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Education Handhelds Power News

Tablet Prototype Needs No External Power Supply 110

timothy writes "I'd like to see computing devices with no need for an external power supply — an e-book reader, a general knock-about PDA, a phone — all kinds of things. But there's a certain heart-strings appeal to such a computer intended as an educational tool for precisely those kind of places where basic infrastructure (like the provision of electricity) is a stumbling block. Perhaps built-in solar makes more sense, in more places, than the hand-cranked power the OLPC project ended up dropping from their laptops-for-kids program."
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Tablet Prototype Needs No External Power Supply

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  • First Post (Score:2, Funny)

    by Anonymous Coward

    I'd like to say it was from a PC with no outside power supply, but I can't. I don't think I can get the generator and bicycle rigged up in time.

    • Re: (Score:2, Insightful)

      by operagost ( 62405 )
      Stop being lazy, Gilligan! Mr. Howell wants his blender working by this afternoon, and the coconut smoothies won't make themselves!
  • Best feature (Score:1, Interesting)

    by Anonymous Coward

    The best thing about built-in solar and no external supply is that it would force users to regulate their usage time.

    • Re: (Score:2, Funny)

      by SnarfQuest ( 469614 )

      I'm building one that runs on hydro power, but it's a little big with the swimming pool attached to it.

    • I'm not really so sure that's a concern in the places where there isn't even an infrastructure for electricity. Those kinds of places tend to be extremely poor countries (or just areas) where the people including children have to work all day in fields or factories if they want to be able to eat that day. We're not exactly talking about kids lazing on the couch all day long playing plants vs. zombies for 8 hours and shouting at their mother because they want McDonalds for dinner tonight.

      Even if it were
    • Re:Best feature (Score:5, Insightful)

      by grcumb ( 781340 ) on Monday November 15, 2010 @06:22PM (#34236966) Homepage Journal

      The best thing about built-in solar and no external supply is that it would force users to regulate their usage time.

      Heh, yeah.

      Why is it that people think solar power works better in the tropics than elsewhere? Do they think we don't have clouds?

      I live and work in a Least Developed Country, and for years now I've watched as, time and again, people take a look at the power generation problem and say, "SOLAR FTW." Then they discover that it rains much of the year, that there are mountains which tend to reduce the hours of direct sunlight, as well as a smattering of rain forest overhead and, to top it all off, we occasionally get hurricanes, which leave the place without power at exactly the time we need it most.

      Bottom line: Every location has its own unique power generation challenges. In some places, wind is the answer. In others, micro-hydro. In others a diesel generator and a big battery is the only reasonable answer. For most, it's a mix of several approaches. I have yet to see a single community in the entire country for which solar is the entire answer.

      So to technology makers, I can say only this: PUT A FUCKING PLUG IN IT. The solar panel is optional; the plug is not. You don't -you can't- know what form of power generation is going to work. So leave that problem for others to solve. Just make it low-enough-power that it's not going to cost more to run than it is to purchase.

      • by Moryath ( 553296 )

        This is why shake/crank is perhaps the best. As long as someone has enough energy to move, they have the energy to operate. And as long as a shake/crank device has an external plug to power other things, you can make it run.

        The worse part today, however, is how much power devices use.

        - Backlit screen? Better be switchable. The screen needs to be readable in sunlight too, so that switching the backlight off actually saves power usefully.

        - Processor? The slower, the better. Yes, that's counterintuitive, but p

        • Work done also scales linearly with clock speed. Reducing clock speed is beneficial only so far as it allows the CPU to run at lower voltage. Modern CPUs are generally pretty good with C1_power/C0_power, but there is room for improvement. I contend that the key to reducing power consumption is to reduce unnecessary wakeups. These statistics can be viewed in Linux with the powertop utility.
      • by geekoid ( 135745 )

        Actually, solar panels will work with cloud cover. Take a solar power calculator outside, and it will still work.

        And wind is almost never the answer.

  • In this house, we obey the laws of Thermodynamics!

    No external power supply they say, well then, either they finally created a perpetual motion machine, or they're getting the energy from some external power supply.

    • Re: (Score:2, Offtopic)

      In this house, we obey the laws of Thermodynamics!

