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Carbon Nanotube Towers Could Increase Solar Power

Vict0r writes "Researchers at the Georgia Tech Research Institute have recently demonstrated a way to grow carbon nanotubes in towers. The article also discusses applications for solar cells." From the article: "Reflections off the Gothamesque towers would provide more opportunity for each photon of sunlight to interact with the p/n junction of the cell. That would increase the power output from PV cells of a given size, or allow cells to be made smaller while producing the same amount of power."

141 comments

  1. Even better by nizo · · Score: 4, Funny
    Reflections off the Gothamesque towers would provide more opportunity for each photon of sunlight to interact with the p/n junction of the cell.

    We need mirrored solar cells. Just set them up so they reflect the light back and forth between all the cells for a neverending unlimited source of energy!

    1. Re:Even better by Game_Ender · · Score: 2, Informative

      That would be cool if only that pesky photo din't get absorbed ;)

    2. Re:Even better by PitaBred · · Score: 4, Funny

      "In this house, we obey the laws of thermodynamics!" - Homer S.

    3. Re:Even better by hawkbug · · Score: 1

      Obviously, you'd have some energy loss.... but mostly, why wouldn't this work? I'm not scientist or electrical engineer, but I would think you could point a light beam from the sun using mirrors into a chamber full of mirrors and that also had solar panels in it.........

    4. Re:Even better by Umbral+Blot · · Score: 3, Informative

      Because solar panels take energy from the light to produce electricity. You can only extract so much energy from a given photon.

    5. Re:Even better by databyss · · Score: 1

      Once the light comes in contact with the solar panel, the light is absorbed. Why rish wasting energy reflecting it when you can just absorb it on first contact?

      --
      Hmmm witty sig or funny sig? Maybe elitest techy sig!
    6. Re:Even better by Issue9mm · · Score: 4, Informative

      Because, as is the point, the solar panels ABSORB the light, not reflect it back. I don't have any hard numbers, but as PV cells are designed specifically to absorb sunlight, let's assume they do this pretty well. While some (let's say 20%) of a ray of sunlight is reflected back into the chamber, it would surely be caught by the next PV cell and absorbed wholly (unless, possibly, that PV cell is already working at maximum absorption, which, if is the case, negates the point of bothering to reflect in the first place.)

      -9mm-

    7. Re:Even better by Anonymous Coward · · Score: 5, Funny

      Like your 'n' got absorbed?

    8. Re:Even better by Anonymous Coward · · Score: 0

      because if you don't you'll end up being like Hunter S.

    9. Re:Even better by yincrash · · Score: 0

      Next thing you'll be telling me is that we can make new fangled lasers out of them too!

    10. Re:Even better by Anonymous Coward · · Score: 0

      as from "dinn't" ?

    11. Re:Even better by mike5904 · · Score: 1

      Well, the photoelectric effect is the process in which the energy of a photon causes an electron to jump off of its parent atom. Do this a bunch of times and you have a current. Once a photon is "converted" in this sense, it no longer exists as a photon, and as such you can't complete the procedure a second time. Perhaps such a process might be able to increase the efficiency by capturing the light that was not utilized by the solar cell (since techincally any light that gets reflected off of them is a loss of efficiency), but there's absolutely no way you're going to get more energy out of the system (probably less, since more surfaces mean more loss), than if you just replaced all of the mirrors with photoelectric panels. If this were not the case, it would violate the first law of thermodynamics.

    12. Re:Even better by Rei · · Score: 1

      Because evil gnomes will sneak in when you're not looking and hold their hands between the mirrors to block the light and foil your plans, obviously.

      --
      Clean coal harnesses the awesome power of the word 'clean'.
    13. Re:Even better by WiFiBro · · Score: 1

      Because you can't absorb it all at once. Check how eyes try to catch as many of the fotons flying around as they can. For the same reason chlorophyl in plants has an 'antenna complex'.

      Bad luck you cannot patent this idea as it is already in use, see for instance this paragrpah on reflection , describing such an efficiency increasing trick.

    14. Re:Even better by Anonymous Coward · · Score: 0

      Just to nit-pick.. you can only extract _exactly_ the energy of the photon from a given photon. Photons can only be absorbed in full or not at all, really.

      Of course, you can absorb a photon and then re-emit a photon with less energy. Depending on how you look at it, that could be the same photon. You can think of it as the inelastic scattering of a ball off another one, transferring a bit of its energy.

      However, the difference here is that with a photon, the only properties it has is its energy/momentum, its phase, and its polarization. All these properties are changed in such a process.. so personally I don't think it's meaningful to speak of the emitted photon being the 'same' photon as the incident one.

    15. Re:Even better by databyss · · Score: 1

      very true, but the nanotube structure takes care of absorbing the reflected photons... putting in mirrors will just provide a useless surface that won't be able to absorb energy.

      --
      Hmmm witty sig or funny sig? Maybe elitest techy sig!
    16. Re:Even better by maaleron · · Score: 1

      Technically, I believe it's the 'd' that got absorbed.

      As a side note... god bless KDE and aspell... spell checking in a Slashdot entry box. Fantastic

    17. Re:Even better by uhlume · · Score: 1

      Technically, I don't believe that's the misspelling the GP was referring to...

      --
      SIERRA TANGO FOXTROT UNIFORM
    18. Re:Even better by necrodeep · · Score: 1

      Oh my lord... they found a better way to blot out the sun!

    19. Re:Even better by AmericanInKiev · · Score: 1

      Mirrors have a cost, to use a mirror to reflect the nominal light reflected off of a solar cell back into the solar cell would never be as cost effective as using the same mirror to reflect the much higher energy of direct sunlight onto the cell.

      At some point the additional cost of higher effeciency isn't the best use of materials.

      30% effeciency is a workable number - and the cost of energy isn't affected as much by doubling this number as it is by other concerns, such as tracking the sun, storing the energy, and injecting into the grid.

      The better reuse of PV energy is to cool the solar cell with water and bathe yourself in the outflow.

      AIK

    20. Re:Even better by mike5904 · · Score: 1

      Well, in my own defense, I was just referring to a hypothetical situation. I never implied that it would actually be a good idea to use either mirrors or other solar panels to capture light reflected off of the cells. I have no idea how much light is actually reflected, but unless you're pressed for space, obviously it would be better to use your materials to capture "fresh" sunlight.

    21. Re:Even better by cartmancakes · · Score: 1

      So, if the absorbtion rate could ever be 100%, then we wouldn't be able to see the solar cells, right? Cool idea for a REAL invisibility cloak!

    22. Re:Even better by Zoyd · · Score: 1

      So, if the absorbtion rate could ever be 100%, then we wouldn't be able to see the solar cells, right?

      No. They would be black.

      Cool idea for a REAL invisibility cloak!

      Invisiblility implies shearness (see-through-ness). You can't see through perfectly black things that, by definition, absorb all light that hits them.

    23. Re:Even better by AmericanInKiev · · Score: 1

      They are pretty dark - Solar Cells are. Even though their effeciency is small 10%-30% The energy which is not converted to electricity is probably converted to heat - and ironically, solar cells become more effecient with more light - but less effecient when the get hot.

