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Power Technology

Printable, Rollable Solar Panels Could Go Anywhere 187

Posted by timothy from the why-isn't-my-car's-dome-light-an-led dept.
Al writes "A startup based in Toledo, Ohio, has developed a way to make large, flexible solar panels using a roll-to-roll manufacturing technique. Thin-film amorphous silicon solar cells are formed on thin sheets of stainless steel, and each solar module is about one meter wide and five-and-a-half meters long. Conventional silicon solar panels are bulky and rigid, but these lightweight, flexible sheets could easily be integrated into roofs and building facades."
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Printable, Rollable Solar Panels Could Go Anywhere More

Printable, Rollable Solar Panels Could Go Anywhere

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  • Imagine that (Score:5, Insightful)

    by tyrione ( 134248 ) on Sunday June 07, 2009 @05:51PM (#28244925) Homepage
    Isn't it amazing how all of these advancements show up when given a little push?

    • Re:Imagine that (Score:5, Informative)

      by jshackney ( 99735 ) on Sunday June 07, 2009 @06:07PM (#28245059) Homepage

      From this [technologyreview.com] article, "Building-integrated photovoltaics (BIPV) have been around since the late 1980s, Warner says, but only lately have they begun to see some success with large commercial and residential developments. Recent advances in flexible thin-film photovoltaic materials--such as those sold by United Solar--are allowing manufacturers to more easily integrate photovoltaics directly into the roofs and facades of buildings."

    • Re:Imagine that (Score:5, Interesting)

      by Anonymous Coward on Sunday June 07, 2009 @06:24PM (#28245175)

      "Imagine that (Score:3, Insightful)
      by tyrione (134248) on Sunday June 07, @06:51PM (#28244925) Homepage
      Isn't it amazing how all of these advancements show up when given a little push?"

      First, what "little push" would that be? You (quite deliberately) don't say. Second, quite frankly, the technique means crap, because they are inefficient, cheap panels, which makes no sense unless you have a huge roof.

      The main reason stuff like this is coming to market is because energy prices were and will be so high. The second reason is that the advent of the computer and hence technology age, more people have the means and opportunity to look into and acquire the materials without going through a misinformed, costly local middleman.

      Still, this is a pretty crappy system, a part of the whole solar setup, and /. should know better. A HUGE part of the system cost aren't the panels, it's the damn electronics, and those prices are really high for a large installation. Anyone who has looked into solar panels, whether hot water pv, knows this. For non-grid tie but grid tie quality AC power, the inverters alone are damn expensive. Those prices aren't likely coming down, given the amount of quality raw material in them which keep going up due to global demand.

      In a lot of situations, a better system is going with a geothermal heat pump or similar, not your entire roof of crappy, inefficient solar panels, tied to your high quality inverter, and thousands of dollars in batteries. I like solar a hell of a lot, but what we need is highly efficient, cheap flexible panels, with correlating consumer priced inverter and battery tech, not this crap.

      • Re:Imagine that (Score:5, Interesting)

        by wisty ( 1335733 ) on Sunday June 07, 2009 @11:13PM (#28247011)

        Inverters are a cost, but thin film is no worse off - your inverter won't care that you have a larger area of cellls to produce the same voltage.

        Besides, a lot of electronic equipment can run off DC. Why should you invert the power, then run it through a rectifier, then pump it into your laptop?

        AC power is good for long-distance transmission, but it's no better for consumer use. Air conditioners might prefer AC, but mostly a move to DC could be just as good. Houses could be wired to have an AC system (for obsolete equipment, and stuff that needs electric pumps), and a low voltage DC rail (for new stuff). It might also mean cheaper electronics, if you don't need a bloody rectifier in every piece of white plastic you own.

        Edison FTW!!!!

        • Re: (Score:2)

          by Rei ( 128717 )

          Besides, a lot of electronic equipment can run off DC. Why should you invert the power, then run it through a rectifier, then pump it into your laptop?

          To change the voltage. Historically, it's been hard to change DC voltages in a small, efficient, compact device. It's possible nowadays, however, so one can hope that things like Green Plug [greenplug.us] take off. I'd love to see something like that be standard for house wiring.

