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Using Air to Recharge Your Cell Phone

Posted by CmdrTaco on from the finally-a-use-for-my-wind-pipe dept.

sanspeak writes "Now you do not have to look for a power outlet to charge your cell phones. Department of Industrial Design at Indian Institute of Technology, Delhi have come up with a mobile turbine which generates around 3 to 4 watts of energy - sufficient to charge a mobile phone. It costs around $4, fits in your pocket and runs on air ;-). What else do you want ?"

42 of 346 comments (clear)

  1. You're going to WHAT?!?! by ackthpt · · Score: 5, Funny
    ... a mobile turbine which generates around 3 to 4 watts of energy - sufficient to charge a mobile phone. It costs around $4, fits in your pocket and runs on air ;-). What else do you want ?"

    First impression of "in your pocket and runs on air" is this is charged by hydrocarbon emissions, i.e.

    I am not "just" farting, I'm recharging my phone, and it's a renewable resource!"
    Logically followed by
    "Now you're going to hold that thing to your face?!?!"
    The device is best suited for coastal areas where the wind flows almost continuously.

    They must eat more lentils there...

    "ahhhhh, go blow yer phone!"

    --

    A feeling of having made the same mistake before: Deja Foobar
    1. Re:You're going to WHAT?!?! by mmaddox · · Score: 5, Funny

      Run, Tommy! Run like the wind! ...Can you hear me now?

      --

      What'dya mean there's no BLINK tag!?

  2. Alternatives by fembots · · Score: 5, Insightful

    Why not use Faraday's Principle of Induction like these LED torches or a windup charger? Both are independent of external factors.

    Hanging out your phone from a car, bus or (shock!) train is pretty dangerous stuff, maybe superman will find this thing handy.

    I hope they haven't patented this technology yet, 'cos I'm rolling out my air-powered fan next month.

    --
    Rock that crushes, Paper & Scissors that don't matter.
    1. Re:Alternatives by antifoidulus · · Score: 4, Funny

      air-powered fan next month.
      Powered exclusively by /. comments!

      --
      Monstar L
  3. Blow or run really fast by nizo · · Score: 4, Interesting

    I can't wait to see people blowing into their phones before they make a call, unless they do what the article recommends:
    The device will help mobile phone users charge their phones while travelling in a bus, a car or a train. All they need to do is -- place the turbine against the wind flow.
    In other words, hold it out the window. Can they get sued when people drop their phones, or lose an arm while holding it out the window?

    --
    I Am My Own Worst Enemy
    1. Re:Blow or run really fast by Anonymous Coward · · Score: 5, Funny

      But that's stealing energy that rightfully belongs to the train operators.

    2. Re:Blow or run really fast by TheCarp · · Score: 3, Insightful

      Lets restate this.... you are really taking energy from the train/bus/car

      You increase wind resistance quite a bit just by opening the window. In fact, it has been noted that you are actually better off using the A/C than opening the window, because opening the window decreases your fuel economy more than running the A/C.

      Now, unless you have one of those 1980s cell phones that are roughly the size of a boombox of the same era, your cell phone uses less energy than your car A/C.

      Frankly opening your window to charge your cell phone is incredibly inefficient and should only be contemplated if you were going to open the window anyway.

      Now... mounting it on your motorcycle.... then you are talking. However you
      are still only transfering kinetic energy of the vehicle going forward against
      the wind into electricity. That kinetic energy is provided by the engine... seems more direct to just get the energy from your alternator.

      -Steve

      --
      "I opened my eyes, and everything went dark again"
  4. No air indoors by KinkifyTheNation · · Score: 5, Funny

    What about us people who never leave the house?

    1. Re:No air indoors by kitty+tape · · Score: 4, Funny

      How do you breathe?

      --
      ----- "Type theory is like pretzels on crack." -- random friend
    2. Re:No air indoors by rtaylor · · Score: 4, Funny

      What about us people who never leave the house?

      Simply place a fan next to the turbine.

      --
      Rod Taylor
  5. What else do you want? by SeanTobin · · Score: 5, Funny

    Great.. A cell phone that charges by air. Now all I need is a light weight air compressor with an efficiency greater than unity and I'll never have to plug my phone in again! At least, I won't have to plug it into anything aside from the turbine and the perpetual motion machine.

    I still prefer the alternator strapped to a cat with a slice of buttered toast strapped to its back.

    --
    Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
    1. Re:What else do you want? by SeanTobin · · Score: 5, Funny
      If you think about it carefully, the buttered toast has to be strapped to the cat's feet ;-)
      Not in the "classical" buttered-toast-on-cat scenario. In the classical scenario, a slice of buttered toast it attached to the back of the cat (usually with duct tape) so that the buttered side is facing up if the cat is standing on its feet. When the cat-buttered-toast object is dropped from any height two laws regarding the components come into play. Firstly, a falling cat will always land on its feet. Secondly, a falling piece of buttered toast will always fall buttered-side down. When the cat-buttered-toast object falls, one of the "laws" will be violated assuming the cat-buttered-toast object does indeed hit the ground. Again, in the classical scenario the cat either ends up perpetually spinning above the ground, or simply floats in mid air.