      They must require a substantial energy difference to operate.

      The best solution currently, it to cool the cells with water and use the hot water to take a shower.

      AIK

  2. Small problem by winstonmeister · · Score: 5, Funny
    "Reflections off the Gothamesque towers would provide more opportunity for each photon of sunlight to interact with the p/n junction of the cell.
    Unfortunately, Batman tends to work at night, so solar cells won't be of too much help.
    1. Re:Small problem by game+kid · · Score: 1
      Unfortunately, Batman tends to work at night, so solar cells won't be of too much help.

      Have you ever seen the Batsignal? Uses a lot of much needed power. If Gotham doesn't use solar power for that they'll soon need Captain Planet's help instead.

      --
      You can hold down the "B" button for continuous firing.
    2. Re:Small problem by drinkypoo · · Score: 1

      Maybe they could convert the batmobile to hydrogen, and use the solar for disassociation of water. Personally, I'd like to see this made into a portable nitrous oxide manufacturing machine. It could at least provide the power, and everything you need is present in air if you can figure out a way to separate out nitrogen, too. :)

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    3. Re:Small problem by tinkerton · · Score: 1

      I've got this solar powered flashlight lying about somewhere. Never found good use for it, but maybe Batman is interested.

    4. Re:Small problem by Anonymous Coward · · Score: 0

      and then they invented batteries...

  3. Obvious geekthink by Anonymous Coward · · Score: 1, Informative

    Even though this has only been used to generate towers that are microscopic in size, let the "and I bet this can be applied to beanstalks!" threads start in 3...2..1....

  4. But what could you do... by Fitzghon · · Score: 5, Funny

    ... with a Beowulf cluster of these things?

    Fitzghon

    1. Re:But what could you do... by __aawavt7683 · · Score: 1

      Imagine a farm of these! You could power a Beowulf cluster!

      -DrkShadow

  5. Carbon Nanotubes....in towers? by eddiegee · · Score: 4, Interesting

    So where's my Space Elevator?

    1. Re:Carbon Nanotubes....in towers? by jdray · · Score: 1

      I was wondering whether or not you could use this technology to grow cables for a space elevator. If you could get a spiral form going, it might be able to spew out cable (okay, it would probably be too slow to be called "spew") pre-formed.

      --
      The Spoon
      Updated 6/28/2011
    2. Re:Carbon Nanotubes....in towers? by wahsapa · · Score: 0

      its on top of the tower(construction finish date 2103)

    3. Re:Carbon Nanotubes....in towers? by Rei · · Score: 4, Interesting

      No. The problem with tubes this small is that there is insufficient van der waals force holding them together; the tubes are strong, but the force keeping them as a single bundle isn't. And probably won't be unless we can produce quite large tubes. One alternative is that, under high pressures, nanotubes interlink and trade their strong sp2 bonds (graphite) for weaker, but still quite strong sp3 bonds (diamond) between tubes. In theory, these interlinked ropes (not really nanotubes, but a new material) should be quite producable once regular vdw-bonded nanotube ropes without any sort of binder in them become producable and affordable.

      There's another problem with space elevators, though: not only would interlinked tubes prove somewhat weaker than non-interlinked tubes in all likelyhood, but non-interlinked SWNTs proved rather weak in direct tensile strength tests. One test that I read about had a maximum strength of just over 60GPa, instead of the >100 typically called for to produce a reasonable space elevator on Earth. Now there are many different types of SWNTs depending on how the graphite is rolled up, so they could vary, but signs don't look good.

      --
      Clean coal harnesses the awesome power of the word 'clean'.
    4. Re:Carbon Nanotubes....in towers? by Anonymous Coward · · Score: 0

      your *solar* space elevator...

    5. Re:Carbon Nanotubes....in towers? by Vict0r · · Score: 1
      Also, the cost of production of CNTs is still rather high, a CNT space elevator many, many kilometers long is probably still to expensive for government to be interested (since they'll probably be the ones to fund it).

      However, Double Walled Nanotubes have some interesting properties that might be able to surpass the listed "short" comings of SWNT, specifically the thermal and chemical properties.

      I hope this isn't considered nested posting or something like that.

      --
      "There are many things that are known and things that are unknown; in between is exploration."
    6. Re:Carbon Nanotubes....in towers? by Rei · · Score: 1

      Unfortunately, that won't work - these will be denser. The two critical factors for keeping the distance-to-width-doubling low for a space elevator: material density and tensile strength. Lets say that these are twice as dense. If the tensile strength is the same but the density is doubled, the distance between width-doublings of the cable is halved, which means that the cable has to double in width twice as many times, which is generally a completely unacceptable situation.

      Still, they're interesting :)

      --
      Clean coal harnesses the awesome power of the word 'clean'.
    7. Re:Carbon Nanotubes....in towers? by phoenixTMW · · Score: 1

      It's not just van der Waals holding nanotubes in bundles together; it's also pi-pi stacking. And let me tell you, those bundles are pretty tough to exfoliate, at least from a chemical standpoint.

    8. Re:Carbon Nanotubes....in towers? by Rei · · Score: 1

      And let me tell you, those bundles are pretty tough to exfoliate, at least from a chemical standpoing

      Unfortunately, not from a tensile strength standpoint. The strongest nanotube rope strengths I've read about simply used nanotubes in a binder, and were about as strong as kevlar. Pure nanotube ropes tended to be under 1GPa, if I'm remembering the articles I've read correctly.

      --
      Clean coal harnesses the awesome power of the word 'clean'.
  6. Slightly OT by frankthechicken · · Score: 4, Interesting

    For soldiers operating in the field, especially in desert areas that receive lots of sunlight, the new "solar tube" cells could provide an alternate power source for the growing number of electronic devices they use

    Given the amount of energy this "growing number of electronic devices" probably puts out, doesn't it make the slodiers easier to spot due to the energy signatures they are putting out? If so, doesn't it slightly impact on the actual usefulness of the electronic devices?

    I'm guessing this is factored in, but how much shielding is possible, and how far would the new "solar tube" be able to be shield it's energy signature from the enemy?

    1. Re:Slightly OT by databyss · · Score: 1

      I doubt the enemy will be carrying tricorders with them to pick up the energy signal. They'll probably be using eyes just like the other soldiers.

      --
      Hmmm witty sig or funny sig? Maybe elitest techy sig!
    2. Re:Slightly OT by Locke2005 · · Score: 1

      You mean, unlike the energy signal of the fricken humvee they're riding in? I suspect the soldiers doing covert ops on foot don't carry as many gadgets, and probably keep what they do carry turned off most of the time. Anybody else is putting out a huge infrared, sound, and electromagnetic signature from their vehicle anyway...

      --
      I've abandoned my search for truth; now I'm just looking for some useful delusions.
    3. Re:Slightly OT by Bradac_55 · · Score: 1

      That depends, how do you 'spot' the energy signature of a Magellan Meridian Platinum Mapping handheld? (A very nice GPS unit that has seen action in Iraq). The other big item would be personal cell phones. Anything else is probably supplied by the military and will be shielded (sat phones, laser finders, etc) so it's not that big of a deal.

