CES may be over, but in our post-technalia hangover we're still discovering a few small wonders that flew under the radar last week, not least of which is this RCA Airnergy, a small USB device that harvests electrical power from Wi-Fi signals. Anytime the device is in the vicinity of one or more Wi-Fi sources, the Airnergy is charging, converting the wireless antenna signal into DC current that can power myriad small electronics. The idea isn't novel, but this is the first time anyone has created a commercial product efficient enough to be useful.
The Airnergy unit stores the charge in an internal lithium battery, so you don't necessarily have to be in a hotspot to recharge, say, your phone. If you have Wi-Fi at home, the Airnergy will automatically charge itself anytime it comes in range of your wireless hub (a good overnight charge should top off the battery; recharge time correlates to its proximity to the Wi-Fi source). You can then tap into that stored charge later when your iPod dies on the subway or your phone starts flagging during an important call.
Now, the limitations: the Airnergy unit that should hit store shelves this year (for about $40) is expected to have a USB connection, meaning it won't sync with a lot of devices (like the iPod or iPhone) without some kind of connection converter. It's also an extra device that you have to carry around with you, making it a cumbersome addition your daily tech routine.
But we're big-picture thinkers here at PopSci, and here's what you need to know: RCA is also developing Wi-Fi harvesting batteries that should cost roughly the same as the OEM batteries in most devices; that means your phone/iPod/Blackberry/etc. will be able to recharge itself wirelessly anytime you're near a hotspot without any extra peripheral devices. As cities and networks experiment more and more with Wi-Fi clouds that blanket entire cities, the day may not be too far away when our smartphones download our email, update our Twitter pages and recharge our batteries all from the same signal, all the time, no matter where we go. That's a brave new world that can't get here soon enough.
The thought of wireless energy is mind boggling. I thinkg we should seriously consider the possibility of wirelessly charging electric cars. That would deal with the long distance travel in cars that currently can only travel 40-60 miles.
if that can charge my ipod even once from the internal backup that would be an amazing bargain.
i can see them crediting tesla as a profit for these things.
This isn't real it breaks the laws of physics. It is simply not possible.
Wow... this seriously blew my mind. I may be wrong, but this sounds like somewhat of a first step to wireless power. If I can charge my phone, my ipod, and whatever else I may be carrying around wirelessly, then how long will it take before I can charge larger, more power hungry items?
Look up pharanguga, the math is there. You can not gather that kind of energy because you can not collect all the energy available the wifi signal travels out in a sphere while the device can only gather the energy that hits the antenna. Think Critically.
This is real. Tesla designed the technology a hundred years ago. The product wouldn't be for sale if it didn't work. Think logicaly.
Will it take longer to charge if there are a few Airnergy devices next to the WIFI spot? Will it decrease the signal overall strength?
Sounds cool, but doesn't this highlight a concern about electro magnetic fields being a health hazards? If sitting in a Starbucks can charge my battery—what's it doing to my body?
Cool as it sounds, this product cannot operate the way it has been described. While there are a few 'wireless power' examples that use 100W induction currents, the power output of a WiFi access point is a tenth of a watt or so. Assuming 100% efficiency and absorption at 5 feet away from a 100mW home router (reasonable figures) it would take 34.5 years to charge a phone battery.
I would like for this device to be real, but.... c'mon.
Nope, my laptop (which has a fairly good antenna, 17in screen) reports that the signal from my average router is about -60dbm which equals 1 nanowatt. My phone has a 3 watthour battery, assuming a perfect charge (not possible) it would take 3,000,000,000 hours or 342,238.66 years
Not critiquing anybody's math, but since RCA is making this claim, I suspect that it will work -- to some extent. Note the mention that it will work better if you are near to the wifi source.
I do doubt that it it will be a real mind blower, but it may occasionally extend the life of your phone batt. Phones use amazingly small amounts of power for what they do.
Obtaining minute amounts of power from RF is nothing new -- years ago there was an article on building an FM radio powered by an AM signal. The AM section used a simple diode detector. A crystal radio can drive headsets, and that's how much energy it produced. The wifi setup is probably somewhere in that ballpark. ( Forget the electric car!)
For you Tesla freaks, Tesla was a genius, but the famous Tesla coil is not really any sort of practical wireless energy device. Huge models have been built which produced huge electrostatic discharges. They could also be used for parlor tricks like lighting flurescent bulbs, but they're really not at all efficient.
for all the gullible out there this is copied from Pharyngula
Here's some math. Long story short, by my calculations, 100% efficiency and absorption at 5 feet away from a 100mW home router, (reasonable figures), it would take 34.5 years to charge that blackberry battery.
It's not a Dyson Sphere, so you only get the power that hits the antenna. Surface of a sphere = 4pir^2, r = 60" (5 feet). Surface area of a 5' sphere = 45,216 square inches.
The device appears about 2" x 3" = 6 square inches. The device then picks up, best case, 0.000133 of the power out from the router, which is 100mW, so.. 0.0133mW
If you leave it there for 24 hours, 0.0318 mWh are stored. According to Will's battery, it has ~4,000 mWh capacity.
So, it would take 12,579 days, or 34.5 years, to charge your blackberry battery once, presuming 100% absorption, no losses.