      In your example you are using a non-traditional cat-buttered-toast model in which the cat is placed on top of the buttered toast in such a manner that the cat ends up with buttery paws. This model is not used for various reasons. Firstly, the difficulty of attaching toast to all four paws of the cat is at least an order of magnitude greater than simply attaching the toast to said cats back. Although various attempts at slicing the toast have overcome this difficulty, the amount of effort required is always greater than attaching the toast to the cat's back.

      In any event, the results of the non-traditional model are usually the same as the classical. Our cat with buttery paws is dropped from a height and attempts to land on its feet, however the toast that is attached to its feed attempts to land buttered-side down.

      Now, it should be noted that defenders of the classical scenario usually point out that the toast, relative to the cat, has already succeeded in landing buttered side down by the nature of it being attached to the cats paws. If the cat were to hit the ground while standing on the toast, it would be akin to someone steping on a slice of toast after it has already landed on the floor, buttered side down. Basically it would be irrelevant as the goal of the toast to attach its buttered side to a surface has already been acomplished.

      So, although I used the traditional buttered-toast-on-cat model and the non-traditional models are at least partially flawed, I believe I made the correct decision in its use.
      --
      Karma: SELECT `karma` FROM `users` WHERE `userid`=138474;
    2. Re:What else do you want? by qbwiz · · Score: 3, Insightful

      What if the cat merely lands on its feet? The buttered toast will never land, and so the complex won't need to hover. That's the advantage of strapping the toast to the cat's feet, if you believe that the toast has not landed when you do so. If it lands, either the unbuttered side of the toast must touch the ground, or the cat's feet must not be down. There is no middle ground where one can land and the other does not, as there was with the previous model.

      --
      Ewige Blumenkraft.
    3. Re:What else do you want? by Noofus · · Score: 4, Funny

      I attempted this experiment. I tied a piece of buttered toast to my cat's back and dropped him off the side of the table. The cat landed on his feat and the toast slid around his body under the string and hung, butter side down, on his belly. It then slipped out of the string and fell butter side down on the floor.

      Granted my experiment might have been more sound with better method of toast attachment, I do believe this proves that neither law can be violated. Were I to more securely attach the toast some other method of getting both the toast butter side down on the ground and the cat on its feet would present itself ;)

  6. well, for one thing... by EsbenMoseHansen · · Score: 4, Funny
    ...what else do you want

    Does it run linux?

    --
    Religion is regarded by the common people as true, by the wise as false, and by rulers as useful.
  7. Re:and... by cayenne8 · · Score: 3, Funny
    Was that turban or turbine?

    :-)

    --
    Light travels faster than sound. This is why some people appear bright until you hear them speak.........
  8. What else do you want ? by davecb · · Score: 5, Funny
    How about an adapter to connect it to my propellor beanie?

    --dave

    --
    davecb@spamcop.net
  9. compressed air by psyklopz · · Score: 4, Interesting

    I once thought that it might be an interesting idea to store compressed air in a tank and then let it out at a controlled rate to run a turbine.

    In essence, the compressed air tank would be a battery (it would 'hold' the energy that was used to pump the compressed air in).

    I don't know a lot of about high pressure tanks. Does anyone know if this would work at all? Would all the air come out too quick to make it worthwhile?

    1. Re:compressed air by rd4tech · · Score: 5, Funny

      buy a second batery

    2. Re:compressed air by mmontour · · Score: 4, Informative

      I don't know about individual off-grid use, but this idea has been used commercially. Here's one link.

      There's also a compressed-air car.

  10. What's next? by bigtallmofo · · Score: 4, Funny

    We've seen hand cranking chargers, now windmill charging... How long until someone packages and sells a DIY Dam & Hydroelectric Cell Charging kit?

    Also, I understand that Iran is currently importing plutonium from Russia in an attempt to make a personal, portable nuclear reactor capable of charging cell phones.

    --
    I'm a big tall mofo.
  11. But, by jim_v2000 · · Score: 5, Funny

    How long does it take to charge, and wouldn't you have to leave it somewehre with a constant air flow? Like, outside, or in front of a fan, or does it strap to your side so it uses the breeze when you walk?

    I can just imagine someone talking and their battery's about to die, and all the other person on the other end hears is "Wait, my phone is dying...hold on a sec *blowing sound* Ok, now where were we..*blowing sound*...Oh yes, about the *blowing sound*..."