      I was the idjut during desert storm that had to repair most types of the electronics and crypto units used in the field and never ran into a problem with anyone 'spotting' any soldier using military spec equipment. Granted soldiers are caring more non-spec personal items but it's not like you can get a thermal or low light image of a cell phone in use, you're going to pick up the solider first.

      - Brad

    4. Re:Slightly OT by Rei · · Score: 4, Interesting

      I'd actually been thinking about that. For example, picture the speaker on a communications device. Speakers give off a lot of EMF (they're effectively a big fluctuating electromagnet pulling on a diaphragm) - even shielded ones are generally pretty easy to detect and tell what sound was coming from the speaker. CRT monitors (not that common on portables) pump out lots of EMF, too (run "Tempest for Eliza" some time - you don't even need a sensitive directional antenna to listen in). I've read about keyboards have been tempested from over 50 feet away.

      What good is an encrypted signal when the people that you're hunting in a city have a good parabolic antenna pointed at you through a wall that they're hiding behind and are listening to the signal from your radio? Heck, they don't even need to know what you're saying, just that you're there.

      Of course, pretty much everything about warfare would be a heck of a lot harder if the US actually fought a *real* enemy instead of collapsing third-world nations armed with reject Soviet equipment from the 1950s and 1960s.

      --
      Clean coal harnesses the awesome power of the word 'clean'.
    5. Re:Slightly OT by qkslvrwolf · · Score: 1

      What good is an encrypted signal when the people that you're hunting in a city have a good parabolic antenna pointed at you through a wall that they're hiding behind and are listening to the signal from your radio? Heck, they don't even need to know what you're saying, just that you're there. Answer: you don't get that close. Even in the "close in" fighting of a city, chances of being 50 feet from someone is really, really slim. Unless they're moving very fast, in which case you'd have other problems. As for everything about warfare being harder if we fought a "real" enemy....no it wouldn't. All a real enemy does is provide us with more targets. Trust me. The USAF talks about "targets per sortie", which means, even (especially) against a real opponent, a single us aircraft can expect to get multiple kills every time out. I heard a speech from a british group captain recently saying that the US needs to help the brits keep us if we want them to keep fighting with us...and they're about as technologically advanced as anyone else on the planet. No, sad to say, the best way to fight the us is to do exactly what they're doing to us in Iraq...which is why we ought to get the hell out of there.

      --
      Or have you only comfort...that stealthy thing that enters the house and guest then becomes host, then master - KG
    6. Re:Slightly OT by Linker3000 · · Score: 1

      For soldiers operating in the field, especially in desert areas that receive lots of sunlight, the new "solar tube" cells could provide an alternate power source for the growing number of electronic devices they use

      Woah, let's back it up a bit here - if we have a more efficient form of generating electricity, we will reduce the cost of producing hydrogen which will make it cheaper and more viable to move to a hydrogen economy so we won't need all these soldiers in desert countries protecting the oil^h^h^hfreedom of the formerly-opressed citizens anyway?!

      --
      AT&ROFLMAO
    7. Re:Slightly OT by NoizeyMike · · Score: 1

      I have be told numerous times, and I won't stand by it (nor do I know where the source is) that in the first Gulf War no more than 10% of the percision guided missiles ever hit their target. I'm assuming that smart bombs haven't improved that much since that point. Perhaps that means a single us aircraft can expect to get multiple kills every time out, but they aren't legit (under the Geneva convention ;) ). Err. I'z iz takin us farther in to OT territory.. :) couldn't resist, Mike

    8. Re:Slightly OT by Quantum+Fizz · · Score: 1
      You mention two things - spying via EMF and sound.

      Trying to pick up a speaker's EMF will be quite difficult because a 1kHz electromagnetic oscillation will have a wavelength of about 300 km! Try making a stealth quarter-wave antenna with that frequency. Of course you can inefficiently pick up signals with non-matched antennas, but I don't know how efficiently you can do this for such a huge wavelength mismatch.

      You mention CRT scanners (I remember reading about such raster scanners awhile back), but these are more feasible because a 1024x768 screen refreshed at 75Hz will put out a baseline of roughly 60 MHz (a wide-bandwidth signal with notable harmonics and subharmonics, depending on the screen image). Making a small 60MHz antenna is quite doable (quarter-wave antenna would be about 1 meter). So you cannot really compare CRT scanner to a speaker-EMF scanner.

      On the other hand, using a parabolic dish with a microphone to pick up the actual acoustic transmissions of a speaker is certainly more feasible. However at large distances it will be hard to pick out one speaker out of many noise sources in a room, unless you use bigger and bigger dish (this is due to diffraction). So you'd need to be fairly close for this method to work. Soundproofing would also be a damper (literally), and you can bet any sensitive room would (ideally) be soundproofed. Anyway this method might work if you were in an apartment across the street from your target in an urban landscape, where you could be fairly discrete. B this would be far more difficult in the field, unless you luck out and find some unguarded forest nearby your target for example.

      You can always shoot a laser on a window and pick up the oscillations that cause the beam to move, but that's also tricky to do in the field without being spotted. Maybe this would be more feasible at larger distances, though.

    9. Re:Slightly OT by maaleron · · Score: 1

      Someone needs to explain to me how Iraq was a collapsing third world nation before the US invaded. Sure they were controlled by a slightly sadistic dictator, but sitting on the bed of oil that they do, they could hardly be considered third world.

      I won't even get in the point where, in all honesty, how else do expect you expect these nations to fight the 'world's greatest military machine'.

    10. Re:Slightly OT by amliebsch · · Score: 1

      I'm guessing it's factored in, but honestly, soldiers put out kilocalories of EM in the infrared range already; it's called BODY HEAT. The few additional watts from electronic devices are probably not going to make that big of a difference, unless you're a pathfinder or something...

      --
      If you don't know where you are going, you will wind up somewhere else.
    11. Re:Slightly OT by Slinky+Puppet · · Score: 1

      The poverty of Iraq was, in large part, due to many years of war with several neigbours (such as 10 years of war with Iran). This was followed by years of UN sanctions that prevented the importation of anything useful to the military. Of course, lots of things are useful to the military. In addition, Iraq could not easily export their oil, except under certain conditions (oil for food programme, for example).

    12. Re:Slightly OT by Berner · · Score: 1

      Using a cranial-implant speaker and a microphone implanted in the jawbone would remove or at least reduce the chance of being detected due to "EMF". It would also reduce the energy requirements. To solve the CRT leakage I would use microwattage lasers shoting directly into the eye, I serioulsy doubt that a sensor can pick up a microwatt at any significant distance. These techs may sound somewhat Heinlein'esqe but I suspect that it could be developed quite quikly if it where deemed nescesary. If the world was to see the kind of compressed military development that it saw during the second world war using todays tech, I wouldn't be surprised if these techs and alot of others would emerge as useful commercial technology after hostilities ended. PS. Pardon my spelling. DS.

