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Biotech Science

Photosynthesis May Rely On Quantum Effect 234

Posted by kdawson
from the good-exitations dept.
forgethistory sends us to PhysOrg for a summary of new research suggesting that the near instantaneous energy transfer achieved by photosynthesis may rely on quantum effects. From the article: "Through photosynthesis, green plants and cyanobacteria are able to transfer sunlight energy to molecular reaction centers for conversion into chemical energy with nearly 100-percent efficiency. Speed is the key — the transfer of the solar energy takes place almost instantaneously so little energy is wasted as heat. How photosynthesis achieves this near instantaneous energy transfer is a long-standing mystery that may have finally been solved."
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Photosynthesis May Rely On Quantum Effect

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  • by Anonymous Coward on Friday April 13, 2007 @08:37AM (#18717507)
    I wonder if ferns ever look at us and laugh saying that non-quantum-sourced energy is so 3 billion years ago.
    • by slughead (592713) on Friday April 13, 2007 @09:36AM (#18718225) Homepage Journal
      I wonder if ferns ever look at us and laugh saying that non-quantum-sourced energy is so 3 billion years ago.

      Maybe so, but then some herbivore eat a thousand of them, we eat a hundred herbivores, and we're the benefactor of all their magic!

      If humans were photoheterotrophic or photoautotrophic, we wouldn't have enough energy to do much more than sit there sulking like a stupid fern. One of the sad realities of a creature like Swamp Thing [imdb.com] (an apparent photoautotroph) is that he wouldn't really be able to move quickly at all. It'd be very easy for some cow to walk up and start nibbling on him (oh sweet irony). Adrienne Barbeau would have to dump his ass for something higher on the food chain like an amoeba.

      Adrienne Barbeau was hot in Swamp Thing. You really want to give that up just so you can have quantum-enhanced solar power? Wait, that does sound pretty cool.
      • I have not seen Swamp Thing, but it is entirely possible that light may not have been the creature's sole energy source. Also, perhaps the creature did a lot of lying around soaking up energy so that it had reserves that would allow it to move around when it needed to.
        • I have not seen Swamp Thing, but it is entirely possible that light may not have been the creature's sole energy source.

          The Swamp Thing was a plant elemental, it probably drew energy direct from the Green rather than relying on its own surface photosynthesis. That would allow it to tap energy from the whole plant life of the earth; easily enough for its purposes. Still, there is something faintly ridiculous about a hero powered by sunlight; such an idea would never fly.

          • Re: (Score:2, Funny)

            by Caelynd (566349)
            Tell that to Birdman. :}
            • Tell that to Birdman. :}

              Now that's impressive. I set up a feed-line about how a hero powered by the sun would never fly, I'm expecting to hear about Kal-El and Kryptonian physiology and Earth's yellow sun and so forth. My congratulations, then, for finding the truly geeky option :-)

      • by kabocox (199019)
        I wonder if ferns ever look at us and laugh saying that non-quantum-sourced energy is so 3 billion years ago.
        Maybe so, but then some herbivore eat a thousand of them, we eat a hundred herbivores, and we're the benefactor of all their magic!
        If humans were photoheterotrophic or photoautotrophic, we wouldn't have enough energy to do much more than sit there sulking like a stupid fern.


        Hey, be nice to our existing photosynthesis plant underlords! They are the ultimate green pacifist liberals. Would you allow ot
        • by jafuser (112236)
          They are the ultimate couch potatos.

          Especially these guys [wikipedia.org].

          PS: It's odd that until now I never noticed what a potato plant looks like, even after all these years of consuming their delicious tubers.
  • Knowing a possible mechanism is important, yes, but that's a long way from having a workable implementation of the method that is useful in a technological sense.
    • by Svartalf (2997)
      That very thing thing [stuff.co.nz] may well have occurred anyhow.
    • by Zeinfeld (263942) on Friday April 13, 2007 @08:56AM (#18717699) Homepage
      Knowing a possible mechanism is important, yes, but that's a long way from having a workable implementation of the method that is useful in a technological sense.

      All interactions at the atomic level are quantum effects. A photon can only interact through quantum effects. The statement in the article is totally meaningless.

      We have known that photosynthesis is a quantum effect since Einstein's paper on black body radiation.