      No external power supply they say, well then, either they finally created a perpetual motion machine, or they're getting the energy from some external power supply.

      Excellent Simpsons reference [wikiquote.org] from episode [2F19] The PTA Disbands.

      • You realize that Homer Simpson has said everything, right? And that it's no longer possible to express a thought without quoting or paraphrasing Homer Simpson? Probably even this one...
        • Well, we can use South Park for this one (The Simpsons already did it)

        • You realize that Homer Simpson has said everything, right? And that it's no longer possible to express a thought without quoting or paraphrasing Homer Simpson? Probably even this one...

          The second law of Godwyn?

        • You realize that Homer Simpson has said everything, right? And that it's no longer possible to express a thought without quoting or paraphrasing Homer Simpson?

          'Then there are some things you never hear. That makes sense, some things you never hear. You never hear this, "dad, you really ought to drink more."
          Here's something you don't hear too often. "Do what you want to the girl, but leave me alone."
          Here is something no one has ever heard ever. Ever. "As soon as I put this hot poker in my ass, I'm going to chop my dick off." You know why you never heard that? Right! No one ever said that. Which to me is the more amazing thing; no one ever thought to say that befor

          • Well, maybe he hasn't said any of that on camera... but we only see a small window of his life. Do I have to explain everything?

            PS - that was some funny shit, right there. Thanks for the laugh.

    • Or a miniaturized RTG battery, with an half-life of 87.7 years you should be ok !

      • I did a little research
        the best miniature RTG are currently producing 300 W cm3 they to so at 350mV so a 10cm3 device could give 3mW you could use this to charge an ultra cap and power a device like an e Ink reader for about 80 years |

        • and slashdot eat my micro symbol !

        • by mirix ( 1649853 )

          The thermocouples wear out before the decay source does.

          And then you run into problems like people selling the lead shielding for scrap, and leaving the pu or sr90 or whatnot to rot. And this is with big, expensive ones. Do not want.

    • Re: (Score:3, Funny)

      either they finally created a perpetual motion machine

      Those have actually been around for ages.

      See: Children

      • Tell that to Europe and Japan.

      • Those have actually been around for ages.

        See: Children

        Pft. I keep hearing that, but, after several rounds of controlled experiments, I've found that the reality fails to live up to the hype. You stop feeding the little bastards for a measly week, and they get all weak and useless on ya. Never mind what happens when you take away water.

    • RTFA (Score:1, Flamebait)

      by copponex ( 13876 )

      It uses a tiny solar cell, like a calculator. If you have some form of light, you have a computer.

      Palem says the I-slate is the first of a series of electronic notepads being built around a new class of low-energy-consumption microchips under development with Switzerland's Center for Electronics and Microtechnology. The team says the chips will allow the I-slate to run on solar power from panels similar to those used in hand-held calculators.

      If you aren't going to read the articles posted to slashdot, may I

      • by Kenja ( 541830 )
        Solar cells dont work without an external source of power.
        • RTFC (Score:5, Insightful)

          by copponex ( 13876 ) on Monday November 15, 2010 @05:15PM (#34236374) Homepage

          This perfectly illustrates why the nerd pedantry is lonely, angry, and ignored. People with lives understand "requires no external power supply" to mean "doesn't have to be plugged in." Instead of accepting this, a few people have decided to ignore the hard work of these people to bring revolutionary educational tools into the hands of poor rural children, and quibble about thermodynamics.

          From the top and bottom of my heart, please fuck off. The adults are doing useful things. Leave them to it.

          • :S My nerd pedantry went the opposite way with it. I assumed that they meant no external power supply. As in, no brick midway down your laptop cord. And I thought wow, what a prissy bitch. Putting a large heat generator inside the computer when it doesn't have to be is stupid. Just leave the damn thing as part of the power cable and get over it.

            Though they need to have the brick-laptop cable be standardized and detachable. They break all the time and you generally have to replace the whole brick to fix it
            • by Cylix ( 55374 ) *

              The cables frey and wear from being improperly stored.