          • Re: (Score:2)

            by wisty ( 1335733 )

            Oh, that's right. Now I remember. But if I recall switchers, a lot of transformer / rectifiers have cutters - rapid on-off switches so the AC power turns into an extremely high frequency signal. It's more AC than AC. Then you step down, then rectify and smooth the signal. Otherwise you need *much* bigger capacitors - your PSU would be bigger than your laptop.

            They shouldn't care about AC or DC in, because they just cut the signal into a jitter. But it's easier to step down if you are already close to the fin

          • Re:Imagine that (Score:5, Informative)

            by Bakkster ( 1529253 ) <.Bakkster.man. .at. .gmail.com.> on Monday June 08, 2009 @07:49AM (#28249725)

            To change the voltage. Historically, it's been hard to change DC voltages in a small, efficient, compact device.

            Bullshit. It's easy to get >80% efficiency with a small Buck Converter circuit, and well designed circuits can get upwards of 95% for some conversions. You know that power supply in your computer? Only about half of it turns the AC into DC. All those voltages you use (12V, 3.3V, 5V, etc) are generated from small, efficient DC/DC converters. It's just a controller, inductor, capacitor, and transistor.

            Don't believe me? How's this for small? [powerconversion.com] And yes, I am an Electrical Engineer, and spent a summer designing a power supply with two DC/DC converters.

            • Re: (Score:2)

              by wisty ( 1335733 )

              He did say "historically". Switchers weren't always so easy to make. There is probably still infrastructure around that predates transistors.

              • He did say "historically". Switchers weren't always so easy to make. There is probably still infrastructure around that predates transistors.

                In this case, history doesn't matter. There is no need for an inverter if you only plan to use the DC component, for example to charge a laptop. I guess the real question is if you want the solar to pump into your normal AC wall outlets, or if you can stick with special use, such as a solar backpack, laptop case, etc.

            • Yeah, it used to be that you had to have a lot of copper wire in a transformer for a power supply to work that converts AC to DC. Now you don't even see that, just a bunch of transistors. Yep, transistors can do almost anything now and they are cheaper than copper. So I don't get why this stuff is so expensive. In the US there must just be small cottage industries making solar setups. They buy the panels for a manufacture that probably has a lot of hand work involved while in Germany they use robotics and f

        • Re: (Score:2)

          by b0bby ( 201198 )

          Houses could be wired to have an AC system (for obsolete equipment, and stuff that needs electric pumps), and a low voltage DC rail (for new stuff).

          The cost for rewiring old houses is prohibitive, and since they're the bulk of the housing stock it would be hard to get momentum for this. But it's nice to dream...

      • Re: (Score:3, Insightful)

        by Rei ( 128717 )

        Second, quite frankly, the technique means crap, because they are inefficient, cheap panels, which makes no sense unless you have a huge roof.

        1. There's no shortage of unused roof space in the world right now. What matters is cost per watt. Make it cheap enough, and it'll be installed everywhere.

        2. Home-scale inverters would be a heck of a lot cheaper if their volume went up 1,000-fold. And that's what'd happen if solar panels that were easy to install on new (or especially existing) homes could be made

        • What matters is cost per watt.

          Cash cost, or the total energy cost of manufacturing, fitting and maintenance? Because the first can be skewed with grants (aka "I pay for your energy"), the second, not so much, no matter how much proponents of solar would like to pretend otherwise.

        • I have a big shortage of roof space on my house, and I doubt solar is going to get anywhere near producing all of my electricity or water heating requirements, so I would have thought that ultimately it is watts per square meter that matters.

      • First, what "little push" would that be? You (quite deliberately) don't say. Second, quite frankly, the technique means crap, because they are inefficient, cheap panels, which makes no sense unless you have a huge roof.

