TechCrunch Disrupt: Charging A Phone With Its Own Transmitter

TechCrunch Disrupt is on this week, and that means we get to see which members of tech media don’t understand basic physics. So far, it’s writers from Engadget, The Mirror, Business Insider, TechCrunch, and four judges on the TC Disrupt stage. What is the consequence of not understanding the implications of the conservation of energy? Glowing support for a cell phone that can charge itself.

The offending Disrupt startup is Nikola Labs, and they’re gearing up to launch a Kickstarter for a very special iPhone 6 case. This case uses small, energy-harvesting antennas to gather RF energy from the cellphone tucked away in this case. This energy is then sent to a rectifier where it is converted into something the Apple Lightning connector can sip power from. According to Nikola Labs, this RF harvesting antenna takes energy from the transmissions of the iPhone 6 entombed in this case, converts it to about 5 Volts, and uses that to charge the iPhone battery.

I know that seems difficult to understand, so here’s a simple analogy: you have a flashlight with a battery and a solar cell. The solar cell recharges the battery. If this were a Nikola Labs flashlight, you would recharge it by shining the flashlight onto the solar cell.

That is the simplest explanation of what the Nikola Labs cellphone case does, and illuminates the limitations of what it can do. If the ‘energy harvesting circuit’ collects power from the device it is recharging, it will reduce the transmission power of whatever is transmitting. With the cellphone case, you’re spending transmission power (plus efficiency losses) to recharge the battery. That means poorer reception and fewer bars. In the solar-recharging flashlight analogy, the flashlight would either be dimmer, or you could only use it part of the time.

It’s also why Nikola Labs claims their case will only recover 30% of the battery life of an iPhone 6; the battery isn’t solely dedicated to a transmitter – there’s a display and a CPU to account for in the power budget.

To Nikola Labs’ credit, this is at least a novel application of the RF energy harvesting trope that has been making its way around Kickstarter and tech blogs for a few years. Nearly every other RF harvesting idea that has been pitched in recent memory decouples the transmitter (or ‘generator’, I guess) with the product or receiver. The square cube law is an evil mistress, and if you’re wondering why these devices don’t work, [ch00f], a guy with an actual engineering degree, has a great writeup of one of these products over on Drop Kicker.

The Nikola Labs cellphone case bucks this trend by looking at the shortcomings of these devices; an RF rechargeable Bluetooth tag won’t work if you place it a foot away from a WiFi router, but it just might if you tape it to the antenna. This is the idea behind Nikola Labs’ invention: harvest energy from a few millimeters away from the cell phone’s antenna. According to Nikola Labs, their engineer, [Chi-Chih Chen] has a patent in the works for this. This patent application has not been published yet.

In theory, the Nikola Labs cellphone case will actually recharge your battery, but at a price: you’d be wasting your transmission power on recharging the battery. It’s a false economy that you’ll be able to fund on Kickstarter next month for $100 USD. If you’re only looking for more battery life, walk into any gas station, buy a $10 USB power bank/battery, and have enough portable power to recharge your iPhone battery to 100%. That’s not a sexy solution, it doesn’t reference [Nikola Tesla], and it’s not snake oil that tech media is lapping up like dogs. Pity.

109 thoughts on “TechCrunch Disrupt: Charging A Phone With Its Own Transmitter

  1. Ironic, they are named Nikola Labs and they want to file a patent on technology that their namesake developed over 100 years ago. Talk about the snake eating its tail!

    1. Kinda my thoughts. How can one patent the good ol’ “battery-less AM radio” germanium diode project that we all build with a toilet paper tube tuner lol. I’m wondering where they are gonna fit the TP tube ;) Agreed. I absolutely loathe fucksticks like the Nikola Labs crew. Probably an overambitious high school teacher trying to pad some CVs since “facebook Club” is not a thing (thankfully).

  2. I always wondered why my nokia phone ran down the battery faster when powered off. now I know, thanks hackaday for teaching me about overunity energy conservation.

    1. Not necessarily.

      A cellphone antenna is omnidirectional because you can’t know where the tower will be when you make the call.