              I've seen many people tightly wind the cable around the brick and put a good deal of tension on the portion which is attached to the power brick. I've successfully trained several sales people to carefully wrap their cables up leaving a good deal of slack as to not stress the cable. That little nugget kept them from replacing their bricks until the end of life on the laptops. It had the secondary benefit of teaching them to take care of their equipment a

              • Even so, there is a reason when you buy a laptop from some place like Dell the adaptor isn't under warranty. Because they break constantly! And replacements are around 50 bucks. If the cable were detachable that would lower cost of replacement to ~$5. Or if they were standardized (just the plug) then costs for the whole adaptor would still drop, maybe to $35 or $25.
          • by Osgeld ( 1900440 )

            call me when they exist in mass

          • Re: (Score:3, Insightful)

            by wondafucka ( 621502 )

            This perfectly illustrates why the nerd pedantry is lonely, angry, and ignored. People with lives understand "requires no external power supply" to mean "doesn't have to be plugged in." Instead of accepting this, a few people have decided to ignore the hard work of these people to bring revolutionary educational tools into the hands of poor rural children, and quibble about thermodynamics.

            From the top and bottom of my heart, please fuck off. The adults are doing useful things. Leave them to it.

            Although I wholeheartedly agree with you, I thought that posting on slashdot _was_ leaving them to it. You think anyone who actually gets stuff done reads this stuff? (ducks)

          • You're the one who needs to fuck off. Needing the external power supply, the sun, means this thing will be mostly useless for months in 3rd world places such as my wife's country while it's cloudy and/or raining buckets. But something with a 220VAC 50 Hz plug would function in most schools.

            Reality is a bitch, and technical and engineering types deal with reality.

            • by copponex ( 13876 )

              Reality is a bitch, and technical and engineering types deal with reality.

              It's a good thing you're not an engineer.

              Photovoltaics do not require direct sunlight, or specifically sunlight at all, in order to function. That's why calculators work inside of buildings without windows. As for this device, I don't know how much power it requires, but I wouldn't be surprised if they designed it so it would operate with the power provided by a kerosene lamp or other type of fire.

              Again, please fuck off, and leave all that tough thinking to the adults. Your childish hubris and adolescent la

              • I am an engineer, and moreover note the pictures of this "I-Slate" prototype being shown on the web are currently running on wired DC power.

                Reality is indeed a bitch, child

          • Thank you for putting that more thoughtfully than I would have. Pity I have no mod points.

      • Most intelligent beings consider our sun, Sol, to be the largest external power supply we have access to.

        It, and other stars like it are in fact as far as we know the only sources of usable power that exist to humans.

        Without sunlight there is no fossil fuels, no hydro power, obviously no solar cell/boiler power. Even nuclear reactors get their power from things born during the death of larger stars.

        If you have a solar cell, you are using an external power source and wireless transmission, but none the less

    • I assume the idea is a Kindle-y tablet with a battery inside (like most tablets) and a solar panel on the back (unlike most tablets). To charge the thing you just lay it down outside, with the solar panel pointed up.
    • Re: (Score:3, Insightful)

      Okay, seriously, why does pedantry like this get modded up? Anyone who takes even a cursory glance at the summary understands what "no external power supply" means in this context, and it's a perfectly good phrase for what they're describing. There was nothing insightful about OP's comment, just oh-look-how-smart-I-am snark.

    • Interesting. Theoretically, energy (actually, an increase in entropy) is only required to discard information, ie clearing memory. Whilst this does limit the actual "computation" possible, a single-state machine can still contain a lot of information. Fair enough, nothing will change without a power source, but that's just an interface problem....
    • Sure, if you define "external power supply" as an "external power source".

      Not if they defined "external power supply" as something you need to plug in/or replace on the device. And hence a bog standard solar panel would remove the need for one.

  • The Sun (Score:2, Insightful)

    by xerio ( 1001881 )
    Wouldn't that kind of count as an external power supply?
    • by blair1q ( 305137 )

      And an unreliable one.

      Only works a few hours a day, and only on days it's not raining.

      • by Nadaka ( 224565 )

        Sounds like my brother.

      • by Dan541 ( 1032000 )

        Plus it requires us to leave the basement.

        • by mcgrew ( 92797 ) *

          Very few have left the basement, and most of them were nerds. It's damned hard to leave the basement, what with the gravity well and all. At least we have that nice fusion lamp and the reflector night light.

      • by geekoid ( 135745 )

        The Sun ism incredibly reliable. It's the Earth that causes those issue... and it does so reliably.