        H'mm, Actually, the cells use only five square meters, which is a tiny fraction of the size of most house roofs. Secondly, while they are "only" 8% efficient, this happens to be as good, if not better, than the greater percentage of solar cells available on the market. (Fact is, most manufacturers are careful to avoid quoting an efficiency figure, but you can work one out easily enough.) Your bitch about the panels being of less importance (cost wise) than the panels would also seem extremely suspect. If t

      • Re: (Score:2, Interesting)

        by FordPrefect276709 ( 1346539 )
        if you have a roof or any other solar exposed surface, go and mount panels to heat water. it's the only reasonable thing to do. solar power is great for low-temp heat harvesting and you don't need expensive (in terms of $ or in terms of resources wasted) controlling electronic. water saves 4.182 kJ per K at no cost & you will save a big lot of $$$ in heating too cold water with valuable electricity or oil! producing electricity from solar power will almost never pay out. and PLEASE: never ever lay t

      • Hurricanes (Score:3, Interesting)

        by JMandingo ( 325160 )

        Here in Florida we have plenty of sun available. However, one prohibitive problem with solar panels is the occasional hurricane. If you have large solid panels installed on your roof, a strong wind will pick them up like a kite and tear them (plus a good chunk of your roof) right off.

        I like the idea of something cheap and flexible because you could either have a system of rolling it up when a storm approaches, OR let the storm have it (like pool screen enclosures) and install a new one afterwords.

    • Re: (Score:3, Insightful)

      by feepness ( 543479 )

      Isn't it amazing how all of these advancements show up when given a little push?

      It really is amazing how they founded a company, got a grant, looked into an area of research, and made a breakthrough all in less than three months.

      I gotta hand it to the administration. I used to think government was inefficient. Now I know better.

    • Re: (Score:2)

      by amn108 ( 1231606 )

      I am not sure I would call it an advancement. I ought to give it the deserved credit though - after all more products is always better. Thin film photovoltaic arrays however have been around for some time.

      Also, Xunlights rolls have 8% efficiency, compared to around 15% for rigid (and heavy) panels you can already buy to install on the roof etc, or even 20% if you've really got the cash.

      The good part is, according to this http://en.wikipedia.org/wiki/File:Solar_land_area.png [wikipedia.org], the black dots represent areas w

      • Re: (Score:2)

        by amn108 ( 1231606 )

        In the post above, it was supposed to read "1 to 3 m^2", but the submit script ate and swallowed my superscripted power value there.

    • Isn't it amazing how all of these advancements show up...

      But they don't show up. Of all the hundreds of news stories of amazing technologies that have appeared on Slashdot over the past ten years, how many can you just go out and buy at Target or Home Depot?

      None.

      Maybe one or two. probably not.

      Any announcement of an amazing technological breakthrough that appears on Slashdot generally stays that. A press release of an amazing technological breakthrough that's going to solve

  • We all heard about how great Nanosolar is, but it's not actually possible to buy any. Will this stuff be any different?

    • They will likely go bust before anyone manage to figure out how to buy their product.

    • Re:Will we actually be able to buy these? (Score:5, Informative)

      by confused one ( 671304 ) on Sunday June 07, 2009 @06:29PM (#28245225)
      100% of Nanosolar's production output is going to large scale (commercial/industrial scale) solar plants. They keep building additional manufacturing capacity but have not saturated the commercial demand. There's no need for them to offer panels to consumers; their business model is quite sound.

      • There's no need for them to offer panels to consumers; their business model is quite sound.

        The quality of their business plan is completely irrelevant to my reaction to my inability to purchase their product.

        • There's no need for them to offer panels to consumers; their business model is quite sound.

          The quality of their business plan is completely irrelevant to my reaction to my inability to purchase their product.

          Sounds like a good business to get into.

        • Re:Will we actually be able to buy these? (Score:5, Insightful)

          by Jeremi ( 14640 ) on Sunday June 07, 2009 @07:04PM (#28245463) Homepage

          The quality of their business plan is completely irrelevant to my reaction to my inability to purchase their product.

          Also, your reaction to your inability to purchase their product is completely irrelevant to the quality of their business plan.

          • Re: (Score:3, Funny)

            by drinkypoo ( 153816 )

            The quality of their business plan is completely irrelevant to my reaction to my inability to purchase their product.

            Also, your reaction to your inability to purchase their product is completely irrelevant to the quality of their business plan.

            Unfortunately, the quality of the irrelevance is that I am unable to react by purchasing their product.

            Er, and, Plan, or something.

  • How much will it cost? (Score:5, Insightful)

    by wjwlsn ( 94460 ) on Sunday June 07, 2009 @06:09PM (#28245071) Journal

    This sounds like a great idea, but it probably isn't the breakthrough that the summary might otherwise suggest. The efficiency of the resulting solar panels, even with triple-junction cells, is still only 8% at most (as stated in the article). At that level of efficiency, the manufacturing process will have to be very inexpensive for these to make sense for the average consumer.

