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Cellphones Power

Nokia: the Sun Can't Charge Your Phone 290

Posted by Soulskill
from the well-what-am-i-going-to-do-with-this-93M-mile-cord dept.
itwbennett writes "Nokia's research into solar-powered cell phones ended with a (barely audible) thud. Under the best of conditions researchers were able 'to harvest enough energy to keep the phone on standby mode but with a very restricted amount of talk time,' Nokia wrote in a blog post on Tuesday. Not surprisingly, the prototype phone, which had a solar panel on the back cover, performed better in Kenya than in other testing locations, like southern Sweden and the Arctic Circle."
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Nokia: the Sun Can't Charge Your Phone

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  • by bugs2squash (1132591) on Tuesday January 03, 2012 @08:05PM (#38580316)
    a tablet then
  • by TWX (665546) on Tuesday January 03, 2012 @08:06PM (#38580326)

    My phone resides in my pocket. Even if I left it on the dash of my car, the casing is only so large, even on my Galaxy S II. I don't see how even the most efficient of solar panels in the most effective of locations would provide enough power.

    It's noble of them to try, but at the moment I'm not surprised this was the outcome.

    • by bmuon (1814306) on Tuesday January 03, 2012 @08:10PM (#38580372)

      No idea. Mechanical energy -motion and/or sound waves- seems a more likely source of power for a phone.

      • by khallow (566160) on Tuesday January 03, 2012 @08:48PM (#38580648)

        Mechanical energy -motion and/or sound waves- seems a more likely source of power for a phone.

        They don't have the power density of a solar cell and the mechanical energy approach would add considerable mass.

        Looks to me like they'll just have to figure out how to make a much lower power cellphone. That process will be limited by the need of the phone to produce sound that one can hear.

        • by pz (113803)

          I'm thinking the limitation will be the amount of power used when communicating with the local network. When transmitting, cell phones blast out a fair bit of RF power, on the order of 1 W, if memory serves. Audio, on the other hand, is easy to do with 10 mW or so when the speaker is near one's ear. Moreover, even in standby mode, phones still periodically connect to the local network which requires bursts of high power.

        • by GreatBunzinni (642500) on Tuesday January 03, 2012 @09:22PM (#38580896)

          ...or, you know, sell a separate battery and a stationary solar powered battery charger. That would avoid the size constraints on the solar panel and the exposure problem.

          The only problem with that obvious approach is that such a charger couldn't be used to sell expensive phones under the pretext of Nokia being environmentally-friendly and all the associated fraudulent propaganda. ...and so the project is scrapped.

          • by Fluffeh (1273756)

            such a charger couldn't be used to sell expensive phones under the pretext of Nokia being environmentally-friendly and all the associated fraudulent propaganda. ...and so the project is scrapped.

            I actually don't see why they killed it. I would have paid an extra hundred bucks to have a phone with a longer battery life. My Galaxy S II barely gives me a day, if with a solar panel it would give me a day and a half, at least it would last without problems until I get home from work. Worth it in my books.

            • You don't have electricity where you live? You can get a USB charger for household mains, cars, boats, airplanes - all manner of civilized accoutrements. You could even charge your phone while wasting your time here at Slashdot! At least you'd be doing something useful.

              • by Hadlock (143607)

                I leave my phone plugged in when I'm not using it, but I miss my old blackberry that I could leave off the charger for a day and a half and still check my email. If I didn't use it at all, it would happily sit there for 2 or 3 days. There's nothing wrong with wanting a more efficient phone. When I bought my android phone I had to buy a car charger and 2-3 extra charging cables, and stuck a spare wall charger in my glove box.