      If the user just holds the phone in the right way, the energy harvester can recover the power going in the wrong direction at no expense to the actual transmission.

      1. “If the user just holds the phone in the right way, the energy harvester can recover the power going in the wrong direction at no expense to the actual transmission.”

        Uh, no not if they’re both a part of the same brick like device, that responsibility comes down to the placement the engineers come up with, your hands might add attenuation and possibly extra coupling though.

      2. Exactly, the thing isn’t ‘sucking’ energy it’s using the part of the energy in which it resides, so if you for instance have a phone in your pocket and on the body side you harvest the energy you would not only get the energy that is blocked anyway but you’d have the device take it in instead of your body. And we’d avoid the eternal discussion on how harmful it is to your body. The caveat though is that it might change the behavior of the antenna in the phone and that could possibly worsen reception in weak signal areas, although it might also instead improve the antenna, only testing can tell.

        1. Antennas that are tuned to a given frequency that are less than a wavelength apart are likely to de-tune each other. While this device would be able to be tuned to accommodate, the antenna structure in the phone wouldn’t, any would likely suffer pretty drastically as a result (3-6dBm would be a safe guess). Most LTE bands would need 6+ inches of separation or so before you could call it no impact.

        1. There are still people out there that say, my phone didn’t have that problem. If you had an iPhone 4, then you had the problem, it was a design flaw in every single iPhone 4. If a conductive finger bridged the gap in the side band (antenna), then reception bars would drop. Completely repeatable with any iPhone 4. Oh the power of denial.

      3. A more efficient way to get the same result as you describe would be to replace the “energy harvester” antenna with a piece of unconnected metal.

        This will change the radiation pattern of the antenna (same total power, different directions) in some way, and if the resulting pattern is more focused on the cell tower, then the tower will hear the phone better and the phone will automatically reduce power — thus saving the energy directly without any losses from repeated conversions.

        Well, except for the part as noted by Matthias that the extra metal may detune the phone’s antenna, causing internal losses. You really want your reflector/director to be farther away. But now it’s a little impractical for a phone case. Oh well.

  3. Until technology is developed to harvest energy from the entire RF spectrum at once in parallel. DC all the way up to gamma rays and everything in between (including IR from the human body), this is just another useless perpetual motion snake oil device.

      1. I dont know what kind of radios you have access to, but every radio I have used is band-limited. Please post a link to your radio that can receive the entire RF spectrum at once.

  4. The case essentially blocks the phone’s antenna, requiring it transmit at a higher power in order to meet the noise floor requirements…then puts a fraction of that power back into the phone.

    They should go all out, and put solar cells in front of the screen to capture the phone’s light output as well

    1. Imagine a iPhone case consisting of a AC Generator on a large treadmill! Free unlimited power for your mobile phone – as long as you dont mind having the jog at least 6mph and dont mind being stationary.

        1. Ya know the funny thing about that commercial, is if that were true, say use a generator at each house, instead of a grid based energy, the US would be energy independent. For every 1kw used at a house, an extra 2.2kw has to be generated to transmit the power over power lines, therefore consuming 3.2kw per 1kw needed. Local energy generation or on-site is the idea of the future, the question is just how. Direct solar energy is by far the best idea, but the tech just doesn’t have the advancement to make it work. The sun radiates 1kw per m^2, meaning a 2 meter^2 solar panel with 90% efficiency would power an entire house, pretty bad-ass if you ask me. But current panels are less than 20%. Wind power is great, but ultimately its solar powered as well, same thing with fossil fuels. Other than fission, fusion, or some other type of thermo-nuclear power, all power is solar power. But if one day, room-temperature superconductors, plus 90% efficient solar panels exist, then one plant could power an entire state, being just a few buildings in size, or just on-site generation.

          1. I am pretty sure transmission efficiency in the gridis over 90%, not 30% as you say it. Maybe you are considering the efficiency of the generator which would make no difference if it was one large at the plant or small ones at home.
            The solar panel calculation would make sense if the sun was shining all the time. But on average the number of sun hours you get per day might be something like 6. So you would need 4X. Even with this in mind and 20% efficiency you still require small enough area that it would fit most roofs. The problem lies in the fact hat solar panels are expensive(both money and energy to make) and you need to store the energy which is also impractical and expensive.

