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Nokia: the Sun Can't Charge Your Phone
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."
a tablet then
Nullius in verba
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.
Do not look into laser with remaining eye.
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?
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.
You can buy some things that are similar to what you're talking about already. I've actually got a kinda small one that won't do much while using my phone with like everything on, but if the phone's sitting idly, it'll charge it pretty well. This one's not quite as much as you're talking about--it does have a battery that it puts the charge into, but it's actually pretty small and really only meant to keep the charge off of the panel more consistent (makes a light more solidly on as opposed to flickering on a very similar panel without the battery; this is just my very limited understanding of it, so I could be off on why they have a minimal battery on the thing, but that's the way the sales guy was describing it to me when I bought it). However, if they even started selling these with phones, that would be pretty cool in itself (though I think it's more of a niche market--most people I know don't really charge the phone in sunlight very often...)
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.
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.
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.
A nuclear powered phone.
I eat only the real part of complex carbohydrates.
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
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)
Right next to your head?
I've got one. Its a solar panel with charge control and an internal battery. It can be placed in direct sunlight and charged in about a day. Once charged, it will charge anything with a USB power plug from its internal battery.
I'd guess that most phones spend most of their time deep in someone's pocket. This charger can be left where the sunlight is best. Also, its somewhat larger than a cell phone. Building the PV cells into a phone is a compromise between small collector area and an oversized phone.
Have gnu, will travel.
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.
Once charged, it will charge anything with a USB power plug from its internal battery.
Anything? Remember it's Nokia we're talking about here. They were very slow in getting into the USB-charging game and even now their USB chargers require some kind of circuitry to negotiate the connection (like on the USB port of a laptop) - you can't just plug them into a dumb USB port.
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?
I've fallen off your lawn, and I can't get up.
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 charge your phone right now and improvements are needed before it's practical" I'm sure we'll see improvements in phones to become more energy efficient & better solar panels which may make this more practical in the future.
Just invent a folding solar cell panel. Usually stored in the phone, while charging unfolded to a size of at least 1m^2.