      • More to it than that (Score:5, Informative)

        by Lockejaw (955650) on Friday April 13, 2007 @09:13AM (#18717905)
        When a photon strikes a chlorophyll, it adds its energy to an electron, allowing the electron to escape from its atom (previously known quantum mechanics). It was previously thought that the electron would then go bouncing around between chlorophyll molecules until it found a pheophytin molecule (slightly different chlorophyll). Once it hits that molecule, it activates an electron-transport chain (a similar process happens when burning glucose in a mitochondrion).
        TFA suggests that the hopping uses quantum superposition to traverse the chlorophyll molecules more quickly. When the traversal reaches the pheophytin, the superposition collapses into that single state which found the pheophytin.
        • by arodland (127775)
          Or in other words, photosynthesis is enabled through a larger-scale quantum effect than we previously thought, and we may just know which one.
        • Re: (Score:3, Interesting)

          by jakosc (649857) *
          To clarify, it's not the electron itself that traverses the chlorophyll molecule(s), but the energy of the electron (somewhat analogous to kinetic energy transfer in Newton's Cradle [wikipedia.org]). See also (Resonance Energy Transfer [wiley.com])
    • by DrWho520 (655973) on Friday April 13, 2007 @09:20AM (#18718015) Journal
      Yes, but while knowing the mechanism netted someone their PhD (or some PhD their tenure,) a workable implementation will net some company billions of dollars. Nearly 100% efficient solar cells? Yes, please. Pass the chlorophyll over here.
      • by Rei (128717) on Friday April 13, 2007 @10:59AM (#18719427) Homepage
        Well, that's only part of the story. The original capture loses very little energy...

        1) If and only if the photon is of the proper energy. In general, during solar energy conversion of all kinds, you require a certain amount of energy to kick an electron out of the pigment. Less than that energy, and nothing happens. More than that energy, and the excess is wasted.

        2) This only applies to the original photon capture. The total process of turning solar energy to sugars in plants is about 35%. Due to losses for biochemistry, the overall system is very inefficient -- usually just 1-2% in most crop plants, and a fraction of a percent in non-crop plants. Sugarcane is exceptionally high at 8%, still well below most silicon cells.

        Now, dye-based cells *are* in development. The key for them is not that they're very efficient (they tend to be very inefficient), but that they should be very cheap to produce (no silicon refining needed). Of course, a few companies (such as Nanosolar [nanosolar.com]) are working on commercializing high-efficiency dye-based cells. I read nanosolar's main patent at one point; basically, the efficiency problem with most organic solar cells is an uneven distribution of electron donors and receivers that leads to most of the electrons being wasted. In Nanosolar's case, they build a crystalline scaffolding that the dye gets embedded into at regular intervals, then dissolve the scaffolding.
        • by TheLink (130905)
          Well the stuff self-builds and self-repairs, so I wonder how well the tech will actually do when you factor all that in.
  • I was thinking about this just the other night, strange coincidence. There are probably a lot of functions like photosynthesis that rely on quantum effects. One of them might be the idea of consciousness. Consciousness may not be so easily explained without taking into account quantum effects. If self awareness is enabled through some sort of quantum effect, imagine the philosophical implications.
    • by thefirelane (586885) on Friday April 13, 2007 @08:47AM (#18717603)
      I'm sorry, please clarify: did you actually say anthing in that post?
      • by MightyYar (622222) on Friday April 13, 2007 @09:22AM (#18718059)
        I believe he said, "I'm high."
        • Re: (Score:2, Insightful)

          by SatanicPuppy (611928) *
          Sad but true. I even have a philosophy degree, and people talking about consciousness make me want to slap them. Meat needs stimulus/response; we react when stuff happens around us. Meat also needs fuel and replication, which requires a certain amount of introspection and planning...This is internal equivalent of stimulus/response. Our brains are chock full of stim/response, and the sum of them works out to be what we call "consciousness".

          Nothing mystical about it. While I do believe that stuff on a quantum
          • by MightyYar (622222)
            Oh, now you've done it - you've gone and made someone's meat angry.
      • by Plutonite (999141) on Friday April 13, 2007 @10:31AM (#18719017)

        I'm sorry, please clarify: did you actually say anthing in that post?
        Maybe he did. The philosophical problems raised by the fact that your mental activity, at the lowest "unobserved" level, is the product of a naturally probabilistic (yet determined upon observation)state, is not good. The idea posits that the concept of free will is actually achievable, if your recognition of that will can somehow be excluded from the entanglement process which renders macro-scales like Schroedingers cat irrelevant.

