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Solar LCD Powered iPods, iPhones and Laptops?

so today I read about solar cells that could achieve a 44% output. It's likely a ways off, but I'd love to see these two worlds collide
Analog Kid said:
...I was responding to the idea of using the LCD backlight to recharge the batteries. There's no point in using your batteries to generate light to power a solar cell to charge your batteries. You can see the energy loop here, you can't extend the battery life this way-- you're just generating more heat at every conversion.
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I think the person was saying that the solar cells would be used to generate a charge during normal use. Though I don't think that the backlight produces much, if any, backscatter. I don't think he was suggesting that it could be used to create a new charge, but rather to get back some of the energy it is using. This sort of thing is very common in manufacturing where steam produced by A is redirected to power B. No one imagines it is endless (perpetual) energy, but rather a way to use the energy more efficiently.
 
John, read some stuff

John454 said:
Great idea but... it amazes me how after time and time again Apple takes other people's ideas twists them ever so slightly and tries to patent it like they invented it.
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John, you should really read up on the requirements for patents, then you wouldn't be "amazed". It's not hard. If (using your words) Apple "twists" other people's ideas, that makes the idea "unique" and not obvious, which satisfies one of the legal requirements for an approvable patent application.
 
I remember, nearly a decade ago, seeing a solar cell battery extender for PowerBook 1400 - it took advantage of the 1400's customizable faceplate and replaced the plastic/paper panel with a solar cell and a little cord that would run to the power-port. I seem to recall there being a brick in-line with the cord, as well.

Anyway, this device was supposed to be able to double the battery life of the 1400 under ideal conditions, but because it was so low current, would not have been able to charge the battery.

It seems like Apple's just integrating this kind of technology into the package. Perhaps it means that on Pacific flights from the US (or Atlantic flights from Europe), if you get a window seat, you could conceivably work/watch movies for the entire flight without having to swap out batteries.
 
jonnylink said:
I think the person was saying that the solar cells would be used to generate a charge during normal use. Though I don't think that the backlight produces much, if any, backscatter. I don't think he was suggesting that it could be used to create a new charge, but rather to get back some of the energy it is using. This sort of thing is very common in manufacturing where steam produced by A is redirected to power B. No one imagines it is endless (perpetual) energy, but rather a way to use the energy more efficiently.
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Right, but it's redirected as steam. Produced once and used several places. That's the equivalent to using a fiber optic pipe to bring light from the display backlight to light the keyboard. If you need electricity somewhere else, you don't go from electricity to light and back to electricity-- at least not for something like this. You're better off using a reflector and dimming your backlight so you use less power to start with.
 
Rot'nApple said:
Yeah, and people know that driving on the interstate at 55 - 60 mph saves gas... the 60 mph thing, it ain't happening!


"can get a boost and keep itself charged by lying in the sun, some users would alter their behavior to take advantage of this ability" and some users won't alter their behavior to justify the expense, and by expense I mean, I would rather see the price of the iPhone drop then have the price always remain the same or with very little fluctuation down, but be "wooed" by SJ and company about a feature I could do without in it's next product revision.
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"'can get a boost and keep itself charged by lying in the sun, some users would alter their behavior to take advantage of this ability' and some users won't alter their behavior to justify the expense" and won't buy the iPhone.
 
PV charged devices already exist.

My Casio Pathfinder wristwatch has an embedded solar cell on the watch face. They call it Tough Solar Cell technology. I've had it since 2003.
 
ibjoshua said:
Yeah. Sounds like we're going around in circles here. I'm sure someone said the same thing earlier.
ibjoshua
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Probably me, but I can't give up or people get offended...
ftbotsb said:
My Casio Pathfinder wristwatch has an embedded solar cell on the watch face. They call it Tough Solar Cell technology. I've had it since 2003.
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How well does it work in the basement of the science building?
 
christian_k said:
I dont't think that will work.

The "nominal" sun radiation is 1000 W/m^2, which is quite bright sunlight. The best commercial solar cells have an efficiency of about 18.5% (we assume the display does not absorb any light), this gives you a nominal power output of 185 W / m^2. The display of a MacBook is about 0,3 m x 0,2 m = 0,06 m^2, so its nominal power output would be about 11W. But only in bright direct sunlight!. The rule of thumb for planing photo voltaic in middle Europe: Over a period of a year you get energy that is equivalent to the nominal power for 3 hours a day. That is 33 Wh per day. If battery and charger are very efficient you would still need 2 days to charge a standard 60Wh notebook battery without using the device the at same time.

This only if you really use that thing outside. (A MacBook is not really an outdoor device). The light inside of buildings is usually less than 10% of what is outside. Everyone who takes photos has experienced that. Charging the battery under such conditions would take weeks.

And no. Holding an iPhone towards the sun for a few minutes won't give you hours of talk time. There are commercial solar chargers for mobiles. They usually take days to charge a battery.

Christian
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Thanks for the details. How does this play with the Touch? That seems to be what the patent targets (portable media players). I get a one-sided surface area of 0.007m^2, which is a reasonable estimate for exposed area considering Apple is talking about putting cells on both sides.

That gives me 1.26W of power using your 18.5% efficiency number. That's probably not far from the operating power of the device. Granted that's in full sunlight, but not a bad showing if you ask me.

Apple also seems to cover the fact that it's much more efficient to power the unit directly when the unit is operating because you don't loose efficiency in the charger.

It sure helps that Apple has been so obsessed with thin and flat.
 
This is SUCH a great idea! I'd love to see it in iPods and laptops :)

As some have mentioned, it might have the side benefit of recovering some power from the backlight.

I'm not sure why some people have said it wouldn't work inside....why not? If there's enough light to see by, the solar panels will be generating power. Even if it's plugged in at my desk, and even if it only cuts power use from 50 watts to 45 watts (I'm just making those numbers up), that would still add up massively over time and over the number of devices Apple sells.

REALLY neat thing! I love solar power! I wonder if Al Gore's had anything to do with this development? :)
 
Not like I'm an expert here, but I don't think this is that practical, especially when slim design is key. I would think a solar energy converter would take up too much space, considering the proposed memory upgrade and 3G chip addition..............Gonna whip out my solar powered :apple: iCalculator! :D
 
sam10685 said:
Really good idea but do LCD lights generate the same kind of solar light?
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Well not solar light of course, but virtually any light source will power solar panels. At least any I've used work just as well under florecent and incandecent light as they do under sunlight. I don't know about LED lights, but I'd assume they work too (I think they must be converting visible light, as I don't think incandescent give off UV, and florescent don't give off all that much...at least supposedly)
 
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