    13. Re:Slightly OT by Anonymous Coward · · Score: 0

      calories are a unit of energy, not power.

  7. Terribly sorry, but by geeber · · Score: 0

    You might say they were grown in ivory towers, even.

    Ar ar, sorry couldn't resist.

    1. Re:Terribly sorry, but by plsander · · Score: 1

      No, this is Georgia Tech - they don't have Ivory Towers for research at Tech. They have Red Brick Towers. (And brick fountains, brick sidewalks, brick crosswalks, brick clyde crossings...)

      This bit of nostalgia brought to you thanks to Clyde Robbins.

      -Peter, who graduated from Ma Tech in 1988.

  8. But not word... by davecrusoe · · Score: 5, Interesting

    "For soldiers operating in the field, especially in desert areas that receive lots of sunlight, the new "solar tube" cells could provide an alternate power source for the growing number of electronic devices they use. Without the need for trucking in fuel, compact PV cells could directly power certain applications or be used to recharge batteries in soldiers' equipment..." But, no word about innovative residential or consumer uses for the material? What about powering mobile computing systems for rural schools in India, or for use in purifying water in Africa? Sigh.

    1. Re:But not word... by Soulflame_2 · · Score: 1

      Military applications drive innovation. The consumer applications of the technology are coming.

    2. Re:But not word... by databyss · · Score: 1

      You should start up a company that does just that!

      Imagine the great things you could bring about in the world!

      Or did you mean that somebody else should do it?

      --
      Hmmm witty sig or funny sig? Maybe elitest techy sig!
    3. Re:But not word... by Anonymous Coward · · Score: 0

      What do you really expect? DARPA gives out lots of grants to people researching science and technology. The WHO, not so much. So regardless of whether you actually intend for a humanitarian use of your discovery, you couch it in military uses, to get the grants for continuing your research.

    4. Re:But not word... by Stile+65 · · Score: 1

      The three-dimensional cells could also be useful in space applications, where power is in constant demand and launch weight is critical. Ultimately, they also could be used in developing nations where low-cost electrical power is vital to expanding economies.

      Missed this paragraph, did you?

      --
      I claim first use of "Error No. 0B" - or "No. 0B error." It'll be the new ID 10T!
    5. Re:But not word... by Doc+Ruby · · Score: 1

      That's because the military contractors have control of hundreds of billions in unaccountable budgets. So we have to wait while their braindrain sucks up the innovators, then maybe kills a lot of people so they can't keep it secret anymore, then we can get started on consumer apps. That's pretty wasteful.

      --

      --
      make install -not war

    6. Re:But not word... by That's+Unpossible! · · Score: 1

      What about powering mobile computing systems for rural schools in India, or for use in purifying water in Africa?

      Until India and Africa come up with the money to drive this technology, they'll have to wait for those that are actually paying for it to develop it.

      Sigh.

      --
      Ironically, the word ironically is often used incorrectly.
    7. Re:But not word... by Adeax · · Score: 2, Insightful

      Powering mobile computing systems for rural schools in India isn't mentioned because the rural school system of India isn't paying for the research - the DoD is.

    8. Re:But not word... by gmcraff · · Score: 2, Insightful
      Remember that a lot of technologies start in military applications long before they move out to civilian use.

      Why is this?

      Firstly, because military problems attract money. Privates bitch to Sergeants, Sergeants bitch to Captains, Captains bitch to Colonels, Colonels bitch to Generals, Generals bitch to Congress, who has the people's money. If a private is too hot, too cold, too vulnerable, lacking ammo, too slow, too visible, etc, it becomes a problem that the Generals will address in order that the solution will be a military advantage.

      Secondly, because the military will accept a sub-optimal solution if it addresses the primary problem really well, or if it addresses a previously unaddressed problem. Consider the WWII company radio. It was expensive, heavy, bulky, the range wasn't very good, the transmission quality was horrible and it was fairly fragile. There was probably a very high failure rate in the manyfacturing process. It required a dedicated soldier to bear and operate it, to the exclusion of food and ammo, which reduced his combat effectiveness and survivability. It was recognizable from a distance, which made him target number one for snipers.

      All that being true, a company with a radio was part of an army. A company without a radio was a isolated group of men without support or supply that would surely only last a single firefight, if that. As technology developed, the radio got lighter, cheaper, more reliable, and encrypted. Soon it was affordable to equip a platoon with a radio, then individual squads. At a certain point along this progression, the technology really took off to the civilian market once it was cheap, reliable and small enough for, say, an important business person to have a brick-size device. With the new influx of money from a consumer market, the radios became smaller and cheaper until just about every one of us has a personal radio: the cell phone.

      So, while you beat your breast and cry out to the cosmos, "Why does all the technology has to have military purposes first," remember that the military purposes will wring bugs out of the technology, establish an industrial base from which to launch into the civilian market, and provides a "reference" that business can rely on. If you try to jump straight into the civilian market with a buggy technology, no problems-solved stories and no industrial base, you'll be out of business like a dot-COM unless you have VERY deep pockets, or very stupid/very far-sighted (HA!) venture capitalists.

    9. Re:But not word... by Shotgun · · Score: 1

      Firstly, because military problems attract money. Privates bitch to Sergeants, ...

      Uhm, not quite. The real mechanism is...

      Privates DIE, newspapers and parents of dead privates bitch to Congress, who has the people's money.

      Same end result, of course.

      --
      Aah, change is good. -- Rafiki
      Yeah, but it ain't easy. -- Simba
  9. cat-eyes by Anonymous Coward · · Score: 0

    Turn your cat (owl, tiger,...) into something useful and remove it's tapetum lucidum out of it's eyes into your solar cell, not quite the effect you intend but a lot more feasible if you ask me.

    1. Re:cat-eyes by Anonymous Coward · · Score: 0

      "its".

  10. Re:Slightly OT and not thought out by clonan · · Score: 1

    While it COULD be possible to detect solidlers using similar technology, it would still be VERY difficult.

    #1 as you stated most of the electronics are probably well shielded so as no to put out much radiation.

    #2 a single soldier or even a squad is a very small target from any distance and if you are close enough to really zero in then you just use your eyes.

    #3 By it's very nature a photovoltaic cell will NOT put out radiation. It is built to absorb radiation, not put it out! Radio waves are produced by moving electrons back and forth quickly. A photo power cell only move electrons in one way and at a relativly low power. The photo cell will probably need NO shielding...and even if it did, most cells use visible light for power so you could shield radio waves to your hearts content and not affect the function f the device.

  11. Re:But no word... by davecrusoe · · Score: 1, Insightful

    But that's only because we emphasize military spending, and military might. Personally, I'm of the belief that education and educational applications - such as invention, or innovative teaching and learning - in addition to practical humanitarian applications should drive technological innovation.

    If we maintain the mindset that military applications drive innovation, then that's all we'll receive. On the other hand, if we start applying for grants, and applying our funding in new directions, it's forseeable that the locus of innocation could change. I, for one, strive for such.

