Wireless Power: Myth or Reality?

of energy going into today. We sure do. I tell you there's nothing like a live show to get you pumped up for two hours of podcast recordings. Really, someone kill me. So you're rethinking, then, huh, I'm always rethinking. Okay then okay. So, but yes, we were talking about energy. Well that that kind of leads into our topic for today. We wanted to talk a little bit about wireless power and whether or not it's actually possible and it is. Okay, So I hope you enjoyed this week's episode of We're

going to go into a little more detail than that. Now, wireless power. This is not a new idea by any stretch of the imagination. It actually dates back almost as far back as a as as the transmission of electricity itself years ago. More than that, going a little further back. All right, so you're you're going to talk about our buddy, aren't you. We are we are going to talk about your friend and mine, Nicola Tesla, who is apparently number nine on the top ten. He is number nine on

top ten inventors of all time. That this is an inside joke that no one outside of like five people are going to get. But that's okay. So Nicola Tesla Tesla was the father of the alternating current. Yes, and in fact, Tesla invented many things. I was a brilliant, brilliant man whom kind of suffered a little bit of a breakdown in his final years, actually eyed penniless despite the fact that he invented alternating current. In fact, um

he had a famous rivalry with Thomas Edison. Uh Thomas Tessa, of course, the inventor of direct current and um and Tesla actually managed to land a lucrative deal. Um in a way, he landed the chance to provide electricity to the World's Fair in Chicago. That was a big deal. I mean, of course, that the entire world's attention was directed on this city and m so Tesla very well. Uh, he's famous for for a lot of things involving electricity

for a good reason. But one of the things he's also famous for is something that still comes up in debate in scientific circles as to whether or not he was brilliant or crazy. And this was the idea of broadcasting electricity. Yeah, that's uh, that's saying seems a little weird, especially in our very very wired world. I mean, you know, we think wireless. You're thinking you know, Bluetooth deo ways

where you know WiFi? Yeah, maybe a little Marconi style you know, over the air FM, yeah, something like that. You know electricity, Yeah, you don't necessarily think electricity. If you're thinking over the air electricity, you're thinking lightning. Right. But you may have heard of these devices known as Tesla coils, which can put off quite a bit of electricity, some high voltage electricity, and can even be used as musical instruments. Yes, architect does a great act with Tesla

coils from creating music. But don't get in the way. No, unless you're in a fair day cage, stay far away from the Tesla coils because they could kill you. Um So, yeah, it's for the well grounded audience. Yeah. But but one of the things that Tesla tried to create was he did this project in Colorado is warden Cliff was the

name of the project. It was an enormous Tesla coil tower, and the idea here was that he was going to use the resonance of the earth to broadcast power um throughout the atmosphere and this would eliminate need for infrastructure like cables and wires um. It never really worked. The part of the problem is that he ran out of

money midway through the project. His investors pulled out when they thought that he was being Depending on who you asked, some people say they pulled out because they thought he

was crazy. Other people say that that they pulled out because they were worried that it was going to affect um other financial um UH endeavors down the line, the idea being that there will be no way to monetize this because Tesla would have found a way to provide energy essentially for free, and that did not make people happy. Who you know, depended upon energy UH as a means of making money. So depending on who you asked, they either thought he was crazy or they thought he was gonna.

They were going to bankrupt him, and they pulled out and he was unable to finish his project. There were reports that he had supposedly been able to um too light several light bulbs that were twenty six miles away from his tower, but that's unsubstantiated at any rate. Tesla kind of comes up with this idea about broadcasting power, never really comes to fruition, he dies penniless, and then, uh, no one's really able to necessarily replicate the Tesla's ideas.