    • Re:How much will it cost? (Score:5, Informative)

      by TD-Linux ( 1295697 ) on Sunday June 07, 2009 @06:24PM (#28245185)
      Cost-per-watt matters much more than density right now (efficiency directly affects density) - look at all the roofs and other potential locations for solar panels. Efficiency isn't the reason they aren't up, it's the high cost. Even 8% efficiency, is still more power than you get out of an asphalt slab.

      • Efficiency isn't a big thing, yet. But as the cost decreases and people want to buy more, they'll need more roof space with a lower-efficiency panel. It's already an issue for larger (commercial-type) installations, where more efficient panels could save space, and thus wiring, mounting, etc.

      • Re: (Score:2)

        by wjwlsn ( 94460 )

        I think maybe you didn't understand me. What I was trying to say was that at 8% efficiency -- if the cost is not significantly cheaper than currently available solar tech -- the investment in these solar panels won't be justifiable for the average electricity consumer, relative to the cost of just buying power from the local utility.

        I agree that cost/watt, over the life of the equipment, is probably the most important factor here. People would happily buy solar tech that was even less efficient than 8%, if

      • Re:How much will it cost? (Score:4, Interesting)

        by physburn ( 1095481 ) on Sunday June 07, 2009 @10:56PM (#28246915) Homepage Journal
        Very true, the cost is more important, solar power is approaching parity with oil and gas, and is supposed to reach it at 5 cents per watt. The article didn't give the price of the roll up solar cells, so i've no idea how close to that it is, but such advances will steadier push the balance of prices into solars favor, which is to happen expected by 2012.

        Solar Power [feeddistiller.com] feed @ Feed Distiller [feeddistiller.com]

    • Re:How much will it cost? (Score:4, Insightful)

      by Karganeth ( 1017580 ) on Sunday June 07, 2009 @06:29PM (#28245223)
      It'll have to be around 40% of the cost of a standard solar cell (since many are around 20% efficient). It doesn't seem much when you consider that these solar panels are extremely thin. The amount of materials needed to create them will be very small and these solar panels are printable. If only they showed us a price we'd know if they were the future or not.

      • In fact, I remember an article here on /., that said, that they are only 1/10th of the price of normal cells. Which makes sense.

    • Re: (Score:2, Interesting)

      by SourPatchKid ( 1571523 )
      There are some on Ebay from a company called Power film Solar and they go for $320 for a 21 watt. I can't imagine this company would be much cheaper. So it is a little pricey for the average consumer.

    • While printing on film is fairly cheap, this is actually a somewhat dated techbology already. TFT technology is older than I am, and a couple of years ago, Danish researchers prooved that they could actually PRINT (using a normal printer and special ink) a solar cell.
      Again, it suffers the same problems that this cell does, that the efficiency is very low. At the same time, the print would ofcourse decay/fade over time. This problem at least seems to be resolved by printing on thin film. Production of the Da

  • Slowly becoming cost-effective (Score:5, Informative)

    by benjamindees ( 441808 ) on Sunday June 07, 2009 @06:17PM (#28245139) Homepage

    Building integrated photovoltaics (BIPV), especially rooftop applications, would be the biggest market for flexible PV technology, Boas says.

    Roofing is a significant cost in a residential structure. Being able to integrate the roofing material with the solar panels can help make photovoltaics cost-effective.

    In Las Vegas, for instance, roofs are made of expensive (and heavy) clay tiles, mostly for aesthetic reasons. These run anywhere from $30-$50 / m^2.

    • Re:Slowly becoming cost-effective (Score:5, Informative)

      by drinkypoo ( 153816 ) <drink@hyperlogos.org> on Sunday June 07, 2009 @06:41PM (#28245323) Homepage Journal

      You can already get adhesive thin-film solar "panels" in widths and form factors intended for application to metal roofing panels (the kind shaped like this: A______A — but the As are open like a V and they overlap each other there.) You put it down on some sawhorses and roll out a big sticker which leaves you with a cord hanging off one end. As you put the panels on the roof, you snap the connectors together, and they all get covered by the roof cap at the end. If the roof cap should get damaged, it's inexpensive and relatively simple to replace, all in one piece, so it provides excellent protection for the wiring. You can walk on it, although that doesn't set it apart from today's high-quality crystalline panels.