  12. What could we do? by game+kid · · Score: 1

    Maybe we can power a Beowulf cluster of toaster--er, computers. Or microw--I mean, cars--dammit, GTRI, you and your confusing waffle-looking wafers! But I love'em; we should make a worldwide solar-collecting mesh covering Earth with these wafers, so anyone who needs "clean" energy can have it--using, of course, some sort of redundancy to prevent something like the 2003 Northeast Blackout. How would that go?

    --
    You can hold down the "B" button for continuous firing.
  13. 20 um vertical structures?!? by Sebastopol · · Score: 3, Interesting


    preface: my nanotech is limited to semiconductor process only.

    looking at the image, the towers appear to be 20um cubes, and the tubes look incredibly uniform. That is some impressive feat to build such a tall structure!

    this makes me think of 3D model creation tools that use a laser and a tank of epoxy-like goop to 'draw' a 3D prototype of a design.

    can this accomplishment be extended to this technique to "render" nanodevices (er, microdevice machines), out of tubes?

    --
    https://www.accountkiller.com/removal-requested
  14. Why are solar cells shiny? by Doc+Ruby · · Score: 0, Troll

    They should be black. And cold.

    --

    --
    make install -not war

    1. Re:Why are solar cells shiny? by drinkypoo · · Score: 1

      How hot do solar cells get? Would it be worth it to be a combined PV/water heating solar setup? I wonder if you could get useful efficiency out of the panel if it were under an inch of water and a sheet of greenhouse plastic. Barring that, I guess you could attach it to a water block, but that sounds more expensive.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    2. Re:Why are solar cells shiny? by ScrewMaster · · Score: 1

      Nah ... the algae growing in the tank would cut down solar efficiency too much.

      --
      The higher the technology, the sharper that two-edged sword.
    3. Re:Why are solar cells shiny? by Doc+Ruby · · Score: 2, Insightful

      No, all the heat energy in the PV should be going into accelerating electrons to the cathode instead. Any heat is waste, inefficiency, and powering a cooler just consumes more energy from the net. Besides, silicon solar cells get more efficient per incident watt as they heat up - a catch-22 that should be broken by making cells with a different nanoarchitecture which captures more of the incident power.

      --

      --
      make install -not war

    4. Re:Why are solar cells shiny? by k98sven · · Score: 2, Informative

      Oh yeah. Solar cell should work in the infrared! Why hasn't anyone ever thought of that?

      Oh wait.. they have. And it simply can't be done with the solid-state solar cell technology of today. You can't have a bandgap that small and get a current.

      And yes, of course there is a lot of research going on in this.

      So, what is the point of your comment? Do you mean to say that you have a solution noone knows about, or are you bitching about the state of solar cells today because you think you know something noone else does?

    5. Re:Why are solar cells shiny? by Xybot · · Score: 1

      I think he may have been pointing out that a black tube full of water is in effect a solar cell that works in the infrared.

      --
      God was my co-pilot, but then we crashed and I was forced to eat him.
    6. Re:Why are solar cells shiny? by cr0sh · · Score: 1

      Actually, you sometimes do see solar cells mounted on heatsinks, so your idea isn't as outlandish as some would think. Generally, these cells are mounted this way only when used with an active sun tracking system and a lens concentrator in front of them (generally a fresnel) to collect more light and focus it on the cell. Since you are concentrating the light, heat becomes a real problem (think burning ants), so it needs to be dumped somehow, and this is typically accomplished via alluminum heatsinks. They tend to be passively cooled (that is, no fans or anything), but if there was enough heat to collect, might as well harness the extra energy, right?

      --
      Reason is the Path to God - Anon
    7. Re:Why are solar cells shiny? by Doc+Ruby · · Score: 1

      Solar cells are shiny and hot. They'll be more efficient when they're black and cold. What's so wrong about mentioning that in a discussion of breakthrus in solar cell material science? In fact, what's wrong with you just answering "current tech doesn't allow bandgaps in infrared, so they waste heat"? Do you have a shiny, hot solar cell stuck up your ass or something? BTW, smartass, they're not shiny because of anything infrared, unless your species has bugeyes in addition to rectally consuming silicon.

      --

      --
      make install -not war

    8. Re:Why are solar cells shiny? by Doc+Ruby · · Score: 1

      Moderation -1
      40% Troll
      30% Insightful
      30% Overrated

      Why did a simple inquiry into the obvious defects of solar cells, with specific desired improvements, generate so much opposition?

      --

      --
      make install -not war

    9. Re:Why are solar cells shiny? by k98sven · · Score: 1

      Solar cells are shiny and hot. They'll be more efficient when they're black and cold.

      Not today's solar cells. What's the point in increasing IR absorption when the thermal energy isn't going to go towards increasing current?

      What's so wrong about mentioning that in a discussion of breakthrus in solar cell material science?

      Because your comment doesn't add anything at all to the discussion. It has no facts in it, nor is it a question, as for instance "Why aren't solar cells black and cold?".

      In fact, what's wrong with you just answering "current tech doesn't allow bandgaps in infrared, so they waste heat"?

      Because current tech does allow bandgaps in that range. You just can't get a current out of it, unless the thing is cooled to 1 Kelvin or so.

      And what's wrong with you actually going through the trouble of Googling for an answer to why solar cells are black before announcing that they should be?

    10. Re:Why are solar cells shiny? by Anonymous Coward · · Score: 0

      Do a search on solar wall. A company sells panels that are primarily used to heat air but also have PV cells so you can get heat and electricity.

  15. a lot of solar news lately by grqb · · Score: 5, Informative
    So far this week we've had quite a bit of solar news...solar power airplane to fly around the world, another breakthrough in solar power that brings the price of solar from $8/watt to about $1/watt and now this...hmmm I should get into this business it seems!


    Carbon nanotubes are also all over the map these days so why not nanotubes and solar? I guess we'll have to wait a while until this becomes commercial though because I don't think carbon nanotubes can be scaled up very easily.

    1. Re:a lot of solar news lately by GeffDE · · Score: 1

      You know, you'd figure that the entire field of solar power got one of those special deals with /. like the one Apple has...

      --
      It has been a nervous year, with people beginning to feel like Christian Scientists with appendicitis.
  16. and by solar power... by game+kid · · Score: 1

    I mean storing solar energy from the day into a battery for the nighttime signal. Hopefully you could have guessed that, and not that a night light would be powered by a sun that's not "shining."

    --
    You can hold down the "B" button for continuous firing.
  17. You cannot let idealism trump reality by Anonymous Coward · · Score: 0

    This is like saying "I believe in a world without crime, therefore I feel free to walk through South Central LA wearing expensive jewelry."

    This is not about a mindset; its about money. Money talks, and like it or not, the military has money and will probably be able to shell out far more money to fund this technology than a rural school in India will.

    Do I like that aspect of reality? Frankly no I don't. But putting on blinders to reality does not do anyone any good.

  18. Re:But no word... by Anonymous Coward · · Score: 0

    I believe love and puppy kisses can replace the oil economy.

    You are a moron. You know nothing of consequence. Good news it's not too late.

    The reason military drives innovation is because they are the body most concerned with controlling the most extreme risk.