          2. Yes. There’s a lot of confusion there.

            But it’s true that if households generated their own electricity, even if out of gasoline, energy efficiency would improve by about 3x because the waste heat would be immediately accessible for space heating, water heating, cooking etc. etc. and it just turns out that typical household energy demands are roughly 2/3 heat and 1/3 electricity.

            2/3 of the primary energy we use on the grid is wasted because the production happens 200 miles from the point of consumption.

  5. Am I the only person who realises this is nonsense? Those radio waves are supposed to reach a base station. If you’re leaching them away, the phone has to transmit with more power, draining the battery.

    This is a solid-state perpetual motion machine! And as far as power saving goes, you’d be better off with an app.

    1. 1kwh per 10 meters per day, not actually that bad if it wasn’t for the cost and resources involved. and of course energy conservation says that the electricity is possibly coming from additional resistance (however small) placed on vehicles. Piezo trees at the side of the road would block noise pollution and use wind power, although I have no idea of the efficiencies. I read the phone article on engadget earlier and thought it must be external Rf sources, but I was looking at the mast close to my home a few weeks back and looked it up on-line and found out that even 100 meters away the inverse square law would mean I couldn’t power an led bulb.

      1. With care and a long enough wire (antenna), you can power a LED from latent RF in many locations – but it is a VERY long wire… And a VERY small amount of energy.

        1. When my grandfather was young he was doing measurements on a dutch radio transmitter. He found this huge gap in the signal. Turned out there was a farmer using the signal to power the lightning of his farm.

          1. That should have been quite obvious, because the radio stations back then weren’t many kilowatts strong.

            Suppose it’s a 100 kW transmitter. In order to capture 1 kilowatt to run ten lightbulbs, one would have to cover 1/100th of the radio horizon. It’s obvious that if the farm was even a mile away, the reciever would have to be the size of a mountain.

            So, obvious legend is obvious.

          2. Your lying old grandfather got the story wrong, it was a farmer running a gigantic coil near some high-voltage power lines. Every lying old man knows that!

          3. It is possible to siphon power from a line by setting up oil drums full of junk iron and wrapping a coil around them, then lifting the contraption perpendicular under the power line. That forms a sort of air-gap transformer that gives you a few watts.

            Mythbusters tried it, but they didn’t add the iron and they connected a bunch of small 110 V lightbulbs for a load, which have practically zero resistance when they’re cold, so they only measured an increase of about 6 millivolts when they lifted the coil up and called it busted. Since there was power but not enough to light up their bulbs, the whole thing was more or less shorted out.

            Of course they wouldn’t have showed it if it had actually done anything interesting, because the episode was about debunking free energy.

            But the power is there, and power companies are always on the lookout for people who try to pull off stunts like burying a bunch of old barrels with coils in them, because it shows up on their meters as power loss.

  6. Shining a flashlight at a solar cell does not reduce the brightness of the flashlight, nor does harvesting RF energy in proximity to a phone antenna reduce the output power. However, much as a solar cell can interrupt the light coming out of a flashlight, an antenna placed in close proximity to another can cause any number of issues with the transmitting antenna, including reflections, coupling, and spurs. None of these things will do the cell phone user any favors.
    This has to be one of the most insidiously stupid ideas I’ve ever seen. What makes it insidious is that it sorta works, so you can’t fault the physics. However, in the real world, all that is happening is the recovery of a minute amount of the energy expended in transmitting. Since this is at the milliwatt level, one can expect microwatts potentially recovered, most of which would then be lost due to the inefficiencies in the process of boosting the µV (that’s microvolts, not ultraviolet) level signal up to 5V. So in the end, what is saved? A few picowatts maybe?
    Ridiculous. Absolutely ridiculous.

    1. Eh.. It does not ‘work’ as claimed.. Its a scam – go with your gut.,. We know these are fake products designed and marketed by scam artists. There isnt any splitting hairs – The people perpetrating this nonsense via crowdfunding know EXACTLY what they are doing.

