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Why Can't Smartphones/Tablets/Netbooks Have Supplemental Solar Power???

Discussion in 'Android Lounge' started by Isthmus, May 19, 2010.

  1. Isthmus

    Isthmus Android Expert
    Thread Starter

    I have asked this a ton of times and have never gotten a response. Why is it that no company embeds solar cells on the periphery of the screen (and/or maybe into the body of the case), as a means to generate supplemental power and extend battery life between charges. It's not like the technology doesn't exist. Heck it is used in exactly that way in modern solar watches every day (only there it is used as the battery's primary charging mechanism). It seems to me like you could squeeze a fair amount of extra use time out of a charge if you had some supplemental power helping out. That plus the device could continue to recharge on it's own when not in use, by drawing power from any light source.

    It seems to me like it would be an easy way to solve battery life issues in so many devices while avoiding having to install bigger batteries.

    How hard could it be to engineer such a system into a phone or a tablet?Do we have an electrical engineers aboard who could chime in with insight into possible issues with such an approach?

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  2. Quboid

    Quboid Android Enthusiast

    I'm not an engineer but I'm pretty sure the reason is that it would offer nothing like enough charge.

    A watch lasts months, even years, off a tiny little battery with about a 100th of the charge of a smart phone (15mAh versus about 1.5Ah). In very approximate terms, it's a 100th of the capacity and lasts 100x as long, therefore a smartphone equivalent would need 10,000x the surface area to maintain full charge, and that's if it got as much sunlight (which it probably wouldn't, living in a pocket most of the time). To even just top up the device, to add a few hours per charge, would need much more space.

    I have a solar travel charger with a 2.5Ah battery and a solar panel about the size of my HTC Desire, it supposedly takes about 24 hours to fully charge. That would suggest that using most of the phone's back as a solar panel could offer some additional charge, but only if you leave your phone face down in the sun a lot, and even then there is the cost, the additional width and the additional fragility to consider.
  3. uzetaab

    uzetaab Android Enthusiast

    Not to mention the fact that I wouldn't want to leave my phone sitting in the hot Queensland Australian sun all the time, it wouldn't be healthy for it.

    Having said that, they are working on solar power for phones. apparently they have managed to make some screens that have solar panels underneath them, but I doubt that the screens even look as good as a cheap candybar colour screen, nevermind a modern smartphone screen. Hopefully they will keep working on it & we'll have them in some future phone.
  4. Quboid

    Quboid Android Enthusiast

    I'm not holding my breath. Nuclear batteries have much more potential and unlike nuclear power stations, shouldn't suffer from "oh no, nuclear = bad!" morons as they can just stick to their old batteries if they're scared. These are still a long way off too.
  5. Isthmus

    Isthmus Android Expert
    Thread Starter

    that was a wonderful article on nuclear batteries. Thanks so much for posting that. I had no idea that kind of technology was being developed for every day use. Thanks again.
  6. Bluesman2008

    Bluesman2008 Well-Known Member

    Unfortunately, my shirt pocket doesn't get all much sun and I'm not inclined to leave in the backyard facing up. Not trying to be facetious but the question seems a little silly.
  7. IOWA

    IOWA Mr. Logic Pants

    For a million times the juice sign me up for a nuke battery
  8. bluenova

    bluenova OK Computer

    I'll take a nuke battery please!

    Strange, if they are already in use for pacemakers you'd think they would have hit the mobile market already.
  9. IOWA

    IOWA Mr. Logic Pants

    I know right? Imagine going a month without a charge.... wow....

    Tapatalk. Samsung Moment. Yep.
  10. Smg

    Smg Android Enthusiast

    The Japanese have done it:


    And its Water-Proof... lol

    But 10 Minutes for a 2 Minute phone call... hmmm lol
  11. Quboid

    Quboid Android Enthusiast

    10 minutes for a 2 minute call ... I think that answers the question as well as anyone has!

    Nuclear batteries will be different, they will last longer than the phone. You wouldn't have to recharge it. Ever. Plus, the battery would probably be much smaller, resulting in smaller, thinner phones. I wonder why they are available for pacemakers and not phones - they're not used in all pacemakers and I'm sure they're expensive but mass production should bring the price down a fair bit.

