

          More energy is used to amplify the signal, and it doesn't come from the radio signal obviously, but something of the signal still has to be used by the radio.

          If you use a rectenna field to receive a power transmission from a solar power satellite, the same thing is happening. Well, it would be, anyway. :) And the power would definitely be coming from the transmitter.

          The correct answer is nothing.

          With induction coils you are getting water by drilling a hole into a pipeline and diverting water out of it.

          With an mm transmitter water is getting sprayed at everyone and everything in range of the nozzle.

          FCC has ZERO power to regulate in-path obstructions.

      • by sosume ( 680416 )

        Power company equipment detected the drain of energy

        There it is, fake news. How would they detect "a drain of energy" - there is none.

    • From the linked article:

      Power companies have sophisticated measuring equipment to detect losses of energy along their power lines.Â

      Not really. Or they would have the means to detect live lines rubbing up against trees and burning down towns in Northern California.

  • Well power source. But also simply a better 5G antenna.

  • by Ubi_NL ( 313657 ) <joris.benschop@[ ]il.com ['gma' in gap]> on Tuesday March 30, 2021 @08:40AM (#61216938) Journal

    I'm sorry but the word rectenna immediately reminds me of cartman's alien probe

    • I mean to me it immediately reminds me of an antenna that rectives to DCs, but then I did study EM theory as part of my engineering degree.

      I am however not an astronomer, so take a guess what Uranus reminds me of.

      • Not sure why I put an s on DC. But there it is my gaff for all to see.

      • by dgatwood ( 11270 )

        I am however not an astronomer, so take a guess what Uranus reminds me of.

        I'm sorry, thegarbz, but astronomers renamed Uranus in 2020 to end that stupid joke once and for all.

        • I am however not an astronomer, so take a guess what Uranus reminds me of.

          I'm sorry, thegarbz, but astronomers renamed Uranus in 2020 to end that stupid joke once and for all.

          yeah it is called urectum now

  • From the publication:

    ...and a harvesting ability up to a distance of 2.83 m in its current configuration and exceeding 180 m using state-of-the-art rectifiers enabling the harvesting of several W of DC power (around 6 W at 180 m with 75 dBm EIRP).

    So from a transmission power of 32kW (75 dBm), 6 W could be harvested... That is a loss of 96dB at 180 m... It might have some niche uses, but it won't be powering any significant devices... (There is a mu there, but it does not show up in the previews. All numb

    • If you saw that the mu wasn't rendered in the preview, then why didn't you rewrite it as "6 microwatts could be harvested"?
  • I wonder what the health effects of a full 5G deployment would be. If we are putting out enough energy that it can be harvested and mind you this is microwaves are we putting out enough energy to cook our brains slowly over time? I see applications for this device as a personal shield. Put it in tin foil helmet to protect your brain.
    • 5G tanning - patent pending - simply lay your 5G harvesting mattress under a 5G transmission tower and you'll achieve a bronze glow without the harmful associated with UV radiation from the sun.Best thing, you can at night when the sun is away.

      All for 4 easy payments...

  • Now watch the people, who claim to get issues from wifi signals, claim that this proves wifi is harmful and should be abolished.

  • Now, not only do I have to worry about IoT devices skipping my wifi network in favor of 5G to spy on me, but they can self power anything lying around to spy on me. Yeah, I really want your IoT cabinet spyware.

  • by MagicMike ( 7992 ) on Tuesday March 30, 2021 @01:47PM (#61218038) Homepage

    "around 6 W with 75 dBm EIRP) can be harvested at 180 m."

    https://www.nature.com/article... [nature.com]

    C'mon /. ya'll nerds or what? Everyone's all "their stealing power" and though I'm +1 on jokes about Cartman's alien experiences no one posted the power data.

    What can you do with 6 W - that's the question and the real nerd fun.

    Go

  • A 5G mast has a power of 44 Watt. It needs that power to transmit data to phones. If some idiot interferes with that, they cause damage to other people's phone reception.

    I know about a German radio station who had trouble with a farmer who managed to get strip lights working with the energy from the radio signal - which reduced the range of their supposedly world wide radio signal. They talked to him nicely, no result. Then they called the TV licensing agency. What he did fit exactly the description of r
    • by Ozoner ( 1406169 )

      Yes, he may have been required to pay a radio/TV license, but this has nothing to do with stealing power.

      The laws of physics tell us that the amount of power he could obstain would be far too small to affect the strength of the broadcast signal. If it was, then all of the wire fences and metal bards in the area would need to be town down.

  • The linked article and press release don't say how much power it can harvest - is it microwatts (which could be useful), or nanowatts (which would be hard to do anything with)?

  • > Power companies have sophisticated measuring equipment to detect losses of energy along their power lines

    This is nonsense.

    If the lost power was measurable, then a simple Transmission Line Analyzer (eg Pulse Echo Tester) could be used to pin-point exactly where the leak was, and how much power was leaking.

    In reality power which could be "stolen" would be far too small to measure.

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