                At one point they were called "mobile phones". Now they're "you have 45 minu

            • Re: (Score:3, Informative)

              by Anonymous Coward
              They killed it because it didn't work. Didn't you even read the summary or the article title? Although they should have been able to figure out that it wouldn't have worked based off calculations before they left the office. I'm cynical so rather than give them credit for testing prototypes, I think they must have known it wasn't going to work, but tested it anyway as a PR stunt.
              • by tragedy (27079)

                They killed it because it barely provided enough power to keep the phone in standby, if that. That's not the same as not working. The GP was interested in anything that would prolong battery life. Whether or not it would usefully prolong battery life is another question. It depends on the users usage pattern. Someone who doesn't actually spend a lot of time on the phone might find this very useful to their battery life. Someone who uses their phone a lot, on the other hand, would probably use up their batte

          • by demachina (71715)

            Adafruit has this, sort of, would need some packaging, its geared towards hardware hackers, Solar LiPo charger [adafruit.com] plus Minty Boost [adafruit.com]

          • by bemymonkey (1244086) on Wednesday January 04, 2012 @02:38AM (#38582610)

            You know you can buy solar panels with buffer cells and ~1000mA USB output for about $200, right?

            I'm looking at getting this next time I have a little too much cash laying around: http://www.amazon.de/Aurora-Solarladeger%C3%A4te-Handys-iPhone-MP3-Player/dp/B0049U3GQC/ref=sr_1_6?ie=UTF8&qid=1319908425&sr=8-6 [amazon.de]

            Add a ~5000mAh battery pack (good for about two or three charges of my smartphone) and I'm set for camping, festivals and the like... panel + battery pack are placed in the car during the day, and the phone gets charged off of the (hopefully full) battery pack at night.

        • by trawg (308495) on Tuesday January 03, 2012 @10:33PM (#38581398) Homepage

          Not really related, but I recall John Carmack recently posted on Twitter [twitter.com] saying that a cell phone will use less than $1 of grid electricity over their lifespan (based on this calculation [twitter.com]).

          Interesting insight into how little power a cell phone uses compared to other devices!

          • by Grishnakh (216268)

            Sounds suspiciously low, unless the phone is thrown away after only a year.

            But did he account for all the power used by the phone's charger as it's left plugged in all the time, even if the phone isn't attached?

            • by quacking duck (607555) on Tuesday January 03, 2012 @11:59PM (#38581898)

              Don't know about other phone chargers, but my iPhone USB charger block registers 0W on my watt meter when the cable is plugged in but no iPhone is attached.

              • by Grishnakh (216268) on Wednesday January 04, 2012 @01:10AM (#38582222)

                1) Your watt meter probably isn't that accurate at low levels like that.
                2) It probably registers everything at some threshold under a watt (assuming it's even that accurate) as "0". But 0.5W 24/7 for a year is still 4383 watt-hours. Sure, it's probably only between $0.44 and $0.66, but it's still enough to dry a load of clothes in a dryer, maybe two. And that's still a good fraction of that supposed $1 lifespan total, for only one year of usage.

                • My PVR uses 25W on standby, 29-30 when it spins up the hard drive (in standby or on). It's the worst electricity "vampire" device I have, and I had planned to get a powerbar with a timer to switch stuff off during the night and during weekdays when I'm at work. So figure about 0.65 kW/h a day, or about 5c (10c with "delivery charge").

                  Then our province-mandated smart meter program finally kicked in and I could see which hours of the day I was using the most electricity. It corresponded to my daily hot shower

            • by nedlohs (1335013) on Wednesday January 04, 2012 @12:31AM (#38582046)

              Over 3.5 years for me (by the numbers in that link) - my phone does a discharge/charge cycle once a day basically.

              It's hardly suspiciously low.

              My phone has a battery in it with 3.7V and 1300mah. My old high school memories tell me that P=IV, so 1300mah*3.7V = 4.8Wh. My electricity bill says that the distribution charge is $0.0654531250/kWh and the energy charge is $0.113187500/kWh (more expensive than the original calc used, and by lord how many decimal places do they want to use...)

              So one charge would cost if that was the price of abstract electricity:
              (0.0654531250+0.113187500)/1000*4.8 = $0.00086

              So $1 gets me 1166 charges, at once a day that's 3 years (Wh are likely higher due to the voltage actually being higher when fully charged, but we have enough slop over 3 years to cover that).

              The charging efficiency while not 100% is high enough that it is more than covered by the fact my phone doesn't actually get to 0 charge each day - it tends to have 25% or so left.