    Some sort of wireless charging could be possible in the fairly near future. It would be great to have my phone charging now when I'm in my office and my phone is in my pocket. Of course, it would have to be done in a way that didn't render me sterile which is my initial worry, but then people had that worry about cell phones, wifi, bluetooth and we're still making babies.
  12. Eugene

    Eugene Android Expert

    Thats the problem, solar technology still can't keep up with the load.
  13. Isthmus

    Isthmus Android Expert
    Thread Starter

    Thanks for the smart ass remark. It was a valid question, trying to learn why certain types of technology have not been merged. :mad:


    So if I'm understanding everyone correctly, as a supplemental power source (with the purpose being to extend usable battery life, not to be a primary power source), modern solar cells simply don't generate enough usable electricity quickly enough to significantly increase the use-time of modern rechargeable batteries - at least not in the quantity of cells that could be placed on the available device surface. Does that sound about right?
  14. Quboid

    Quboid Android Enthusiast

  15. takeshi

    takeshi Android Expert

    In my experience solar cells don't provide enough power in full, direct sunlight and that's pretty much optimal conditions for them. Sunlight through glass and artificial light yield even less power.

    Based on what? Gut feeling? You can Google specs for solar cells and power consumption for smartphones.

    Those are famous last words for good reason. ;)

    Most things seem easy when you don't understand the details.

    "Who the heck leaves their smartphone lying in the sun for hours to recharge?" is also a valid question. :p
  16. Isthmus

    Isthmus Android Expert
    Thread Starter

    Thanks for the condescending reply and not bothering to read the acknowledgment of the legitimate explanations immediately prior to your post. sometimes consider that not everyone knows everything and that asking is a way to learn.
  17. bluenova

    bluenova OK Computer

    Wireless chargers exist for years already. There are loads of them on the market, just do a google search for 'charge pad'.
  18. Mama Luigi

    Mama Luigi Well-Known Member

    Wow, settle down and get a sense of humor.
  19. Quboid

    Quboid Android Enthusiast

    Charge pads exist, but your phone has to be lying on them. That's about 0.1% better than plugging it in. I mean wireless with a range of, well, with any range, but at least 5m would mean one transmitter could cover a room.
  20. Bluesman2008

    Bluesman2008 Well-Known Member

    And I gave you a valid response. Lighten up dude.
  21. Isthmus

    Isthmus Android Expert
    Thread Starter

    I just came across a pretty interesting device that might call into question some of the conclussion's being offered above. Check out this solar charger for the Iphone:

    Surge for iPhone 3G and 3G S


    Apparently it is actually approved by apple and can give you 30 minutes of talk time on 3g with a 2 hour charge. this is more along the lines of what I was describing if not used as a primary charger but as supplemental power to extend the battery life. I wonder what is being done differently here that addresses some of the issues posted above.
  22. Quboid

    Quboid Android Enthusiast

    That's pretty neat (the idea, not the green!), but a 2 hour charge for 1/2 hour talking makes it still little more than a device for when you need to make an emergency call and even then, not one with urgency. How much map + GPS will you get for that 2 hour charge? 10 minutes? As commented in this thread, how often would your phone get 2 hours of sunlight?

    I have a Evolution 2500 Solar | Powerfreakz which is a more practical approach, it can store about 1.5 changes of my HTC Desire. I could leave it somewhere sunny at a camp site and take my phone with me and when I get back, recharge my phone. Even if I don't get any sun (living in N. Ireland, I generally don't), it can be wall-charged and thrown in a brief case if I've got a busy day ahead, so I can browse/email/navigate, and then recharge my phone while I'm in meeting. Without it, my HTC Desire would be dying before I got home. At the risk of sounding like a salesman for them (I'm not), it's also nice that it can recharge my iPod and pretty much anything else so next time I go abroad, I'll just need to take this and it's various adapters for different devices and for different power sockets. Shame it's so expensive.
  23. zerocore

    zerocore Lurker

    Give me a nuke battery! I'm sure they'd be safe....right??? lol

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