      That maxim about never assuming malice when incompetence suffices is totally wrong. In our society always assume malice – even assume incompetent malice – but surely its obvious what these scam artist thieve charlatans are doing – and techCrunch and KickStarter are joining them.

      All of them are scam artists at least part of the time.

      Marx would call this late state capitalism – I just call it scam artistry and a gullible, infantile population.

      1. When I said “sorta works”, I wasn’t implying that the device worked as claimed, rather that it is actually possible to derive energy from ambient rf. It is neither practical nor efficient, but it is possible.

        1. It is practical for some things – but they are special use cases… I know what you meant – I just urge cynicism on things like this.

          It is one of the disheartening outcomes of internet proliferation – a large pool of saps for scam artists. It is important not to give the benefit of the doubt to companies and individuals promoting free energy scams. It is the close cousin of cancer-cure scams, gas mileage device scams, and all manner of pseudo-medical quackery…

          You know all this though..What you maybe havent investigated enough to see the patterns, or were not considering is the type of people and organizations that take part in these scams. They are extremely cynical criminals – making false claims, and skirting legality – while preying on innocent people.

      1. “literally sucking up all the rf energy”… Huh?
        You can’t “suck rf” any more than you can suck light (which happens to be rf at a much higher frequency than what we normally consider “radio”).
        It can block or shadow the antenna, but it cannot suck anything.

    2. I had a friend who was utterly convinced that putting a magnifying glass between the flashlight and the solar cell would make an unlimited free energy power generator. Rather than try it like I suggested, he just continued droning on about “the man” keeping us down.

      1. This project is the equivelant of your friend trying to crowdfund that idea of his….In other words, not ‘incompetence’ – but actual malice – a desire to take $ on claims that have not been tested (because they would fall apart).

        its a topic that cuts to the core of the sickness at the center of our society: misdirected liars greed getting a pass if it generates cash.

      2. I had the same idea, a room full of solar panels powering a light bulb in the middle. If you needed more power, add more panels! I was 8 years old at the time.

        I had another about a series of magnifying glasses making a deadly solar cannon, but I was 10 by then.

    1. It is very likely.. They can claim this phone case is a green product – and ‘reduces your carbon footprint’.. .They can claim anything they want – their product defies physics and is surrounded by hyperbolic claims.

  7. Proving, without any leeway or wiggle room: TechCrunch judges are ignorant of basic science, ignorant of how to spot a scam, ignorant of how to avoid promoting a scam, and themselves may be scam artists – or willing if not eager to partner with obvious scam artists..

    This case will easily be as effective as the ‘sticker antenna’ products….

    1. At this point anything alluding to Tesla, possibly including the car maker, is a sure sign that you are dealing with a scam artist. Some assholes tried to crowd fund building ‘Tesla Towers’ to ‘broadcast free energy’… They got over 100K if I am not mistaken..

      Shades or Solar Roadways…

  8. We have come to the point where everyone can graduate from the university level program those days … I guess that the version 2.0 of this ‘magnificent invention’ will reuse heat of the discharging battery to spin the miniature turbine which will then charge the battery back …

    1. Yeah, but heat is wasted energy, if you could harvest it that would be good. RF energy is not wasted, but useful energy, if you harvest it you’re “stealing” signal from your phone. Forcing it to increase transmit power, turning this “charger” to discharger.

  9. TL;DR: I agree that this project is nuts, but strictly speaking it’s not running into problems with conservation of energy.

    From a basic physics standpoint this project isn’t impossibly stupid, it’s in the details where it has problems.

    Any accelerating charges radiate energy as electromagnetic waves, and this includes the charges involved in any current in the device, so (more or less) every part of the circuit is radiating energy (this is known as Van Eck Radiation if you want a search term). In principle one could imagine capturing this energy and doing something with it without interfering with the radiation associated with data transmission. This would allow them to do precisely what they claim to do with out any conservation of energy problems.

    The real problems with what they are trying to do are:
    1. The total Van Eck radiation power is likely to be so small it’s not worth bothering with.
    2. Capturing a significant fraction of the Van Eck radiation power without significantly disrupting transmission/reception characteristics is likely to be extremely difficult from an engineering standpoint.