      • This is probably a smarter option.

        Even if you can't charge your phone fully with tech like this, at least you can extend the standby time.

      • by Anonymous Coward

        A 100dB sound pressure at 10cm (lets assume you can achieve that by screaming very, very loudly into the phone, say when you're talking to your boss ;-) will have a sound power of maybe around 90dB (sound power & sound pressure are two different things).

        As sound power is referenced to a level of 1 picowatt, 90dB represents an actual acoustic power of 0.001 watts. This is how much power you're putting into that scream. The phone only sees a small part of it, the rest 'leaks' into the surrounds (letting

        • by frdmfghtr (603968)

          Even microphones, which are specifically designed to be as efficient as possible in converting sound waves into electrical signals, usually require pre-amplification before you can do anything useful with the signal.

          Usually, but not always. The Navy uses sound-powered (wired) phones on all the ships and subs, and they work quite well. Maybe slightly offtopic, but I thought I'd point it out.

    • by timholman (71886) on Tuesday January 03, 2012 @08:14PM (#38580396)

      My phone resides in my pocket. Even if I left it on the dash of my car, the casing is only so large, even on my Galaxy S II. I don't see how even the most efficient of solar panels in the most effective of locations would provide enough power.

      It's noble of them to try, but at the moment I'm not surprised this was the outcome.

      I don't doubt that Nokia's engineers did some quick calculations and told their managers that solar charging wouldn't be practical before this project even got started.

      And then the managers said: "It doesn't matter. It'll look great in a press release. The environmentalists will love it. Do it anyway."

    • by viperidaenz (2515578) on Tuesday January 03, 2012 @08:22PM (#38580456)
      You can get 0.5W panels about the size of a smart phone for $2.00 [seeedstudio.com]. considering they only have a ~5w/hr battery it should be possible to get an 80% charge in 10 hours. The problem being that solar power drops significantly when not in direct sunlight, partially covered, through glass, not perpendicular... etc.
      • You can get 0.5W panels about the size of a smart phone for $2.00 [seeedstudio.com]. considering they only have a ~5w/hr battery it should be possible to get an 80% charge in 10 hours.

        Most places you only get about 6 hours of good solar power.. you also have to keep in mind that the conversion to charge isn't 100% efficient and the phone will be on.. even in standby drawing power. Now I have seen a 5 watt 12v panel that's about half the size of a sheet of paper that would work well.

        • That's why I said 80%. The 5whr capcity is a 1350mah battery typical of an android or iphone. feature phones typically have half that capacity and 5 - 10 days standby time. My trusty old samsung lasts 7 days between charges.
          The panel i quoted above is 5.5v @ 100ma, standard nokia wall chargers are 5v @ 350ma. Its also only 17% efficient, if you paid more you could probably find something 20% efficient. That would give you 10% more power output.

          In theory it could work, the only way to know for sure in pra

    • by J0nne (924579)

      Some places don't have reliable power, and it would be pretty beneficial for Nokia if they could sell a phone that had this advantage over other phones aimed at the 3rd world market. As it is now some people now charge their phones by going to special charging shops where you hand over the phone and they hook it up to a charger fed by a generator.

      • by hedwards (940851)

        You'd probably be better off fashioning a generator out of a washing machine motor and a few small components than hoping to have enough sun when you need it to power the phone.

      • by artor3 (1344997)

        I have a portable radio/flashlight from LL Bean that has a little handcrank which can be used to either charge the device itself or any other device connected via USB. Twenty minutes of turning the crank takes my phone from dead to ~30% charge, is not at all tiring, and has the added advantage of working at night. I think that would be a better solution for third world phone charging than solar cells. Maybe even put the crank right on the phone, though that might make it too clunky.

    • by steelfood (895457)

      Where this might work is for the outdoorsy people who are in the woods, but not out of coverage (especially 911 coverage). I know people already bring portable solar recharging stations along with them. Something like this helps by increasing the amount of other equipment that could be included in the trip.