I call BS. Even adding up all the laptops, cell phones, routers, portable phones, everything, all the noise in the RF spectrum that could hit that device, I don't see it charging the internal battery even in a week.
So if anyone out there wishes to waste money please send it my way and i will send you a used battery that will be just as useful
It sounds cool. For backup power you need a just a Wi-Fi signal. If you want it to work better you could also charge it first with a charger.
Free energy. Good arguments can sell anything.
I just wonder what makes this so much better than a similar battery box covered with photovoltaics? Works in the dark?
To all the people here commenting on how the technology is impossible and mathematics and blah blah blah. Apparently you are very very wrong. RCA is a large name brand company and showed this device at the CES. They charged a blackberry from 30% to full in 90 minutes using nothing but ambient wifi energy as power sources. Sooo... By my calculations. That makes you wrong. Check your math again I suppose.
If you live somewhere like NYC where there is wifi basically everywhere. From apartments to coffee shops. That little device will be constantly charging itself. In a pinch, like a dead cell phone battery, the device will do what it's supposed to do.
I doubt it was designed to be the only method of charging your phone or Ipod. But it was designed to provide emergency charges.
If your so smart bgtony08 then do the maths and show how it is possible
You clearly are a salesman's dream customer who believes anything the salesman tells him, So Come on prove us wrong with the numbers!
Suppose these things actually do work. Suppose a bunch of people buy them. Wouldn't they cause a lot of interference and blockage for people who are trying to use the WiFi signal for communication? WiFi is designed to transmit data, not provide power. I agree with Someboy, you would probably get more power from a photovoltaic cell of the same size.
This isn't a matter of poor math. But simply a magician's trick. By charging a device in X minutes, they only proved what the battery can do, not what the collection device itself will do. This is the same bait and switch the "solar chargers" do. They charge the battery off the mains before the show and then run the demo from the battery. We go gee-wiz at the dog and pony, whilst the reality is, putting batteries in the sun gets them hot and wears them out. But if want to go Mr Wizard on us, might I point out RF energy works on inverse squares. I.E. by halving the distance, you increase the energy by a factor of 10. That means you won't get much from your neighbor, but the closer you get it to your router, the better.
wow, did you just *seriously* say that solar power doesn't work?
What next, are you going to suggest that all this 'internet' stuff is just smoke & mirrors because it's impossible to make a signal travel that far?!
Oh, and I know I'm probably an illusion, but inverse square means if you half the distance you increase something by a factor of *4* ... i.e 2 raised to the power of 2...Gee whizz Mr Wizzard, seems that's not 10.
Um... the inverse square law means that the power drops off rapidly as you get farther from the source. It's well documented, for example: en.wikipedia.org/wiki/Inverse-square_law
Solar chargers actually =do= provide usable power, and a battery case covered in photo voltaic cells would perform far better than this Airnergy device--at least based on the principles of operation claimed by the company peddling it.
Say, how did people think light can transfer into electricity?
If you think this isn't real, how could you tell us your math is true then?
I agree, that a single source of wifi is not efficient enough to charge a cell phone or any other electronic device, but if you are in a city, you may have access to more than one wifi point, and so you could start adding coefficients that will mulitply the energy gathered. Like in a apt complex, you may have ten wifi points to gather from.
Is it any wonder that 50% of Americans believe the earth was created 4,000 years ago. For heavens' sake. A WIFI transmitter puts out a fraction of a watt... radiated signals diminish exponentially away from the aerial. I don't care WHAT RCA are claiming, the power that thing is going to pick up is TINY - people really are gullable.
So JGalt 10 wifi sources instead of 1 surely that means it would take 3.4 years to charge the blackberry instead of 34 years well that makes all the difference sign me up I'm sold.
wow all this talk of science... finally i thought no scientist would post smart stuff here lol me no smurt. :)
CriticalThinker wow i cant beleive you dont know this works.
blackspike2710 do you really believe that if something is for sale it must work, if so send my your e-mail and I'l sell you some crap!
....and remember that the Airnergy is =not= a product--yet. If they release a real device later this year for $39 and it works as described it will revolutionize EVERYTHING.
The logical progression of this alleged technology will mean no more batteries in any small electronic device.
Anywhere. (At least anywhere in range of a WiFi signal.)
Remote controls for your TV will sip 'free' WiFi energy. Previously solar-powered path lights in gardens will never go out. Clocks will never need to have replacement batteries. Smoke and carbon monoxide detectors will never need batteries. Home security alarms will never need battery power. Car batteries will trickle-charge and no one (in the city at least) will ever have a dead car battery.
And ask yourself: is any of =that= even remotely probable? Because if the Airnergy device can charge a Blackberry battery in 90 minutes it can power all of those things I described above, continuously, forever--just on WiFi.
And how likely is that?
Of all the things to debate, we're debating existing technology? Can we bet money on this? I'm all in!
No we are debating whether it will work in a realistic usable fashion or whether it is just another false promise pay attention!
I would =love= for this device to work.... because part of me really wants to believe in over-unity, free energy, invisible force shields, tractor beams, anti-gravity, and faster than light propulsion. I was one of those kids that wrote off to the classified ad in the back of (yes) Popular Science magazine for the plans to build a few of those things. (I still have them somewhere.)