He didn't leave very good notes, so it makes it very difficult to try and figure out exactly how he was designing this and whether or not it would work for real zies. Yeah, it's yeah. Actually, that's one of the things that makes him so much fun to, uh, to study, is that he is so enigmatic and you know, hard to duplicate the experiments and just that whole you know Tesla mystique plus it's you know, electricity seriously, and and he did have he did have some very well

documented quirks. He was he did have some signs of obsessive compulsive disorder. He was frequently washing his hands and he didn't to touch other people. And um, he also reportedly suffered from hallucinations, very vivid hallucinations throughout his life. And um, so there are other elements to his psyche that that bring into question, you know, how how sane his ideas were towards the end of his life. However, we we now skip ahead and wireless power is a reality. Um,

there's with limitations. What's funny because people, um, this was all the rage at c S a couple of years ago. Um, you know, talking about this new way of charging up your cell phone or your iPod by laying it down on a on a mat instead of plugging it into the wall. And everybody was talking about how cool this idea was. And it is cool, absolutely cool at least in my opinion. Um, because you don't have to mess with your your wiring and and finding the right adapter.

You could just lay it down and it's charged. But uh, you know it's funny because snagging it and knocking the phone off the counter. Yeah, only the cat, you know, knocking the cat off the counter. Oh, the cat knocking the phone off the counter. I gotta know. So anyway, actually I suppose you would. I mean, if it's not tethered to anything, then it's going to hit the floor at least, but dangling anyway, you're not gonna get caught

on the cord anyway. With the Tesla thing, you know, the whole putting it that totally puts it into contact. You go, wait a minute, if you could, if he was experimenting with this long ago, you know, maybe this isn't such a new thing. But there are different ways

to to transfer power this way. I mean, it is possible to do, especially over short distances, but it sort of depends on what you want to charge and how you're going to do it, and how much electricity you actually need to to ferry over from one side of the other. Right, this isn't the same thing as as broadcasting enough electricity to power your home. This is talking about very small uh distances. Actually, usually it's a contact thing.

It's wireless, but but to two different elements are normally in contact with one another, although not always, not always, no, we'll get to that, but them. A common example is if you have an electric toothbrush that you would put into a little cradle and that's what allows it to charge, and it doesn't plug in. It's you know, the cradle is smooth, and the bottom of the toothbrush is smooth, and you just stand it on the in the cradle and and it charges seemingly by magic, but it's not magic.

There are no lebri cons involved. It's simply um, no elves, no electromagnets, that's the only no elves. But electromagnets are involved. So it charges through a process called induction. And uh, it all depends on electro magnets. We talked about electromagnets not that long ago, when we were talking about e MPs. That's true, that's true. Um. Basically, an electromagnet is a piece of iron wrapped with many many many times with

a coil of copper wiring. Basic form of an electromagnet. Yeah, when you run a charge to it, it becomes an inductor and creates a magnetic field around there. Right, So if you were to take a nail and you were to wrap a copper wire around it several times and then connect either end of the copper to a battery, you would create a magnetic shield and you could pick

up iron filings that way. Pretty much. Anyone in a in a physics class or or you know, even elementary school has done this sort of thing before, but it has many many other applications in the real world. Of course. Um, you've probably seen the videos of the Junkyard where you've got the giant electromagnet that you know, picks up a car and moves it from one stack to the to

another or into the car crusher or whatever. Um. Probably virtually one third of all cop chase scenes in the city and in somebody driving into the thing and getting their car picked up the other the other two thirds usually a pool. So um, but yeah, so and and um, yeah you're I'm kidding, but you know that that's the famous scene. And that's an electric bagnet that people will

be familiar with. Also, they're uh, they're used in the little sections under the roadway when you pull up to a stoplight, they detect car using a similar mechanism, right, And so you can use electricity to create a magnetic field. What you might not know is you can also use a magnetic field to create electricity. And that's that's the basis of this inductor, this wireless charging um technology that we're talking about right now. So within the cradle, that's

the part that plugs into the wall. So you're drawing electricity from your your your wall. Uh, that is sending electrons through an electro magnet in the cradle. When you put the toothbrush in there, the toothbrush and it's base has another essentially another coil inside of it. The magnetic field will induce electricity within that coil and charge the