    1. Agreed, there’s no breaking of physics here. They aren’t claiming over unity, or perpetual energy. They are simply selling you a product that converts your battery to heat.

    2. I disagree -they make a claim that i specific; this device noticably improved battery life – will ‘improve’ battery life measurably’ – however, that claim requires physical laws to be modified, or null..

      They dont claim thy can manage to help you regain pico and micro amps per hour – they make broad claims – which would require different physics than we have.

      Therefor they are both scam artists, and pushing bunk-physics through implication.

    3. “In principle one could imagine capturing this energy and doing something with it without interfering with the radiation associated with data transmission.”

      Not with a device that’s this close to the phone. It’s violently in the near field, which means it affects the transmitter as well. Even if you try to capture unintentional EMI (what you’re calling van Eck radiation), you’re so near field that you’d be potentially screwing up the actual digital logic in the phone.

      But more important than any of this is what you say as point #1: the total power in all of that is so pathetically small that this is total garbage. They’d be better off claiming they can extend battery life in the winter using a Peltier junction in reverse: if I had to guess, the numbers would probably work out better.

  10. Switching to Airplane mode will give you a boost in battery life. This will do nothing but yse up the battery faster. Most snartphones can output between 350mW and 500mW power at the antenna. But you want much lower output if ypu expect to get any decent battery life. Even today, the cellular radio is the most power hungry part of your phone other than the screen, and it’s not that efficient. Maybe you’ll see 40-50%;PA efficiency with HPSA, maybe as high as 70% with SC-FDMA in LTE. Of course, that radio’s powered by a switching supply running from the 3.6V Li-poly battery in your phone, so there’s maybe 90% efficiency there. Then there’s the back conversion form captured RF to +5V, and another converter from +5V to the charging voltage. So overall, you’re lucky to see 25% efficiency through the system.

    But that’s not the end. The capuring device is attenuating both transmit and receive power, causing the cell tower to instruct it to increase transmit power. So now we’re boosting output, likely getting into a less efficient operating point. Plus, with all this RF bouncing around in the case, you’re delivering a noisier signal, demanding even more power. The switching supply is working harder to provide the needed current, dropping that efficiency level. And by now, the battery is heating up, losing even more power to heat.

    This is stupid… it’s going to drain the battery faster than not using it.

  11. I can plug a USB OTG cable into my phone’s USB port, then plug a USB charageable battery pack into that and take power *from* the phone.

    Completely useless, unless one can sneakily vampire juice from someone else’s phone…

  12. Went and read more about it – apparently one of the co-founders is a chair of engineering at Ohio State.. Apparently he feels its ethical to take part in free energy scams.

    Supposedly the ‘technology’ being used to harvest energy is licensed from university of ohio – but this itself is a meaningles claim, since the tech. involved can be a simple wire coil – or a very complex substrate born filter – but both will fail at the goal of generating energy actualyl useful to a smartphone.

    Smartphone draws 1-3amps… This device can maybe harvest 5mw…. .1amps – but i doubt even that much… I would imagine this “recovering” maybe 1-2mw when the phone is on and broadcasting – consuming dozens of watts.

  13. This is pretty assuredly a scam, or at best a product designed in good faith by people with a tragically poor understanding of the physics involved.

    Here’s a thought, though: what if the network of antennas in the case could actively detect the angle of the strongest incoming signal (i.e. the best path to the cell tower), then selectively (likely using metamaterials that don’t exist yet) turn on radio-absorption in the areas that the radiated energy wasn’t useful? Only the necessary radiation would escape, and any energy that was going to be absorbed by a wall would instead get recycled (at some abysmal level of efficiency) back into the battery.

    Basically you’d be giving the phone a sort of kludged-on phased array. Obviously a better solution would be to build the phased array into the phone antenna itself so that you could focus and limit the transmit power instead of wasting and then trying to recapture it. I know that some routers with multiple antennas can do this to a limited extent already — maybe it’s only a matter of time before it’s seen in phones?