      Cell phones need to be fairly low-powered to be powered directly by straight sunlight. There isn't much surface area for the solar cell, and the efficiency goes down when holding it to the ear. Not to men

    • Stop spreading your right-wing, capitalist 1% lies. iPhones work 30% better off of solar power and organic tomatoes cure cancer. It's a fact.
    • by poetmatt (793785)

      Why should you need to be able to put the phone into a positive charge, aka "lots of power"?? Generating enough power to simply neutralize standby or even diminish it is incredibly significant by itself and could probably add anywhere from small amounts of time to substantial ones merely by basically adding a small amount of charge from solar energy.

    • It has utility: in a rescue situation, it could charge all day if only to provide even a one minute 911 call.... obviously only if in range. Ive been in a situation where the last bit of charge on a cellphone was the factor that led to survival.

      • by itsme1234 (199680)

        Having to wait all night then some big part of the next day (IF it's sunny) doesn't sound such a good plan for a "rescue situation". Now if 90% of the phones would have solar panels on them (while being about the same size/weight as non-solar-panel phones) I would get probably a phone with solar panel "just in case". But if you're planning in advance and there aren't a lot of "solar phones", if any, just get a second battery. It works with your phone and even the cheapest $1-$5 battery on ebay will provide

    • by Grishnakh (216268)

      Maybe they had some dumbasses working there who have the same idea as many people, that you can power an electric car with solar panels. You see it here all the time: "Why doesn't Toyota put solar panels on the roof of the Prius so it doesn't need gas at all?", and this is supposed to be filled with tech people, not morons who don't understand basic physics.

      Either that, or maybe too many of the aforementioned people were bugging them, so they decided to go ahead and waste a little time on a test to prove w

    • All of which are facts that can be determined in 30 seconds of hand calculation assuming (as they do) they know the power it draws. I can't see why they would actually bother to build it.

    • Its for places with no charging infrastructure. Places where people have to pay to charge their phones.

      The blog is here:
      http://solarcharging.nokia.com/ [nokia.com]

    • I spent 3 weeks in the Himalayas last year, with a Power Monkey [powertraveller.com] solar panel strapped to the back of my pack. I figured the odds of a decent charge were good - we were in direct sun for ~8hrs a day, and the UV at >5000m altitude is seriously intense.

      In practise, I usually managed to get enough charge at the end of the day to power up my HTC Desire for about 20mins, with wi-fi turned off and making no calls - essentially using it as a notepad and sending the odd "we're OK!" text to my family. So, not a via

  • by Deathnerd (1734374) on Tuesday January 03, 2012 @08:08PM (#38580342)
    They spent god knows how much money and time to send this team of researchers around the world to exotic locations to talk on a cellphone with a solar panel duck taped to the back of it? Where the hell was THAT career option on career day?
    • Re:So basically (Score:4, Interesting)

      by mrmeval (662166) <[moc.liamg] [ta] [lavemrm]> on Tuesday January 03, 2012 @08:21PM (#38580454) Journal

      I think they released this information to show that other offerings were bogus.

      I've been interested in a solar cell that could run my phone in even very cloudy weather. I also wanted it to charge/run a radio, a flashlight and recharge some batteries though not all at once. It would cost between $200-$300US for one that can run and charge my phone or do any of the other individual tasks and be rugged enough for my needs.

    • by game kid (805301)

      They considered roping the solar panel duck to the phone, but tape was cheaper and more effective so they went with that.

    • Re:So basically (Score:4, Insightful)

      by steveha (103154) on Tuesday January 03, 2012 @09:43PM (#38581018) Homepage

      I guess you are being funny, but if you read TFA you will find that they shipped prototype phones to volunteers. For example, their volunteer in Kenya works as a security guard and was well able to get sunlight for his phone (lots of sun plus he sits in one place a lot so he could just leave the phone in the sun a lot).

      Basically this project just cost Nokia the cost of knocking out a few prototypes and shipping them. I'll bet their engineers had an idea about how well it would work, but now that they have tried it, they have data on exactly how well it does or doesn't work.

      steveha

    • with a solar panel duct taped to the back of it?