    --
    Don't take life so seriously. No one makes it out alive.
  12. air vs wind by Hanzie · · Score: 4, Interesting

    I think it might be a little more correct to substitute "wind power" for "air" in the writeup.

    Essentially, the idea is to incorporate a windmill to power the phone.

    Saying the phone is "Air" powered implys (to me, at least) that some chemical reaction is taking place using oxygen or nitrogen.

    It is a cool idea, and the article implies that normal winds are sufficient to power the cell phone.

    If the generator is small enough to actually be part of a cell phone, I'd think that scaling the design up might make economic sense for generating normal electric power. Unfortunately, there weren't any specifics, so it is tough to make any extrapolations.

    --
    ********* sig: If you don't like the law, get filthy stinking rich, and buy a better one.
  13. Other good uses too by nizo · · Score: 5, Funny

    I just realized, there are other good uses for "blow phones" too: simply add a breathalyzer to avoid those embarrassing late night drunken calls to your ex.

    --
    I Am My Own Worst Enemy
  14. Ok then... by Cheerio+Boy · · Score: 3, Interesting

    Tell me why if this model produces 3 - 4 watts of energy why they can't cover the blades of larger windmills with these things or better yet design the blades so they have edge holes with these things inside.

    The wind blows the large blades which causes air to flow through the smaller fans.

    Of course you could probably put up walls of these things in windy areas and get the same results.

    Any thoughts on this?

    --

    "Bah!" - Dogbert
    1. Re:Ok then... by whitis · · Score: 3, Informative

      Tell me why if this model produces 3 - 4 watts of energy why they can't cover the blades of larger windmills with these things or better yet design the blades so they have edge holes with these things inside.

      There is no such thing as a free lunch (1st law of thermodynamics). The drag produced by the turbines extracting energy slows the speed of the windmill blades reducing the power delivered to the main generator so you gain nothing by adding those (more likely you will lose since the main generator is less efficient at slower speeds).

      Coincidently, this is the same problem with charging the cell phone by clipping this device to the outside of the window while riding in a bus, train, or car. The vehicles engine needs to consume more energy to offset the drag produced by the turbine. Granted it is small compared to the amount of energy used to move the vehicle in the first place but it would be more energy efficient to connect the phone to the vehicles alternator than to convert the engines rotory motion to motion induced "wind flow" and then the wind flow back to rotary motion.

      Now could you make a windmill with no main generator and use a large number of small turbines instead? Yes but it probably would not work well at all. In fact, it would probably work less well than just pointing the turbines into the wind which in turn would not work very well at all. The problem is a serious impedance mismatch. Turbines want high pressure/high airflow. A windmill blade tip will be travelling at a lower linear velocity than the air that turns it.

      Incidently, power from wind is proporional to the cube of the wind velocity. Generators are inefficient at low speeds. Modern windmills adjust to different wind velocities by feathering the blades to try to run the generator at a relatively constant speed. In really high winds they turn the blades parallel to the airflow to avoid destroying the generator and gear train.

      Note that since it was described as a turbine and not a "wind turbine" (which is normally a very different beast) and described it as fitting in a pocket, I am imagining a device with multiple disks with the edge shaped into blades inside a tube like you might find in a jet engine or gas fired power plant (every other disk is stationary or counter rotates to restore longitudinal airflow). A friend built an toilet paper roll cardboard tube sized device out of sheet metal in this topology that was demonstrated with the air from a shop vac that would be about the right size for a cell phone charger. If that is not the topology used., then some of what I have said will not apply but much of it still will.

      Whatever turbine topology you use on your windmill blades, you are converting from wind to rotary motion twice and therefore are reducing the efficiency by around 60% compared to doing so once even if it is well designed and operating at optimal wind speed. And poor performance at low speeds will be made even worse by being being run twice through the innefficent portion of a non-linear transfer function.

      Back to the original article, the usefulness of this is likely to be very limited since people in India who don't have electricity aren't likely to spend a lot of time running around in vehicles every day to charge their phones. A small roof mounted windmill would probably be a lot more practical. It may have some use as a travel charger for people who will be traveling to distant points but not be staying for very long (such as tourists).

      The little generators that run headlights on a bicycle might be another alternative for charging a cell phone. With a stand, pedal power can even be used while stationary. Someone built a generator stand for a bicycle that was capable of generating as much as 260W (100W seems more likely for an extended period of time).

      A small solar panel with built in battery (so you don't need to leave your cell phone on char

  15. Re:uhh... by Tackhead · · Score: 4, Funny
    > > "It costs around $4, fits in your pocket and runs on air"
    >
    > Is that a turbine in your pocket or are you just happy to see me?

    From the Department of Industrial Design at Indian Institute of Technology, Delhi.

    I believe you meant to say "Please be telling me is in your pocket a turbine, or are you happy to be seeing me?"