        Maybe some day someone will figure out how to store energy during the night. Also, maybe someone will let you know that solar works on cloudy days. Not as well but it does work. What the means is when deciding how many sq. Meters of panels you need, you don't base it on the sunniest day.

        Assuming you're using panels. You could use solar thermal with a lens to focus the light onto the tube carrying the sodium.

  • But there's a certain heart-strings appeal to such a computer intended as an educational tool for precisely those kind of places where basic infrastructure (like the provision of electricity) is a stumbling block.

    That appeal will remain just that: An appeal, which sadly delivers no results in most cases.

  • Given that they might be flooded with used phones and probably first-gen smartphones soon, perhaps something that can charge USB phones would be in order...

    http://www.google.com/search?q=bicycle+USB+dynamo&hl=en&tbs=shop%3A1&aq=f [google.com]

    Would love to play with some of that stuff, but those currently cost more than my cheap-ass bike :-P Should be neat if they could develop some cheap dynamos to distribute where they would need it, though. They also have bikes with full kickstands that elevate the rear

  • Why embedded? (Score:5, Insightful)

    by Dan East ( 318230 ) on Monday November 15, 2010 @05:20PM (#34236416) Journal

    It doesn't make much sense to me to embed mechanical / solar / whatever power sources directly into these sorts of products. This is especially true for mechanical power sources, like a crank. That should be in an extremely ergonomic external form factor that a person can operate comfortably, without risking dropping their laptop / tablet, or accidentally flinging it across the room.

    Same with solar. That needs to be in a waterproof form factor that can be left laying on the ground or roof in the rain without being destroyed.

    A family with two or more devices could get by with just one solar charger, or better yet, one solar and one mechanical, to give them more charging options.

    When I was a kid I had one of those little generators that was rotated by my front tire, which powered a little headlight. Something like that could be used with any bicycle to generate relatively massive amounts of power (compared to a hand crank). A very simple stand (home made or otherwise) to get the back tire up off the floor and they're ready to do some serious charging.

    • by lwsimon ( 724555 )

      Professor? Is that you?

    • by blair1q ( 305137 )

      Or we could dam up the river and attach a wheel to the falling water and hook up some rotating permanent magnets and...

      • Or we could start cutting down and digging up flammable substances to burn in a boiler which creates steam to turn a wheel that are attached to some rotating permanent magnets and...

    • I agree, don't embed these things. If they're separate, they can power multiple devices, thus bringing the overall cost down (needs less power gen devices per consumption devices). For example, the merry-go-round power generators that I heard about some people installing a couple years ago is a brilliant idea that can power quite a bit for cheap.
  • Solar Calculator (Score:1, Insightful)

    by Anonymous Coward

    I had a solar powered calculator back in the early 90's. You can't tell me we don't have low powered computers today that do more than that on nothing more than the sun. ...so where are they?

  • My father's TRS-80 model 100 ran for about 50 to 100 hours on a set of off the shelf AA batteries.

    If you assume the device will be "hopelessly" obsolete in 2 years, or half of them will be destroyed in accidents in 2 years, and maybe it only gets used a couple hours per week, and a modern device with a crude enough display technology might only draw a tenth the power, maybe a very large couple pound lithium battery could power a tablet for its useful life.

    • If you assume the device will be "hopelessly" obsolete in 2 years

      For people with more money than they should, possibly. For everyone else, and especially in developing countries, stuff is used until it breaks, then repaired and reused for some years more.
      While repairing tablets is "somewhat" more difficult than boomboxes, two years is nothing. In many cases, computers used in those places are already more than two years old when they get there.

  • by joeyblades ( 785896 ) on Monday November 15, 2010 @05:50PM (#34236720)
  • hrm (Score:5, Interesting)

    by Charliemopps ( 1157495 ) on Monday November 15, 2010 @05:57PM (#34236790)
    I think this is rather typical of the western world. The idea that 3rd world countries do not have any access to electricity is just silly. I've recently been to the heart of Ethiopia to adopt a child and if there's one thing they had plenty of it was electricity. Not a lot of food, or clean water... Gas was $8 a liter and they were living in thatched roof, mud huts. But there was electricity all over the place. The rats nests of electrical wire strung, sometimes, from tree to tree was a testament to this. I have no idea how the entire country hadn't burst into flame already but their electrical grid did fail from time to time... but not nearly as often as you'd expect it to. I have to admit I have a lot of respect for whomever keeps the electricity flowing, they must be a McGuiver style genius.