      FTFY

  • But the solar panel will be much bigger than the phone. Solar power has always been quite weak, especially for something as power hungry as a cell phone. The fact that solar is going so far today is only the result of large, well-designed panels.
    • by mattack2 (1165421)

      Solar power has always been quite weak

      Except that solar calculators work(ed) quite well, even on indoors light. Yes, I realize they presumably used an incredibly low amount of power compared to a phone, and I agree with most of the other comments (e.g. a phone is usually in one's pocket).

      Still, it seems to me that keeping a phone on standby is far better than nothing.. It at least would increase the time between recharges.

  • A combo solar USB battery/charger: http://shop.philips.co.uk/store?Action=DisplayProductDetailsPage&Locale=en_GB&SiteID=rpeeub2c&productID=202504800 [philips.co.uk]

    So, you can charge the battery via USB or via the solar panel. Now, how long it takes to charge the battery . . . it might help if you live some place where there is a lot of sunlight . . . like on Mercury.

    I used something similar a while back on vacation in Portugal in summer . . . the solar charge of a whole day wasn't able to top off my cell ph

  • by hipp5 (1635263) on Tuesday January 03, 2012 @08:22PM (#38580464)
    I mean, if I can have this in combo with a battery that would be moderately cool. If it maintained standby power and I only drained from the battery when actively using the phone I'm sure it would reduce the frequency I'd have to recharge. Surely that's worth something.
    • by sfm (195458) on Tuesday January 03, 2012 @08:37PM (#38580576)

      Unfortunately, letting the phone sit on the dash of your car while
      charging causes it to heat up, significantly reducuing the life
      of your lithium battery. A better choice is to use an external
      solar panel to ship power ot your phone (which is tucked safely
      away, out of direct sunlight). So have we come full circle on this ?

  • Rather than making solar-powered phones, Nokia have pretty much solved the problem already by making simple high-efficiency phones like the 1280, which can run for 2 weeks between charges.

  • by guttentag (313541) on Tuesday January 03, 2012 @08:27PM (#38580520) Journal
    This explains why they kept getting closer and closer to windows. Maybe now that they've realized this isn't the way to go they can get back on track.

    rimshot

    Maybe if they took the phone outside they'd get better results. All the imperfections in the windows are probably cutting into the amount of actual power the device gets.

    rimshot

    Thank you, I'll be here all week. Try the veal.
    • by game kid (805301)

      I thought they should use the Track OS too but they didn't listen.

    • by jjoelc (1589361)

      Maybe if they were allowed to OPEN the WINDOWS...

      Thanks folks, I'll be here all week... Don't forget to tip your waitress!

  • by Shavano (2541114) on Tuesday January 03, 2012 @08:29PM (#38580536)

    You can't get more than 100mA of charging current out of a collector on the back of a cell phone.

    With a typical battery capacity of 2700 mAh, that means it would take 27 hours of vertically incident sunlight to charge your battery.

    Good luck with that.

  • Only lacked an exploding battery, and, well, trying another approachs, like wearable solar charging clothes (could be the next fashion, or at least for cellphones for soldiers, police or other professions with uniforms), or taking energy from other sources (heat from body or environment, sweat, walking/running, or even heartbeats)
  • by not_surt (1293182) on Tuesday January 03, 2012 @08:35PM (#38580568)

    Like many in the developed world I carry a considerable surplus fuel stockpile on my abdomen which it would be nice (and perhaps healthy) to take advantage of.
    Maybe a combination if an in-body blood sugar energy harvesting [wikipedia.org] rig and inductive charging coils on each hip? If your fuel stockpile is running low then make it a solar charging rig with a symbiotic algae/cyanobacteria in the skin to produce sugars from sunlight.

    • Or you could always use pee [bbc.co.uk] to generate your own power. You could stick some electrodes into your bladder, or if you're the squimish type, you could just do it the traditional way and refill your phone with fresh pee every 6 hours.

  • by Megahard (1053072) on Tuesday January 03, 2012 @08:45PM (#38580628)
    A nuclear powered phone.
    • Re: (Score:2, Funny)

      by Anonymous Coward

      solar powered flashlight

    • Solar energy is nuclear energy...