  19. A round of applause! by spun · · Score: 0

    Burns: Compadres, it is imperative that we crush the freedom fighters before the start of the rainy season. And remember, a shiny new donkey for whoever brings me the head of Colonel Montoya.
    [Smithers whispers to him]
    Hmm? What? Oh, and by that I mean, of course, it's time for the "Worker of the Week Award". I can't believe we've overlooked this week's winner for so very, very long. We simply could not function without his tireless efforts. So, a round of applause for...this inanimate carbon rod!

    --
    - None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
  20. Re:But not word...(seek the money) by Avishalom · · Score: 1

    it is probably a US army grant
    and they need some more money right about now

  21. Make solar cells like leaves not like guts ! by mishmash · · Score: 4, Interesting

    No. If surface area mattered then leaves (nature's way of capturing solar energy) would have folds and protrusions like the gut does to increase surface area. What leaves do is make sure that some of the light gets through to the next layer. This happens both in an individual leaf - light is not caught just at the top surface but all the way through the leaf. Also a leaves don't trap all the available light, some is left for leaves below - it's totally dark walking through a forest. Make the solar cells more transparant - thats the way to get the effect of increased surface area the article referes to.

    1. Re:Make solar cells like leaves not like guts ! by spectre_240sx · · Score: 1

      Hmm, now that you mention it, I wonder why solar cells aren't arranged in this fashion? Maybe they are sometimes, but I've never seen it before.

    2. Re:Make solar cells like leaves not like guts ! by ColaMan · · Score: 1

      Such as something like this?

      Bi-facial solar cells

      --

      You are in a twisty maze of processor lines, all alike.
      There is a lot of hype here.
    3. Re:Make solar cells like leaves not like guts ! by Albinoman · · Score: 1

      No actually, not at all. What he was talking about was to make a thin fairly transparent one, and then layer them. Similar to the many layers of semitransparent, light absorbing cells in a leaf. Cant get it any more descriptive. Yours is just panels on both sides to catch the direct sunlight, and its reflection behind it, like pointing a panel at a mirror pointed at the sun.

    4. Re:Make solar cells like leaves not like guts ! by The+Fun+Guy · · Score: 1

      Actually, the cells within a leaf are arranged in densely packed columns on the dorsal (top) side (the palisade parenchyma), with the long axis parallel to the incident angle of the sunlight, serving to allow for reflective capture much as the article describes with the nanotubes. Leaves have more open, dispersed cells on the ventral (bottom) side (the spongy mesophyll) to allow for gas exchange.

      --
      The man who does not read good books has no advantage over the man who cannot read them. - Mark Twain
  22. Re:But no word... by servognome · · Score: 1

    If we maintain the mindset that military applications drive innovation, then that's all we'll receive.
    The military is just the ultimate "early adopter" of technology. The underlying research and science is driven by educational institutions.
    One of the reasons the military is such a driving force in innovation is because, like the space program, they are constantly trying to solve problems at the "extremes". Questions like "what if half the country was nuked" was one of the main reasons for the decentralized structure of the internet.
    The hardest part of innovation is asking the right questions. "Necessity is the mother of invention"

    --
    D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
  23. Controlled growth of Carbon nanotubes by karvind · · Score: 2
    Can someone tell details about how they do it ? The sighted news articles doesn't give any details. Can they grow individual carbon nanotubes vertically ? There had been earlier work on controlled alignment of carbon nanofibers from ORNL folks. Their technique could grow the nanotubes in different directions using electric field. There is also an option of controlling the direction of growth using polarized light.

    If precise formation as well as placement can be achieved, it will get over the biggest hurdle in getting into the electronics. There are still other issues (eg. contacts, surface adsorbtion etc) to be addressed though.

    1. Re:Controlled growth of Carbon nanotubes by phoenixTMW · · Score: 2, Informative

      No one has been able to grow vertical carbon nanotubes individually without support. Problem is, when the tubes get too long, they flop over. In these columns, the tubes help support each other.

  24. double insulated towers by Anonymous Coward · · Score: 1, Interesting

    A simple and donated to the non-patentable public domain by me solution is:

    a. get double paned glass windows
    b. install on 100 story office tower
    c. channel the air from inside of one window to the one above it (chaining them until top of building)
    d. put wind turbines at top of building

    1. Re:double insulated towers by spectre_240sx · · Score: 1

      I'm sorry, I hold the patent on donating solutions to the non-patentable public domain. Don't worry about litigation, however. I'll just take your idea instead.

    2. Re:double insulated towers by platos_beard · · Score: 1

      Sorry, the basic idea's already patented and these guys say they have an exclusive license.

      --
      What's a sig?
  25. Yeah. by Grendel+Drago · · Score: 2, Interesting

    And I'm sure we'll have solar as a major component of distributed power generation right after that commercial fusion plant gets built.

    --grendel drago

    --
    Laws do not persuade just because they threaten. --Seneca
    1. Re:Yeah. by AmericanInKiev · · Score: 1

      One irony,

      Effecient solar energy is dangerous.

      Any solar collector in the hands of a moron could evaporate a target. You think ants have it bad - wait until your average home solar dish blows a gear and the focal point drifts into something else.

      BAM

      AIK

    2. Re:Yeah. by njh · · Score: 1

      A parabolic dish has only one focal point, in the obvious spot. Furthermore, an off axis parabolic reflector cannot focus properly, so they only work when they are pointed in the right direction.

      The ?irony? is that people who post anti-solar posts invariably demonstrate that they have no clue.

    3. Re:Yeah. by AmericanInKiev · · Score: 1

      First - I'm not anti-Solar.

      Solar energy is really the only renewable that has a positive correlation with Supply/Demand.

      Wind and Waves all drop out during peak months.

      I'm concerned about the saftey of concentrators in residential settings - I do understand the astimatism of a scewed reflector - how can we be sure that even with astigmatism, the focus will be rendered harmless?

      Is there a size limit?

      Fires occassionally start because of refractive materials - such as bottles in the wrong position - How can we be safe and have 500 degree solar ovens on our roof?

      AIK

    4. Re:Yeah. by njh · · Score: 1

      Ok, I was grumpy when I wrote that from the sheer idiocy I see on slashdot (makes me wonder why I even read it :). Sorry.

      I'm not sure what the model is for your steerable solar dish, are you thinking of having one per household? This seems unlikely as dishes only become reasonable around the 20m diameter mark, which would be too large for any but the largest houses. On the other hand, panels are economic even for 1cm squares for powering calculators. So I very much doubt that people will have their own solar ovens. Solar hot water is already efficiently handled with panel type heaters, which work even without direct sunlight (unlike dishes).

      So, that leaves large collectors for solar-thermal systems like the ANU combined heat and power system. You are concerned about the failure mode where the dish points in the wrong direction. In this case the dish will no longer focus to a single point, but rather to a circle along the axis of the incident rays. Hopefully this area is already cleared, as otherwise the sun will not get to the dish. It is possible that a branch is overhanging the dish, but in that cose there is a chance that it will get in the focus even with a working drive, so the real cause is poorly maintained equipment. In that case I imagine the likelyhood of causing a fire is about the same as that of a diesel generator causing a fire from its exhaust.