    What they did lack was Linux. Every PC I saw there (and there were very few) had a pirated copy of WinXP on it, with the WGA notice popping up constantly and was filled with Malware. Had their dialup modems been able to connect at any speed greater than 9k I would have fixed it for them but in the end I just gave up.
  • What about a computer that is powered by inducing current in wires by sliding a set of magnets back and forth?

    Configure the magnets and wires such that they resemble an abacus and presto: Computer powered computer.

    Up next:
    A vehicle powered vehicle (electric bicycle that charges when you pedal),
    Toast powered Toaster (burns bread to heat bread),
    etc...

  • by steveha ( 103154 ) on Monday November 15, 2010 @09:50PM (#34238470) Homepage

    Perhaps built-in solar makes more sense, in more places, than the hand-cranked power

    Perhaps it does, perhaps it does! If, that is, you can build the device such that it can run off of built-in solar. That's the real trick, isn't it.

    A simple four-function calculator trivially can run of a little photocell, and this has been true for decades. So why didn't OLPC simply put a little photocell on the XO-1? Because a little cheap photocell doesn't produce anywhere near the needed power needed by an XO-1.

    And, the hand-cranked power is a particularly irritating straw man. A long, long, time ago, when OLPC was just an idea, they thought about a hand crank, and even made a mockup of what it might look like. But it was never made. Reasons: 0) some kids live in places with a decent electrical grid, so there is no need to add the cost of a generator to every single laptop; 1) an external generator can be trivially replaced if it breaks, without the laptop itself needing to be repaired; 2) a crank built-in to the laptop adds mechanical cranking strain on the laptop, necessitating the laptop being made sturdy in otherwise-needless ways; and 3) little kids are not known for their arm strength, so a generator that could be operated by leg muscles was deemed better. OLPC announced that a pull-cord generator would be the human powered generator, but as far as I can tell from a few quick Google searches just now, the pull-cord generator is still vapor.

    I recently sent my XO-1 to India for use by the Bharti Integrated Rural Development Society [birds-india.com]
    (B.I.R.D.S.) and I looked into a solar array for it. I found one for about $200 that should operate an XO-1 continuously and charge the battery in about an hour. I also found lots of other solar arrays that cost way more than that. So, the most affordable solar array I found cost more than the XO-1. As I understand it, the B.I.R.D.S. school has electrical power only when they run their generator, which is a few hours a day, so my hope is that the XO-1 will be useful just with the generator power. (Conveniently, the power supply on an XO-1 accepts any AC from 100 to 240 Volts, at 50 or 60 Hz, so they should be able to just plug it in with a plug adapter.)

    Note that TFA says "...the I-slate is the first of a series of electronic notepads being built around a new class of low-energy-consumption microchips under development...". So, one of the reasons the OLPC XO-1 isn't powered with a little solar array is that it was developed half a decade ago, and the new ultra-low-power chips are, well, new.

    Isn't it enough to say "This is a cool new technology and I'm excited about it" rather than talking about how much better it is compared to a half-decade-old technology?

    P.S. I put an 8 GB flash card in the SD card slot on the XO-1. On the card I put a copy of Wikipedia for Schools [schools-wikipedia.org], which takes up about 4 GB; then I put some health and medical books [hesperian.org] and a bunch of classic fiction books (for students to read when studying English). I updated the OS on the OLPC to the latest build, and installed a typing tutor program (Typing Turtle) from Sugar Labs [sugarlabs.org]. I found a public-domain copy of The Elements of Style [bartleby.com] and a few other free textbooks. Finally, I put a few books on Python Programming. I haven't had any email back from B.I.R.D.S. telling me anything, so I have no idea how it's working out.

    I have to say, an XO-1 loading books straight off an SD card is a pretty nice book reading platform! And with the backlight off, to read books in monochrome, battery life should be pretty good. I'm hoping they will find the XO-1 to be useful.

    steveha

  • Why isn't the back of the kindle a solar panel?

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