      • Gravitational confinement fusion - the only kind known to work so far. It's somewhat lacking in shielding though. Even from 149.6 million km away, it will still kill you several ways if you don't have the equivalent of 10 meters of water or 4 meters of rock to protect you.

    • Oh.

      I was hoping they would develop a solar powered torchlight!

  • by bmo (77928) on Tuesday January 03, 2012 @08:49PM (#38580658)

    They physically tested the phone at the equator and in Sweden and that was the only way they could figure out that the solar flux would be higher at the equator?

    Like, someone couldn't sit down at a desk with a calculator and trig it out and find out how much exactly the phone would get at 50 degrees N latitude as opposed to 0?

    Someone fucking hire me. I will figure this shit out for you. I won't even need to be flown out anywhere (though southern Italy would be nice). I'll just crunch out the numbers and they will be accurate and a lot faster than what Nokia got their results.

    --
    BMO

    • Re:Wait what? (Score:5, Insightful)

      by JoeMerchant (803320) on Tuesday January 03, 2012 @09:14PM (#38580828)

      They physically tested the phone at the equator and in Sweden and that was the only way they could figure out that the solar flux would be higher at the equator?

      Like, someone couldn't sit down at a desk with a calculator and trig it out and find out how much exactly the phone would get at 50 degrees N latitude as opposed to 0?

      Someone fucking hire me. I will figure this shit out for you. I won't even need to be flown out anywhere (though southern Italy would be nice). I'll just crunch out the numbers and they will be accurate and a lot faster than what Nokia got their results.

      --
      BMO

      Somebody sat at a desk with a calculator and trig'ed it out long before people went on the road to do the testing. Being Nokia, they may have had people in the field who did not have to travel, or, they just sent the engineers on a perk trip to do ground truth.

      It isn't really tested until you've done the ground truth.

      • by PCM2 (4486)

        It's possible that they calculated that such a device might possibly be useful to people living in adverse conditions, who might be willing to sacrifice normal use cases (e.g. leaving it on the dashboard of the car when not in use, instead of carrying it in a pocket) if it meant they'd have access to a phone. So they sent it to some people who might be willing to try it, to see if it would actually work out that way. It didn't.

  • I'd think they'd be better off making a snazzy clothing accessory and marketing it with the phone instead. Solar vest, maybe? Vests are just waiting for an excuse for a comeback. There are already backpacks with solar panels, but those aren't really practical for non-students.

  • by jginspace (678908) <[moc.oohay] [ta] [ecapsnigj]> on Tuesday January 03, 2012 @09:59PM (#38581134) Homepage Journal
    This research was killed by several three-letter agencies who shiver at the prospect of people not actually carrying their phones ON THEIR PERSON. Those hellfire missiles aren't cheap and they want them to hit those nasty mujahadis when they're least expecting it - having the missile crash through the roof - not blowing the poor bugger's Nokia up while it's sitting on the porch and he's sitting in the outhouse.
  • we'll have the ability to collect solar energy on a large scale and transfer it to some sort of storage device that attaches to the phone . . .
  • It probably can't charge it for daily use on a phone-sized solar panel, though. It'd still be nice to have some solar panels on the phone so that you could get SOME talk time after 8 hours of charging if you were in the desert or something...

    I'm sure if you have a backpack (or larger) charger, you'd be able to charge your phone just fine...

  • typical slashdot post with title suggesting nokia concluded "the sun can't charge your phone" the article says it can; just not in very practical way yet. As the article concludes: Reasonably good results were also obtained when the tester was able to carry the phone while moving around outdoors, for instance in a holder around his neck. However, this isn’t necessarily the most stylish or convenient arrangement, and another solution is needed. So it is more saying "the sun can't in a practical way
  • by Tanuki64 (989726) on Wednesday January 04, 2012 @05:51AM (#38583342)

    Just invent a folding solar cell panel. Usually stored in the phone, while charging unfolded to a size of at least 1m^2.

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