      So I agree that there is a potential problem, but I very much doubt it is as significant as fires caused by broken glass or cigarette butts. Most likely it will never be an issue as large dishes will be maintained professionally, and smaller installations will use panel type systems, which do not concentrate the light significantly.

  26. 20um towers? OLD NEWS! by Anonymous Coward · · Score: 1, Interesting

    This is really silly. The only thing new about this is the application idea. People have been growing multiwall nanotube towers since 1998... All the new nanotube field emission displays are based on them. Single-walled towers (which this MAY be refering to, but the article is too sparse to be sure) have been around for at least 2 years, vertical SWNT published first by Maruyama in japan, followed by a much better paper (all sorts of shapes of nanotube towers, up to 2.5mm tall... yes, MILIMETERS) by Iijima -- father of nanotubes in Science, last summer).

    - nanotube researcher

  27. Re:But no word... by w9ofa · · Score: 1

    You are a troll, AC, but your post made me laugh out loud.

    "Let a thousand flowers bloom" as my philosophy professor used to say in those matters..

    You know, the reason that the military are the ones who adopt this technology and move it forward is not just because they are well funded (they are), but it is also because the military is an organization that is accountable to itself and its leadership.

    If more humanist organizations had such strong and transparent chains of command, they might do well as early adopters of technology as well.

  28. Re:But no word... by w9ofa · · Score: 1
    Personally, I'm of the belief that education and educational applications - such as invention, or innovative teaching and learning - in addition to practical humanitarian applications should drive technological innovation.


    Um, is this technology not being research by Georgia Tech? Granted, they are seeking military funding, but does that make their invention somehow more evil?

    If they military wanted to fund research into the production of highly nutritious high-caloric food for cheap, would you be against it because the military paid for it?

    Yes, the military might use invention X for Seemingly Evil Use Y. Are you asserting that the thieving UN/random humanitarian organization is on moral high ground? Most respectable humanitarian organizations spend their budgets on operational use - they are not in the business of funding new technology. Nor would their patrons be happy about diverting funds that way. It seems to me that it is a good idea that the government is stimulating technology development through basic research, even if it is under the auspices of military funding.
  29. Hmm.... by Squirmy+McPhee · · Score: 3, Insightful
    The nanometer-scale scale towers, which would be coated by the special p-type and n-type semiconductor (p/n) junction materials used to generate electrical current, would increase the surface area available to produce electricity.

    Generally, increasing surface area on solar cells is detrimental to producing electricity, particularly if the semiconductor material is very thin. (Yes, I am well aware that it is more than counteracted by the additional light coupled into the cell, but the writer makes it sound as though increasing surface area is a magical formula for making more power. And the increase in surface area, by itself, is still detrimental.) I would very much like to know what are the "special" semiconductor materials they plan to coat the towers with.

    I don't think this is so much a breakthrough as it is just another in a long line of textured substrates for thin-film solar cells that don't even work yet and won't be hitting the market for another 10 years.

    Because their cells will be more efficient, Ready believes they can use older and more mature p/n-type material technologies and less costly silicon wafers to hold down costs and rapidly advance the project into products that can be used in the field.

    If he is going to use silicon wafers as simple substrates then his cells had better be substantially more efficient than standard crystalline silicon solar cells -- otherwise, he is guaranteed to be priced out of the market. Silicon wafers make up half the cost of a solar module, and the module materials and assembly make up another 30-35%. Assuming he can actually deposit these nanotowers and their semiconductor coatings at a cost similar to that of converting a silicon wafer to a silicon solar cell, it doesn't give him much choice but to leverage efficiency to get a lower cost per watt.

  30. Re:But no word... by Anonymous Coward · · Score: 0

    No more crack for you or your hippie womynist professors.

    The military is accountable to the people they've sworn to defend through the politicians, whitness the end of the Vietnam war for proof.

    The organizations you idealize have billions of dollars, and just piss it away with little to show for it. The erradication of small pox perhaps their one accomplishment. But they've been unable to repeat that success with polio. In the end, all they do is marginally increase the numbers of people who can subsist in a given region, breeding only misery strife and ultimately warfare.

  31. Re:But no word... by w9ofa · · Score: 1

    Nice.

    I guess the quote from my professor is a little out of context. He only said that about morons who tried to argue against rationalism. He was quite the opposite of a hippie womynist.

    Yeah, the military does dumbass stuff. So do most people, most of the time. I'm just saying, there is a tradition of accountability there that is stronger that most other organizations.

    Note that big defense contractors are the scum of the earth, but they sub out to good guys too.

  32. MOST MISLEADING TITLE EVER!!!!!!!! by Bootle · · Score: 1
    BLAR, damn you /. damn you

    When I hear towers of nanotubes, I'm thinking of god-damn space elevators

    2 microns is not exactly sky-scraping

    1. Re:MOST MISLEADING TITLE EVER!!!!!!!! by karvind · · Score: 1
      Actually if you think about it, it is no less than a tower

      A typical carbon nanotube is ~1-5 nm in diameter. A 2 micrometer long nanotube means an aspect ratio (length/height to diameter) of almost 1000. Even the tallest skyscraper don't go beyond 7:1. WTC had height to width ratios of 6.49 to 1. Bank of American plaza has the highest with 7.24 to 1.

  33. A Story Hits Home by 06metzp · · Score: 0

    Very interesting, considering that Applied Sciences, Inc. is considering building a nanotube production facility in Lima, OH; about 20 miles from where I live. With it being a new facility could they perhaps get into this production method?

    --
    This sig left blank for page turns.
  34. I'm waiting... by suitepotato · · Score: 1

    ...for the ultimate advance in environmentalism where we finally get to be as comfortable as we're shooting for with present tech and yet as organic as you can get: living everything. They're going in the right direction but this is very early nanotech theorizing. I'll wait for the nano-engineered biomechanical living buildings which eat all waste output from the residents, absorb ambient thermal and light energy, and are self-repairing. I'll be dead before they manage it, but it's a reassuring and hopeful dream...

    --
    If my grammar and spelling are off, I am [distracted/tired/careless] (take your pick)
    1. Re:I'm waiting... by Valdrax · · Score: 1

      There are many applications for which mechanical methods are inherently superior to biological ones due to limitations of biological life. For example, despite its obvious efficiency, why do you think that no life on Earth has evovled wheels? Why are hydraulics not subject to the cube-square rule that limits muscular efficiency? How much food do you think it would take to feed a city of living skyscrapers, and how long would it take to grow them instead of build them? How would you air condition the buildings? What do you do if the buildings catch an incurable disease (say through an act of bioterrorism) and die?

      I did a lot of thinking about this when designing a SF setting a long time ago and came to the conclusion that "living everything" is a suboptimal solution unless you come from somewhere with no useable mineral and metal deposits (like a carbon and nitrogen "rich" gas giant). "Cyborg Technology" that uses living systems in the few places where they're better and mechanical systems for structure, propulsion, etc. are much, much more likely.