    • Re:Slowly becoming cost-effective (Score:5, Informative)

      by veganboyjosh ( 896761 ) on Sunday June 07, 2009 @07:32PM (#28245671)
      Actually, the clay tiles are used in most desert areas not for aesthetics. Well, not directly. They're the material that's been used in that area for hundreds of years. It's cheap, abundant, and easy to work with.

      One more reason they've been the material of choice for so long? They don't spontaneously combust the same way asphalt shingles or other popular materials can.

      /nitpicking.

      • Re: (Score:3, Interesting)

        by account_deleted ( 4530225 )
        Comment removed based on user account deletion

        • Re: (Score:2, Insightful)

          by fractoid ( 1076465 )
          It's because of scale. A decent photovoltaic set can power your house and, combined with a battery bank, make you completely independent from the grid. A solar fired steam plant with a molten salt heat reservoir is only really practical at large (multi-megawatt and up) scales. The other problem with using it in a desert is that you need a good cold source to run an efficient steam turbine, which is why power plants (regardless of source) are generally built near bodies of water. You can get past that with c

        • Re:Slowly becoming cost-effective (Score:4, Informative)

          by benjamindees ( 441808 ) on Sunday June 07, 2009 @09:25PM (#28246363) Homepage

          1) It doesn't fit on a roof. The average roof space per capita is fairly tiny. This is the reason people are most interested in small-scale, high-efficiency, and ridiculously over-priced renewable energy production methods such as solar photovoltaics.

          2) Deserts are actually pretty windy. Tracking mirrors have to be over-built to stand up to the wind and avoid mis-alignment.

          3) Molten salt is high-temperature. High-temperature things could possibly be dangerous. Anything potentially dangerous attracts insurance companies, bands of idiots propped-up by a government that prefers killing people via wars and resource shortages rather than allowing individuals access to useful, possibly dangerous technologies.

          4) Aesthetics. Solar panels are mostly unobtrusive. Tracking mirrors and tanks filled with molten salt are industrial-looking, and thus ugly.

          So the basic problem is that power from molten salt tanks must be produced and sold as a commercial venture. That means it has to compete with coal and natural-gas fired utilities, and still be efficient enough to return a profit. This will basically never happen unless governments tax fossil fuels out of existence.

        • Was there a problem with the tech? So was there a problem? Did I miss something

          The answer to all of your questions: "yes".

          Unfortunately I'm a bit too lazy to dig up the references and specific projects for you right now, but if you do some searching you'll find that this method is still a prototype with problems. Last I saw, it was also only a functional prototype on a very large scale, and the temperatures, engineering, and monitoring involved would place it out of limits of residential applications.

          I'd encourage you to seek out National Geographic's Man Made: Solar Quest. They cov

  • dupe this when i can buy it at HomeDepot or Lowes, Mkay? Thanks

  • Support for vents and pipes? (Score:5, Interesting)

    by ChartBoy ( 626444 ) on Sunday June 07, 2009 @06:38PM (#28245301)
    Big sheets of PV are wonderful when you have big open expanses, but real world roof surfaces have vents, pipes, drains and the like. Rather than play tetris with rigid panels, or even with flexible panels, I'd love to be able to cut an opening in the PV material for each opening and get maximal use of the roof surface.

    Is anyone working on that?

  • Safety (Score:5, Funny)

    by MrKaos ( 858439 ) on Sunday June 07, 2009 @07:05PM (#28245475) Journal
    Solar Power, it's the safest form of nuclear power.

    • Re:Safety (Score:5, Insightful)

      by Anonymous Coward on Sunday June 07, 2009 @08:19PM (#28245965)

      Actually, it's by far the most dangerous. It is completely unshielded, and its ionizing radiation is responsible for thousands of cancer deaths each year.

      • Re:Safety (Score:5, Insightful)

        by Jeremi ( 14640 ) on Sunday June 07, 2009 @10:09PM (#28246631) Homepage

        Actually, it's by far the most dangerous. It is completely unshielded, and its ionizing radiation is responsible for thousands of cancer deaths each year.