battery inside the toothbrush. Same thing for the cell phones things of that nature, where it's using basic it's based off the same technology where you're using this magnetic field to induce electricity and that in turn charges a battery. That seems very simple. It's it's actually a pretty simple concept. It's it's difficult to explain without graphics, so it's a little difficult to talk about it without you know, looking

at something. But it's nice of you to hold up the drawing to the microphone so everybody listening can see it. I hope you all appreciated that. It was you know, I I even actually I have a whole three D model here here, look at this and this over here. Yeah, and that totally makes sense to me, I know, it doesn't it It's so clear. So yeah, that's that's the

main way we use wireless power right now. But there are other ways that people are working on that use a similar technology, but it's meant to transmit power in a larger area. UM. So, for example, some guys that in my t are working on this this coil that has capacitors at the end of UH. It's think of it like a think of a circle where you have one arc of the circle cut out, Okay, so it's not a complete circle. On either end of the that arc, there's a little capacitor and then you have the coil

wrapped around it. And the idea here is that by creating an by running electricity through one of these, you create a magnetic field, and if you have another UM device that another arc that resonates at that same frequency, you can broadcast electricity in a greater areas because it's depending upon not just the magnetic field but resonance. So if you if you can get the two objects to reson excuse me, to resonate at the same frequency, UM,

you can broadcast power. Yeah, basically, it's that that's sort of UH. I think if you're if I'm understanding you correctly, you're talking about radio charging and that's and that does have to that does mean that they have to match up and that actually are Managing editor Julie sent us an article not too long ago about that very thing. UM. Nokia is working on a technology in one of their

United Kingdom offices UM. According to The Guardian, UH, this technology would basically use frequencies five mega hurts to ten gigger hurts, which is the same basically as UH area of which you'd find UM wireless land, bluetooth, mobile phones, microwave ovens, UM and UH. It would convert electromagnetic energy into electric electrical energy. UM right now can handle about

five milliwatts. They're trying to get twenty, but fifty would be really powerful enough to recharge a cell phone battery and then thereby you wouldn't even need to worry about plugging in your phone or finding an induction pad on which to place your phone when you get home. Yeah, so you can with one of these systems if you if you were to perfect it, you could have a single UM powered coil that provides enough of a magnetic field to charge multiple objects all at the same time.

So you would you could have like a room in your house which was the charging room. You know, you just leave your camera on your phone and MP three player or whatever and there, and then they charge just based upon the power being drawn by that one uh that one coil. So it's a pretty cool idea. And it's not the only way that we can do wireless power. There's another way which involves microwaves. Oh yeah, you can beam microwaves at a rectifying antenna or a rectanna if

you prefer. It's not a joke. It really is a rectanna. I'm not treating it as a joke. It's just funny to me how people like to combine words and make new ones. Yes, it's it's it's catching. Is this you know, it's every Every business has to have its own jargon.

So uh yeah, if you rectanna can can accept incoming microwaves converted into electricity, and this could become very useful if we can perfect a way of gathering energy in outer space to beam down to the Earth, because when you think about it, a lot of people would imagine the Earth as a closed system. You're getting only so much energy out of the environment, but it's not really closed system because you've got sunlight coming in all the time.

But beyond that, if you were able to create say a satellite that had solar cells on it and could collect sunlight without the the interference of atmosphere and then beam that energy some way down to the Earth. You would suddenly have a very uh useful form of um, you know, an ending energy. Now, there are some problems with it. I mean, obviously you have to create a device that can beam a microwave beam at a very specific location. You have to have the antenna there to

pick up the beam. Some people are worried about the idea of microwaves hitting the Earth all the time. There was a discussion of possibly putting an entire solar farm on the surface of the Moon, but of course the Moon is not always facing the same part of the