      --
      If it's for-profit but free, you're not the customer -- you're the product (e.g., the Slashdot Beta's "audience").
  35. Re:But no word... by teromajusa · · Score: 1

    One of the reasons the military is such a driving force in innovation is because, like the space program, they are constantly trying to solve problems at the "extremes".

    Another is that they have lots of money. I imagine if we funded the department of education the way we funded the military, we might have all sorts of research grants for building new education tools.

  36. Re:But no word... by servognome · · Score: 1

    I imagine if we funded the department of education the way we funded the military, we might have all sorts of research grants for building new education tools.
    I doubt it, while the problems for military applications are complicated, they are easy to identify. While I agree schools are under funded, what exactly innovative would you get with $40 billion more in education? Building more schools and hiring more teachers is not innovative. If you're thinking giving more money to universities to do research, that goes to the science and theory side (we'll have more thingies like carbon nanotubes we won't know what to do with), not to innovative applications.
    Let's say you do fund educational research more, the military will still be the first in line to exploit it. The military would love to have more effective training techniques, improved methods of learning languages, psychological control techniques (both positive and negative), new ways to allow troops to multi-task effectiely, identification/modification of behaviors, etc.

    --
    D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
  37. You made it dude by Bonch+Panther · · Score: 1

    I was in DDL lab today and overheard some dude at random discussing your post on the front page of /. Congrats dude, you made it to the big leages. N|=

  38. No. by uhlume · · Score: 1

    As from "photon".

    --
    SIERRA TANGO FOXTROT UNIFORM
  39. Slightly Odd by tinkerton · · Score: 1

    Why do they give such an exotic example of usage. Too expensive in other cases so a tradeoff with surface is made? Not usable on satellites?

    I didn't see the yield with the new technology?
    I thought the record was somewhere around 35%.

    I can see that less surface means better portability 'in the field'.
    So maybe the only market at this moment is when transportability outweighs all other factors.

  40. Re:But no word... by Threni · · Score: 1

    > One of the reasons the military is such a driving force in innovation is
    > because, like the space program, they are constantly trying to solve problems
    > at the "extremes"

    Another reason is the billions of dollars the US spends every year improving the ways their armed forces can kill people. It's funny - for a country so opposed to socialism and the idea of a welfare state, they certainly dish out a lot of cash to undeserving people.

  41. But how are the Bilderbergers related to this? by tilleyrw · · Score: 1

    All tin-foil hat wearing paranoics want to know!

    --
    This post encoded with ROT26. If you can read it, you've violated the DMCA. Handcuffs please, sergeant.
  42. Old News by Anonymous Coward · · Score: 0

    I would be impressed if guys in Korea didn't come up with this a little over two years ago. Heres the reference for anyone that cares: "Vertically aligned carbon nanotube growth by pulsed laser deposition and thermal chemical vapor deposition methods", J. I. Sohn, C. Nam, Seonghoon Lee, Appl. Surf. Sci. 197-198, 568-573, 30 September (2002). 1.295

  43. MOD PARENT UP - I'm outa mod points! by markdowling · · Score: 1

    First time I've done it but this is an excellent explanation of how the world does work, even if it would be nicer if it worked the way the next parent up wanted.

  44. parent is chemical gibberish by Anonymous Coward · · Score: 0

    Clearly, at least 3 mods haven't taken high school chemistry and are impressed by a smattering of units and numbers.

    So very slashdot, so very disappointing.

    1. Re:parent is chemical gibberish by Rei · · Score: 1

      Exactly what are you claiming is incorrect? Need a paper on the subject of the interlinks? How about one on the tensile strength tests? (not the same study that I saw before - they got even lower numbers, but were testing on small ropes instead of individual tubes)

      In short: What exactly are you challenging?

      --
      Clean coal harnesses the awesome power of the word 'clean'.
  45. Another example by Andy+Dodd · · Score: 1

    Look at the solid-state accelerometers and gyros used in state-of-the art automotives. (Subaru's Vehicle Dynamics Control, and the similar Volvo system they plug in their ads for the XC90, etc.)

    Take a guess what those solid-state accelerometers and gyros were originally created for...

    --
    retrorocket.o not found, launch anyway?
  46. Re:20um towers? OLD NEWS! by Sebastopol · · Score: 1


    Nanotube researcher--

    So can we fabricate things out of these tube structures, like that modeling I mentioned in the original post? Or are these more like tubes that carry liquids or individual atoms?

    Any word on what they are good for, or is it just a milestone in nanotech???

    --Someone fascinated by nanotech

    --
    https://www.accountkiller.com/removal-requested
  47. STUPID! by Anonymous Coward · · Score: 0

    If we all used efficient solar power and oil wasn't even worth drilling for, then do you think we would need all those soldiers in the dessert?

    It's nice to see they're thinking about their FUCKING WAR MACHINE when there are people starving all over this planet, but fuck 'em, right? That's what I say about 'the troops'

    What are they fucking doing over there, anyway? Trying to stop the poeple that are 'terrorists'? The poeple in IRAQ were not like that before we got there. They did not fight us when we took over. They couldn't. We had cluster bombs, they had guns. Don't you think if they had WMD they would have used them? Now, a year later, with their country still in shambles, yet still occupied, they want us out. In the Iraqi's eyes, we have done much much more damage to their country than Saddam did the entire time he was 'ruler' (I use that loosly, as RUMSFAILED was the guy that set him up in power) And to top that, Saddam did not like Fundamental Islamists! His country was a secular state. (sound familiar, amuhrrricuns) Now it's overrun with religious freaks wanting a jihad and calling up OSAMA BIN MISSIN on the phone. Of course, chaos is great for plundering and stealing, and I ain't talking about the baghdad museum ...

    Hello?

    $9billion?

    Where Are You?

    Hello?

    1. Re:STUPID! by Anonymous Coward · · Score: 0

      awww...poor baby.

  48. Solar Roof by AmericanInKiev · · Score: 1

    In order to conceive of a zero-carbon world which meets current per capita energy consumption for an dramatically increasing consumer base (think china with air-conditioners and hummers), We cannot take anything off the table - our buildings need to capture Solar energy at high rates of effeciency at competative rates.

    Assuming energy demand to be part heat, part A/C, part light, and part electricity, we should ask first how much of that could be extracted from a 40% effecient Solar roof, and second, how can we collect the energy for market cost.

    Say we use a fresnel reflection array - a spherical reflector flattened into inexpensive roof panels - then float moving "receivers" in the focal point.

    It has some issues - such as astigmatism - but assuming some variation of a flat-array concentrator were possible, and the receiver could provide A/C light and electricity - that would be great - but what about the dangers?

    Kid climbs on the roof to chase a ball - goes up in smoke.

    So the solution lies in managing the risk with multiple arrays of a safe and smaller size, by protecting the focal zones, and ensuring a fail-safe design.

    There is a lot of waste in generating solar energy far from the point of use.

    If you need heat - it makes little sense to generate heat - then steam, then electricity - then heat.

    So - I'm thinking that we need to find livable solar designs - and the risk is worth considering.

    AIK