Nokia: the Sun Can't Charge Your Phone

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Nokia: the Sun Can't Charge Your Phone

Posted by Soulskill on Tuesday January 3, 2012 @01:02PM 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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it should have been by bugs2squash · 2012-01-03 13:05 · Score: 5, Funny

a tablet then

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Nullius in verba
1. Re:it should have been by davester666 · 2012-01-03 14:48 · Score: 4, Funny
  
  or switch to Intel chips. I keep reading how Intel is just about to ship a really low-power chipset for cell phones in just a few months.
  Of course, I've been reading this for about 5 years now.
  
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2. Re:it should have been by Anonymous Coward · 2012-01-03 17:26 · Score: 5, Funny
  
  Wait just a second here. My Sun Blade 2500 workstation charges my phone just fine, thank you very much. All I have to do is plug the cable into the USB port and It Just Works. What a stupid, misleading article title.
Why did they think this would work? by TWX · 2012-01-03 13:06 · Score: 5, Insightful

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.

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Do not look into laser with remaining eye.
1. Re:Why did they think this would work? by bmuon · 2012-01-03 13:10 · Score: 5, Insightful
  
  No idea. Mechanical energy -motion and/or sound waves- seems a more likely source of power for a phone.
2. Re:Why did they think this would work? by timholman · 2012-01-03 13:14 · Score: 5, Insightful
  
  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."
3. Re:Why did they think this would work? by viperidaenz · 2012-01-03 13:22 · Score: 4, Informative
  
  You can get 0.5W panels about the size of a smart phone for $2.00. 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.
4. Re:Why did they think this would work? by digsbo · 2012-01-03 13:24 · Score: 5, Interesting
  
  No need. Have you used a Nokia low-end phone lately? They can go two weeks without a charge. Seriously. I just lent a friend a 2320 for use while in the USA and it lasted a full 15 days. And yes, they made calls on it! Amazing.
5. Re:Why did they think this would work? by Korin43 · 2012-01-03 13:33 · Score: 3, Interesting
  
  Would it not make sense for them to still use this idea to some extent, though? Put some solar panels on the phone just to give that extra little bit of battery life.
  It's probably cheaper and more effective to just give it a bigger battery.
6. Re:Why did they think this would work? by khallow · 2012-01-03 13:48 · Score: 5, Interesting
  
  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.
7. Re:Why did they think this would work? by ewieling · 2012-01-03 14:01 · Score: 5, Funny
  
  My Motorola V3M has the battery life of a smart phone and the features of a dumb phone. Worst Phone Ever.
  
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  I really shouldn't have used someone else's email address for this account.
8. Re:Why did they think this would work? by GreatBunzinni · 2012-01-03 14:22 · Score: 4, Interesting
  
  ...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.
  
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9. Re:Why did they think this would work? by Jarik+C-Bol · 2012-01-03 14:24 · Score: 5, Insightful
  
  the same way self winding watches work. Your arm is not a windmill either. In this case, a small magnet, in a tube, wrapped in a coil, such that when the user walks, the magnet slides from one end of the tube to the other, and back again. The real trick is to figure out how to arrange this little setup to maximize the number of times the process occurs, with minimal movement.
  
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10. Re:Why did they think this would work? by Goaway · 2012-01-03 14:53 · Score: 3, Insightful
  
  You're thinking of this as "walking up 14 flights of stairs" but that is entirely misleading.
  Since you said "small hand crank", what you should imagine is this: Tie a rope to a person, then use a small hand crank to winch them up to the 14th floor of a building.
  It probably doesn't sound as good any more.
11. Re:Why did they think this would work? by Anonymous Coward · 2012-01-03 15:01 · Score: 3, Informative
  
  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.
12. Re:Why did they think this would work? by Anonymous Coward · 2012-01-03 15:21 · Score: 3, Funny
  
  WINDMILLS DO NOT WORK THAT WAY. GOOD NIGHT.
  Morbo feels sorry for the idiots who implemented the Slashdot filter.
13. Re:Why did they think this would work? by trawg · 2012-01-03 15:33 · Score: 3, Interesting
  
  Not really related, but I recall John Carmack recently posted on Twitter saying that a cell phone will use less than $1 of grid electricity over their lifespan (based on this calculation).
  Interesting insight into how little power a cell phone uses compared to other devices!
14. Re:Why did they think this would work? by quacking+duck · 2012-01-03 16:59 · Score: 3, Informative
  
  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.
15. Re:Why did they think this would work? by nedlohs · 2012-01-03 17:31 · Score: 4, Informative
  
  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.
16. Re:Why did they think this would work? by Grishnakh · 2012-01-03 18:10 · Score: 3, Interesting
  
  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.
17. Re:Why did they think this would work? by bemymonkey · 2012-01-03 19:38 · Score: 3, Interesting
  
  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
  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.
So basically by Deathnerd · 2012-01-03 13:08 · Score: 5, Funny

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?
1. Re:So basically by mrmeval · 2012-01-03 13:21 · Score: 3, Interesting
  
  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.
  
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2. Re:So basically by steveha · 2012-01-03 14:43 · Score: 3, Insightful
  
  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
  
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Nokia's Been Researching Solar Power? by guttentag · 2012-01-03 13:27 · Score: 4, Funny

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.
My cocktail napkin agrees by __aaltlg1547 · 2012-01-03 13:29 · Score: 3, Informative

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.
Look closer to home by not_surt · 2012-01-03 13:35 · Score: 5, Funny

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 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.
Re:But does it extend battery? by sfm · 2012-01-03 13:37 · Score: 3, Informative

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 ?
On to the next idea by Megahard · 2012-01-03 13:45 · Score: 5, Funny

A nuclear powered phone.

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I eat only the real part of complex carbohydrates.
Re:Wait what? by JoeMerchant · 2012-01-03 14:14 · Score: 4, Insightful

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.
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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.
Sound waves don't carry enough power by Anonymous Coward · 2012-01-03 14:20 · Score: 3, Informative

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 the neighbours three doors down overhear your latest 'performance review').
I can't see that charging a phone any time soon. 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.
As an aside, the very low power levels associated with actual sound waves is why most stereos / home theatre setups are grossly overpowered. I have a 65w per channel amplifier, and with some custom-built high-sensitivity speakers, I've never turned it up much above -20dB, and that's painfully loud. That's less than 5w per channel...
(Note: really low-frequency *does* require a lot of power, as it needs to move a lot of air to get the same sound pressure level, which is why subwoofer amplifiers are often rated at 5-10 times the main amp - my sub has a 450w amp in it, for example)
Thinking cap on... by fyngyrz · 2012-01-03 15:41 · Score: 4, Funny

Hmmm..... deep vee cleavage tops for chicks.... glittery solar cell appliques for their breastesess... motorized bras that cause nipples to auto-track the sun when the sun is in front of said chick... woven golden wires leading to cellphone pocket like a necklace...
PROFIT!
Wait, did I say that out loud?

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