    1. The energy you’d be absorbing, from the cell transmitter, would be utterly utterly minute. You’d be better off with some sort of MEMS movement-harvesting generator. Or a solar panel on the back of the case. Or just plugging it in the charger 15 milliseconds sooner.

      Phased array antennas might be good though. It’d also cut down on interference, maybe allowing more phones in a cell, or cells to be closer together. More efficient use of bandwidth, anyway. Might be possible, increasing CPU power will help.

  14. Laws of thermodynamics come to mind…
    Entropy in particular…
    If people subscribe to this then they deserve to be burnt…

    Napervillian aka kcim


    1. What, you think everyone has been studying thermodynamics? You think everyone knows what entropy even means? Come on, they just don’t know any better, and people who know, including kickstarter, should protect them from scams like this.

      I think you deserve to get bitch slapped for saying someone deserves to get burned.

      1. Hello,
        First I am just a laymen, so if I can see that this is unworkable, what excuse do others have that this is a scam?
        Now I’ll agree with you that Kickstarter should vet out the (project) posts better.
        Are you going to count on that, before you lay your money down?
        Now I am not a physics guy but know enough to look it up before posting…


      2. I remember entropy, enthalpy, and the laws of thermodynamics from middle school. People with a 6th grade education SHOULD know better.

        Burning is a bit overkill, however — it is a waste of good oxygen.

  15. To me this seems like something that recovers energy that would go to waste. Similar to the use of regenerative braking in electric vehicles. RF energy from a phone isn’t like a laser where 100% of the energy is beamed in a direct way. Instead it spreads out everywhere and only some of it reaches the phone tower. Maybe recovering some of that energy isn’t a bad idea.

    1. Regenerative braking works because cars are huge stores of kinetic energy – and slowing them generates a lot of heat(power). Electromagnetic generation works in this instance to reclaim a truly substantial amount of otherwise truly lost power.

      This, on the other hand, relies on low-efficiency inductive coupling of a signal meant for broadcasting, not pilfering mv/ma with a coil.

      The real issue is their claims vs. the potential of their device to be beneficial to owners. They claim it will be practical and improve phone battery – but there is reason to think it will actually slightly degrade phone performance and have no measurable impact on the actual phone battery performance in a real users phone under normal use.

      That makes it a scam. As such, the people pushing it become scam artists – from the founders to techcrunch. That is how responsibility works in a society based on justice.

  16. Is this really trying to generate energy? Or is it just trying to recover wasted energy? Similar to how electric vehicles use regenerative braking. RF radiation isn’t a laser beam but it spreads out everywhere with a small portion reaching the tower.

    1. If the case had a way of figuring out which direction it was to the nearest tower, and then if it had a way of only absorbing energy on the side of the phone opposite that, then maybe, but neither of those are true.

      But if you have the info needed to make the signal directional and pointed only toward the tower, it’s better to direct and reflect the RF toward the tower, rather than capturing some of it, rectifying it, sending it back to the transmitter’s input power supply, so that it may be turned right back into RF, with each step being terribly inefficient.

      A typical directional antenna, such as a log periodic, Yagi, or satellite dish, works by taking a dipole antenna and surrounding it with passive directors and reflectors to aim the energy from the antenna in one direction. That does work, without violating physics. It’s also a whole lot more efficient than capturing some of the RF, rectifying it, and passing it into the power supply of the transmitter to let the transmitter turn the energy back to RF.

      But the big reason cell phones use omnidirectional antennas is that we don’t know in advance where the cell tower is going to be relative to the orientation of the phone. If this device absorbs any of the signal, it’s harming the phone’s performance.

  17. Cell phone part has variable power so that it transmits the minimum amount. But since it tries to irradiate in all directions, if your absorbing thing is in the opposite side of the antenna it will not increase power and the device will actually harvest some. I would also assume that since the smartphones are kept at 45ish deg inclination when using for smart things, most of the energy beamed towards the ground is useless and will be absorbed by thins thingy and fed back. So it could work….. the problem there is that they claim it absorbs 90%…which is kind of bad.
    Another way it could work: BT and WIFI don’t really adjust power as required, so probably many times they transmit too high, which could make sense of this device to absorb.