    Now, if you'll pleased to be pardoning me, I have another caller in my queue. Some woman named Paris Hilton needs to be blowing on my hard drive to reboot her Windows.

  16. A better idea! by STratoHAKster · · Score: 3, Insightful

    They sell radios that can be charged by turning a crank, why not sell a cell phone charger that works that way?

  17. wind? by Loconut1389 · · Score: 3, Funny

    "What else do you want?"

    -wind?

  18. Crank Alternative by 4of12 · · Score: 4, Interesting

    Compressed air is an interesting idea for storing energy.

    But I have to wonder how it compares to the alternatives.

    How about a capacitor bank and a hand-crank generator?

    If you're out of compressed gas or batteries in the middle of nowhere it's hard to replenish your cell phone. Turning a hand crank would make use of cheap, available human power.

    --
    "Provided by the management for your protection."
  19. You've obviously not seen by donutello · · Score: 4, Funny

    ... how people travel in India.

    --
    Mmmm.. Donuts
  20. $4? No it doesn't by DrXym · · Score: 4, Insightful
    If / when it appears in a commercial form it might costs $4 in India perhaps. But in the US it will cost $50.

    Why? Because people are suckers.

  21. Re:compressed air: not efficient by spectrokid · · Score: 3, Insightful

    there's this physics law that sais air gets hot when you compress it. If the tank is not insulated it will cool down to room temperature again and you lose quite some energy. There are however examples, there is even a car which runs on compressed air, and in the good old days of steam, they used comp. air locomotives e.g. in ammo factories and other places where you might want to avoid fire.

    --

    10 ?"Hello World" life was simple then

  22. 4W for $4 would be significant by shlashdot · · Score: 3, Funny

    That's $1 per watt, which is the holy grail of renewable energy technologies, being the approximate cost of conventional power plants.

    --
    Additional plugins are required to display all the media on this page.
  23. RTFA by Short+Circuit · · Score: 3, Informative

    They're not talking about hanging the things out of car windows. A 12V adapter would be better for that, anyway.

    Instead, they're expecting that typical environmental wind, especially that found on coasts, will work well enough. The idea is to ease communications access to areas without convenient electricity. (Mountain climbing, anyone?)

    --
    tasks(723) drafts(105) languages(484) examples(29106)
    1. Re:RTFA by Anonymous Coward · · Score: 3, Funny

      Err... why would hanging a 12V adapter out of a car window be better? I don't quite get that.

  24. yeeeeeeehaw by Anonymous Coward · · Score: 5, Funny

    That was really funny. It would be good for people who run in rodeos and then go home and ranch their cattle because there is a lot of wind on the praire and they would be riding around on horses, which is a lot of fun.

    The wind would blow, and then the battery would get really recharged. They could talk forever:
    Sample conversation

    Customer service: This is a Sprint customer service person, how may help you?

    Cowboy Neal: I would like to order some pizza
    ?

    Customer service: This is not a pizza place, this is Sprint Customer service

    Cowboy Neal: Oh, sorry, I just pressed some random buttoms because my battery is really charged up.

    Customer service: Oh you have one of those new air chargers, those are really cool

    Neal: Yeah, I like them a lot.

    Sprint customer service: Hey have you played Zelda: The wind waker?

    Cow Boy Neal: I hear it is awesome.

    Sprint person: Can you hear me now.

    Cow Boy Neal: Yes.

  25. ACME Industries. by Jeremiah+Cornelius · · Score: 4, Funny
    O.K.,

    I have a hundred of these, mounted on the roof of my Prius. Next...

    --
    "Flyin' in just a sweet place,
    Never been known to fail..."
  26. If only they could scale this technology up.... by mikael · · Score: 4, Funny

    .... then we could have an electric powered car which recharges the battery automatically.

    --
    Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
  27. Or, better yet, buy one of those cables... by PaulBu · · Score: 3, Informative

    ... to charge your phone from your car's battery!

    Paul B.

  28. Re:Now.. by narcc · · Score: 4, Funny

    No, but I have a go-cart that's powered by my own sense of self-satisfaction...

    --
    Required reading for internet skeptics
  29. Perfect for motorists! by Cyn · · Score: 4, Funny

    Now if your cell battery starts to get low while chatting to your friend while driving, you can just crank up your A/C, roll down your window, and hold one arm out the window while you eat and change the radio station with the other.

    Or for when your battery is a little low, but you just really need to call someone - you can blow on your phone for a few minutes, then pass the phone to a friend (if you have any left) and they can call 911 since you're hyperventilating.

    Seriously, in public transportation - of the times when you can hold your phone up to a window - you might want to purchase some tshirts that say "I'm an idiot, steal my expensive phone after I get off the bus". Any other times, you should be able to find a much more efficient and timely manner of charging your phone. Windows down + A/C up == your car is burning excess energy.

    --
    cyn, free software and *nix operating systems enthusiast.