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Using Air to Recharge Your Cell Phone
Posted by
CmdrTaco
on Thu Feb 24, 2005 03:00 PM
from the finally-a-use-for-my-wind-pipe dept.
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 ?"
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You're going to WHAT?!?! (Score:5, Funny)
First impression of "in your pocket and runs on air" is this is charged by hydrocarbon emissions, i.e.
Logically followed by 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!"
Re:You're going to WHAT?!?! (Score:5, Funny)
Parent
yeeeeeeehaw (Score:5, Funny)
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.
Parent
ACME Industries. (Score:5, Funny)
I have a hundred of these, mounted on the roof of my Prius. Next...
Parent
Alternatives (Score:5, Insightful)
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.
Re:Alternatives (Score:5, Funny)
Powered exclusively by
Parent
RTFA (Score:3, Informative)
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?)
Re:RTFA (Score:3, Funny)
Re:Alternatives (Score:3, Interesting)
http://windupradio.com/ [windupradio.com]
Re:Alternatives (Score:3, Interesting)
Because I've used one of those, and they royally suck. The light is nearly worthless. I blame this on their reliance on an ultracapacitor rather than rechargeable batteries. Batteries would enable the use of more LEDs, making the light a lot more useful. Nothing wrong with Faraday induction, just that's a HORRID example of it.
Also, doing this in a fone would require substantial empty space and weight, neither of which seems to be all that
Or, better yet, buy one of those cables... (Score:4, Informative)
Paul B.
Parent
Blow or run really fast (Score:5, Interesting)
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?
Re:Blow or run really fast (Score:5, Funny)
Parent
You've obviously not seen (Score:5, Funny)
Parent
Re:Blow or run really fast (Score:3, Informative)
Re:Blow or run really fast (Score:3, Insightful)
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
No air indoors (Score:5, Funny)
Re:No air indoors (Score:4, Funny)
Parent
Re:No air indoors (Score:5, Funny)
Simply place a fan next to the turbine.
Parent
What else do you want? (Score:5, Funny)
I still prefer the alternator strapped to a cat with a slice of buttered toast strapped to its back.
Re:What else do you want? (Score:5, Funny)
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.
Parent
Re:What else do you want? (Score:4, Insightful)
Parent
Re:What else do you want? (Score:5, Funny)
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
Parent
well, for one thing... (Score:5, Funny)
Does it run linux?
What else do you want ? (Score:5, Funny)
--dave
compressed air (Score:5, Interesting)
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?
Re:compressed air (Score:5, Funny)
Parent
Re:compressed air (Score:3, Interesting)
-Jesse
Re:compressed air (Score:3, Interesting)
If it would work and provide enough energy, it would also be an environmentally friendly way to store energy for later use.
Kind of the same idea as pumping water into a tower and then later opening the tower at the bottom and using the flowing water to run a generator. In essence, the water tower is your battery, because it is storing e
Re:compressed air (Score:5, Informative)
There's also a compressed-air car [theaircar.com].
Parent
Re:compressed air: not efficient (Score:4, Insightful)
Parent
What's next? (Score:4, Funny)
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.
But, (Score:5, Funny)
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*..."
Re:But, (Score:3, Funny)
air vs wind (Score:5, Interesting)
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.
Re:air vs wind (Score:3, Interesting)
To me, Turbine means a multi stage fan, that uses compression of the 'Air'.. If I have to hold it out the window at 60mph to get it to work, its a damn pinwheel.
Other good uses too (Score:5, Funny)
Ok then... (Score:4, Interesting)
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?
Re:Ok then... (Score:4, 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 [erols.com] 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
Parent
A better idea! (Score:3, Insightful)
wind? (Score:4, Funny)
-wind?
Crank Alternative (Score:5, 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 [electricitystorage.org] bank and a hand-crank generator [pasco.com]?
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.
$4? No it doesn't (Score:5, Insightful)
Why? Because people are suckers.
4W for $4 would be significant (Score:3, Funny)
Whistle? (Score:3, Interesting)
Adolfo
If only they could scale this technology up.... (Score:5, Funny)
Perfect for motorists! (Score:5, Funny)
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.
Re:and... (Score:4, Funny)
Parent
Re:uhh... (Score:5, Funny)
>
> 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.
Parent
Re:Now.. (Score:5, Funny)
Parent