    But clearly, since the thing absorbs part of what you are transmitting there will be situations when your phone will not work as desired, because the 10% left is not enough for proper communication.

    So I will pass, will just wait here for smart directional antennas with super cool beamforming in phones.

    1. “But since it tries to irradiate in all directions, if your absorbing thing is in the opposite side of the antenna”

      Your cell phone is what, 0.5″ thick? At most? At ~2 GHz, the wavelength is what, 15 cm? The absorbing thing isn’t on the “opposite side” of the antenna as far as the radiator is concerned. It’s on top of it. It can’t tell the difference – it’s too close.

      You can’t put stuff that close to an antenna and not expect it to violently change the transmission characteristics. It’s in the near field.

  18. Why do they need a kickstarter?

    Why not fund their project by paying themselves their own money?

    The excess cash generated as they move money from their right pocket to their left pocket should be more than enough to fund their project.

    Hell, if you repeat it enough times, we’ll all be millionaires.

    1. They are trying to get bankers (who rely on the scam you allude to) to get on board with their scam.

      They want more scam artists to help them scam more innocent people.

      Truth is ugly on this one,. and those pushing it.

  19. I’m just going to say, I really don’t understand why everyone thinks this is bad idea. I haven’t seen the device so I’m not going to comment on it, but rather the concept, and the physics. Having a receiving antenna that translates the RF energy into electrical/chemical energy isn’t a bad idea. I only use the transmission part of my cell phone probably less than 10% of the day, so being able to capture all the energy of other people’s transmissions, and other RF I think is just smart. My question is though, how much am I really getting back? I doubt much of anything. AM/FM and UHF, etc would be by far the highest wattage transmitters, but typically they’re only about .5 watts in most areas I’m located. So in reality even if I converted that to electrical/chemical energy, I bet I’d get 60-70% of that, meaning at best .35 watts. Now it takes 2 hours to recharge my phone at 5 watts, so if I assume linear proportion, then it would take roughly 15 hours to recharge my phone, ands that’s if its off. I would be curious how much wattage my phone uses in just standby. Another problem I could foresee is the reception distance, and incoming calls/texts. At certain distances would the harvesting of RF, prevent calls and texts from being received? I would guess so. How would one prevent the device from harvesting during calls and texts, in other words during transmission? I don’t know, maybe some type of electro-perm magnet. It would be interesting to see those tests and results, or at least some specs to perform some good ol’ mathematics.

    Now if this is harvesting from the transmission of the phone, whoever believes this is super dumb, or super ignorant. Here a very simple breakdown. The typical cell phone transmit 1watt, so if the harvesting was 20%, then the phone would be transmitting .8 watts, and the device is absorbing .2 watts, but since the power is coming from the phone, and the absorbed energy is going back to the battery, its a closed loop system. Therefore the energy loss between the transmission, absorption, and conversion ultimately means your just expending power for no reason. If you want to save battery, just change the transmission power? If you lowered the transmission power to .8 watts, it would last longer than the device and its doohickoy.

    1. The problem is background RF energy is insignificantly small. For example, the biggest radio station in my area transmits at 100,000 watts. But that energy dissipates in a sphere from the transmitter. Let’s say you were only one mile from the transmitter and your antenna was a generous 5 square inches of metal facing the tower. Your fraction of that sphere is only 9.9×10-6 watts. Yes you can harvest the power, but not enough to matter in this application.

  20. This is actually a really, really clever move on the part of the Nikola Labs guys.

    They know that Qi and inductive charging is coming as a mainstream feature in the next wave of phones. So they are just getting out ahead of that, before anyone can see the landscape, before the commoner technology consumers have seen anything else.

    They probably have had *exactly* that conversation, at some point: This technology is fundamentally flawed, but now is the time to do it, and everyone will be amazed with us.

  21. Here is a cheaper/easier way of doing this.
    !. Open Phone
    2. Solder Germanium Diode to Antenna
    3. Solder Cathode of Diode to Capacitor
    4. Solder opposite end of Capacitor to ground
    5. Solder Diode/ Capacitor Junction to Battery.
    6. Done

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