        Of course, there is the small detail of it being equally dangerous whether you harvest the power, or not. So we might as well....

        • Re: (Score:2)

          by sorak ( 246725 )
          Maybe the supervillains have the right idea. We can block out the sun and prevent needless cancer deaths.
      • Comment removed based on user account deletion

      • Re: (Score:3, Informative)

        by MrKaos ( 858439 )

        Actually, it's by far the most dangerous. It is completely unshielded, and its ionizing radiation is responsible for thousands of cancer deaths each year.

        ummmm, I'm sure the magnetosphere shields us from the suns radiation.

    • Re: (Score:3, Funny)

      by hedwards ( 940851 )
      Nonsense, that would be geothermal. Compare the rates of burned to death by volcanoes with died of skin cancer, I think the answer is obvious.

  • Options and Choices. Good signs. (Score:4, Interesting)

    by upuv ( 1201447 ) on Sunday June 07, 2009 @08:35PM (#28246063) Journal

    In the last 18 months we have seen numerous announcements regarding solar power generation.

    We've seen advances in
    -Manufacturing speed.
    -Toxic material reductions.
    -Efficiency boosts in rigid cells.
    -New products like this flexible.

    Yah sure solar has issues. But now given a space that may be inappropriate for wind you can now find a solution in solar.

    This is all good.

    Maybe one day industry will be draining it's massive power needs from the residentially power generating grid. This should be more than doable in 20 years.

    ( Next item we need to add to the list of critically needed tech. Water purification and desalination that can be applied in the residential markets. Imagine how much land would open up for crops, settlement, and carbon sinking if we just had cheap and easy to deploy water desalination. )

    • Re: (Score:2, Insightful)

      by jeffb (2.718) ( 1189693 )

      ( Next item we need to add to the list of critically needed tech. Water purification and desalination that can be applied in the residential markets. Imagine how much land would open up for crops, settlement, and carbon sinking if we just had cheap and easy to deploy water desalination. )

      You live in California, don't you?

      I can say with some confidence that my residential area, well over 100 miles from the nearest ocean, is not in any sense bottlenecked on water desalination capacity.

      • Re: (Score:2)

        by smoker2 ( 750216 )
        Yet.

        By catching and holding much of an areas rainfall, and extracting water from rivers you prevent it from replenishing the underground aquifers and the water table drops over time. One day, a field you didn't have to irrigate goes dry. The Columbia river is a shadow of its former self due to demands for irrigation and potable water.

        So be as smug as you like, it will catch up with you.

      • Re: (Score:3)

        by upuv ( 1201447 )

        Nope live in Aus.

        Just have a gander at the globe. You see all that brown land. It's a fare chunk of the land surface. If even a hair of that was made habitable by the simple application of fresh water.

        Just think North Africa could easily become the bread basket for Europe and Africa if it had fresh water. Australia could grow enough potatoes to feed all of the Irish and put Vodka in all of the Russians on the planet.

        Cheap easy to implement desalination would be possibly the most important thing for man k

    • Next item we need to add to the list of critically needed tech. Water purification

      Let me guess... been playing a lot of Fallout 3 [wikia.com] lately?

      • Re: (Score:2)

        by upuv ( 1201447 )

        I live in Aus and no I haven't played any online games in ages.

        ( I take a plot component in Fallout3 is about water? )

  • The lamp in your dome light will put out light pretty reliably from about 6 or 7 up to about 15 volts and is available everywhere, and the automaker probably gets them for a nickel. The LED runs on a narrow voltage range so it needs a power supply which tends to be an IC, two transistors, and a resistor (for limiting current) as well as a PC board, and probably its own enclosure to avoid shorts.

  • Sigh, another technology that will make it someday (Score:3, Insightful)

    by barfy ( 256323 ) on Sunday June 07, 2009 @09:21PM (#28246333)

    Where are the Stanford 10x Li-ion batteries???

    http://news-service.stanford.edu/news/2008/january9/nanowire-010908.html [stanford.edu]

    This ALONE will change everything. From an All day Iphone and netbook. To a Chevy Volt that costs 1/2 as much.

    WHERE IS IT?