Earth all the time. So in order to get the beam to the right set uh antenna, I suppose either you could build a series of antenna's or you would have to have some sort of reflective satellite network so that the beam hits a satellite and that in turn beams it to another satellite until you have a direct line of sight on the proper antenna, and then you could beam the energy down to Earth. So it's not

obviously it's not the most perfect system. Also, another problem is that if anything were to happen to the solar panels on the Moon, you'd have to have some way to fix them. So there's a good chance that you would need either some sort of really advanced robot or more likely some sort of lunar base in order to maintain the solar panel farm. Um. Otherwise, you know, something goes wrong and then suddenly you're you're perfect source of

energy is no longer so perfect. Yeah, but it's funny because you talk about things like can we convert electromagnetic spectrum into electrical energy? Well, you know, light from the Sun carries quite a bit of electromagnetic energy, and we use solar panels to do just that. Yeah, they're not terribly don't think about that as being but that's it's kind of the ultimate and wireless power because you think about all the plants that use the Sun's energy. I mean,

that's wireless power. But uh, yeah, solar panels are not the biggest problem we have with solar panels right now is that they're not as efficient as we need them to be in order to to really get the most out of them. That I think the efficiency is down in the like the the teens are the twenties maybe, so that's pretty low. That means that you're losing eight of the energy that you could be harvesting if the

technology were perfect. But it has increased significantly in the past a few years because we've done so much more research on it. Yeah, and of course the push towards green technology over the last few years has has, you know, spurred on even more research and development as companies see a way of possibly making a profit off of this. I mean, you've got people who are willing to pay two make make their lives more green and environmentally friendly.

And once you start making sure that the whole process is economically viable, than usually the research and development quickly follows behind. You know, I wonder if it's to be cynical, But yeah, I wonder if the market for UH copper stolen from street lights it's going to drop if we switch to all inductive and all resonant and all radio. I'm sure there will always be a market for jewelry that will turn your arm green. I I you know,

you really are cynical. I'm just saying I've I've got some nice jewelry that turns my skin Green, it's not as nice as it could be. I guess we'll see if I ever give you a penny for your thoughts. So thought Green talking about the the microwave transmission again, just really quickly. One of the neatest um potential uses I've seen for this technology is for a an airplane that would never land. That reminds me, but they might be giants song. Well, this would be an unmanned vehicle.

I was wondering, what you're gonna do, you know, an unmanned drone. But it would it would convert. It would have a rectana on the on the plane itself, and you would be microwaves to the plane and that would give it enough energy for it to maintain its flight. And if you were to have enough you know, devices here to be microwaves to it, it could fly indefinitely. Alright, So do you have anything else on wireless power today? No? But I do have something else you do? Yeah, I

have a little a listener mail. This listener mail comes from Sergio. Sergio says folks. He said that Linux is a derivative of Unix, but Linux is a recursive acronym that stands for Linux is not Unix, just like Canoe, which stands for a canoe is not Unix. Linux may look and feel like Unix, but it is not Unix. It was mostly written from scratch, and the Colonel probably shares little if no code with a T and T Unix. This is all about patent copyrights and being free slash

open source regards. Sergio. Sergio, we totally understand where you're coming from, and and we're not arguing that. What what we were trying to get at is that Unix spawned the or we should say Unix inspired Minics, right, which was a project that a college professor created to create an open source UM operating system that people could fiddle with the code, and then Torvalds saw Menics and that

took from that the inspiration to create uh linux. So you well, it's not a direct derivative of Unix Unix inspired Menics, which in turn inspired linux UM. We were kind of using shorthand in that particular episode and possibly in the process made it less accurate than than it needed to be. At the time, though, we were worried about getting too technical and losing all the people who

had never heard of Linux to start with. But thank you for writing and keeping us on us definitely, and a couple of other people made the same sort of point, and uh we we heard all of you. Um I just read Sergios because it was a good representative email. So if you guys have any comments, you would like to make, any questions or suggestions, criticisms that sort of thing, you can write us. Our email address is tech stuff

at how stuff works dot com. You can read all about wireless power at how stuff works dot com, along with hundreds of other topics, and we will talk to you again really soon for moralness and thousands of other topics. Does it how stuff works dot com And be sure to check out the new tech stuff blog now on the house stuff works homepage, brought to you by the reinvented two thousand twelve camera. It's ready, are you