  • uh, regular solor cells ARE flexible you retards. it's the glass they get bonded to and the alloy frame they sit in that prevents this.

    i'll bet they are just regular cells with fuck all weather proofing on them and they degrade in 6 months.

  • Well, there is no savings. The incandescent bulb is cheap, cheap cheap. The LED is not. The power to drive the light comes from the battery, which is charged by the alternator. The alternator doesn't care. You can run over 1KW off the stock alternator. The little current required for the incandescent or bulb doesn't matter. So why put a higher cost part in the car? But wait the LED isn't 12v, it is TTL, so you need to convert from what is a 12v-14v wiring harness to TTL levels. If you use a cheap resistor,

    • Re: (Score:2, Informative)

      by Anonymous Coward

      TTL?! TTL has got nothing to do with illumination with LEDs.

      As for running LEDs on 12V, there's an easy solution for that: a single-chip regulator (costs less than LEDs!) and a string of LEDs in series. Easy.
      You need your LEDs, a small PCB to hold it all, the regulator, perhaps a capacitor or two, and an inductor. The LEDs are likely to consume most
      of the cost.

      • The price of the LED's largely dominates current LED lighting systems.
        Usually the LED driver or driver controller will require an inductor, a sense resistor, an input and output filtering cap, and if it's a controller running a lot of LEDs, a FET that's doing the switching. Add 2-3 small resistors and a cap for soft-starting, tying unused dimming options to ground, stuff like that. Most drivers will end up having half a dozen to a dozen parts associated with the driver circuit.
        But the nice thing about a d

    • The alternator doesn't care, but your MPG suffers every time the alternator spins. You can get quite a few more useful HP out of an engine if you remove the alternator completely. And if the rest of your claptrap were true, manufacturers would not be using LEDs in tail lights, dashboard instruments, turn signals etc etc. Less demand means smaller alternator, means more useful power to the wheels, means more MPG.

      As for TTL, bollox mate.
      http://www.rapidonline.com/Electronic-Components/Optoelectronics/Minia [rapidonline.com]

      • No bollox.

        At $9.50 each, you have a very expensive part... Which has integrated electronics to lower the voltage. Just because you can screw it into a 12v socket doesn't mwan its 12v.

        Standard bulbs here are about $3 for a back of two..

        The amount of current contained in one turn of the alternator is enough to light the bulb for quite a while. Your own driving style, inflation pressure and fuel grade will affect your mileage more than the bulbs in your car.

    • Re: (Score:2)

      by amorsen ( 7485 )

      The power to drive the light comes from the battery, which is charged by the alternator. The alternator doesn't care.

      I don't know where you get this from. Electricity is really expensive in cars; small internal combustion engines running at variable speeds just suck for making electricity. If good LEDs were available, cars would switch to them almost instantly.

      Alas, LEDs in the 60W-equivalent range are hard to come by (unless you use multiple LEDs, and that's hard in a dome light).

  • This is so old news it hurts (Score:4, Informative)

    by Aceticon ( 140883 ) on Monday June 08, 2009 @04:30AM (#28248635)

    Companies have been manufacturing and selling thin-film, flexible printed to roll solar panels since at least a year ago.

    For example, check http://www.uni-solar.com/ [uni-solar.com] and http://www.firstsolar.com/ [firstsolar.com]

    The things to keep in mind with this technology:
    - Cheaper manufacturing, partly because the print to roll technology is much more scalable that the processes used to manufacture traditional solar cells, but also because of high silicon prices (traditional solar-cells use a silicon substract just like integrated circuits and thus compete for the same raw materials: before the recession silicon production was insufficient for both needs, so silicon prices where making traditional solar cells more expensive).
    - Lower efficiency (around 9%) versus traditional solar cells (around 15%). Note that some recent advances are likely to increase the efficiency of traditional solar cells even further.
    - Better at generating energy under low light conditions (e.g. in the shadow) than traditional solar cells.
    - There are some questions about the long term viability of some thin-film solar cell technologies since they use rare elements: their price might go higher as production increases since that will also increase the demand for said rare raw materials.

  • Because these panels are flexible, this means you could easily cover round or curved surfaces, like flag or telephone poles. Imagine a wind generator whose support pillar is itself covered in solar panels for a green power double whammy!

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