        Just kidding. I will leave now.
    • I don't know about consciousness, but in his novel Blue Mars [amazon.com] (last book of the Mars trilogy), published a decade ago already, Kim Stanley Robinson made use of research that suggests that memory relies on a quantum effect.
      • by meringuoid (568297) on Friday April 13, 2007 @08:59AM (#18717731)
        I don't know about consciousness, but in his novel Blue Mars (last book of the Mars trilogy), published a decade ago already, Kim Stanley Robinson made use of research that suggests that memory relies on a quantum effect.

        Would that mean that attempts to upload human minds to computers would fall foul of the no-cloning theorem? Such constraints on the duplication of quantum information would have interesting effects on philosophical problems of identity.

        • Re: (Score:3, Insightful)

          by eraserewind (446891)

          but in his novel Blue Mars
          You mean you actually finished it? :)

          Red Mars was good, but by Blue Mars, I gave up partway through thinking I really don't care about these people or their dumb politics.
          • by AJWM (19027)
            I gave up partway through thinking I really don't care about these people or their dumb politics.

            That's about the way I felt about Red Mars, and I wasn't even reading it but listening to the book on tape while commuting. Actually more the soap operas than the politics. Maybe if I'd been reading it I could have just skipped those bits.

            (That's what I did with the Chronicles of Covenant that somebody once gave me. Read the beginning and ending bits where he's in the real world, and skipped over the stupid s
        • Even if you had to duplicate quantum information to copy a human mind, it wouldn't prevent upload. We already do quantum teleportation (moving the quantum state of one system to another remote system).

          It would prevent backups or duplicates, though.
      • Did that erase me :)?
        • Re: (Score:3, Funny)

          by meringuoid (568297)
          It erased you, but the data in storage stayed in place. Your neurocircuitry rebooted and launched a new instance of the consciousness process, which loaded in the existing memories seamlessly. You just think you're the original you.
    • by CmdrGravy (645153) on Friday April 13, 2007 @08:55AM (#18717693) Homepage
      Was there any specific quantum effect you had in mind or did your spell checker mysteriously substitute the phrase "quantum effects" for the word magic ?
      • Re: (Score:2, Funny)

        Was there any specific quantum effect you had in mind or did your spell checker mysteriously substitute the phrase "quantum effects" for the word magic ?

        Maybe his spell checker uses quantum effects!

      • Was there any specific quantum effect you had in mind or did your spell checker mysteriously substitute the phrase "quantum effects" for the word quantum effects ?


        Hey! Mine keeps doing that, too!
    • by C10H14N2 (640033) on Friday April 13, 2007 @09:05AM (#18717785)
      None that weren't already stated in numerous terms thousands of years ago in virtually every culture.
    • In one of the various debunkings of What the *bleep* do we know they cover that the neuronal activity in your brain is way too big to be affected by the very small quantum strangenesses that come up. On average they have no effect on your thinking.
    • Re: (Score:3, Insightful)

      by DigiShaman (671371)
      It's quite possible given that think in terms of probability rather than absolutes even through our resulting probable answer borders on an absolute factual answer. Perhaps this is why we have such hard time processing mathematics in our head, yet not art or concepts.
      • We process mathematics seamlessly in our head. How else do you thing you are capable of running to catch a moving ball? The trouble is that is is too seamless. It's not accessible to our higher functions as a set of subroutines with a well documented API.
        • by simm1701 (835424)
          Maybe the EU could help with that...

          "God, we are fining you 3 million Euros a day until you provide fully documented APIs for all neural functions"
        • Ah, but what about the accuracy? We can keep making corrections to the position of our hand right up to impact. We've got good feedback systems, but the 'algorithm' itself need not be very precise at all. Perhaps, in your head, sin(x)=x all the time.
    • by mattpalmer1086 (707360) on Friday April 13, 2007 @09:16AM (#18717933)
      Why do you need to invoke one mystery to "explain" another? I can't see why consciousness "may not be so easily explained without taking into account quantum effects". What particular things about consciousness seem to indicate quantum effects to you?

      Other people have proposed this before, but present a theory of why quantum effects may be necessary. Roger Penrose makes the argument that we can compute things that a Turing-style computer could not compute, so something else must be going on. His proof that some things we do cannot be done by a Turing style computer isn't exactly accepted though, and no-one seriously believes that the brain works in this way in any case.

      Also, consciousness is not the same thing as "self-awareness". Is a dog conscious? Is it self-aware? What about a rabbit? When I dream, I'm not usually self-aware, but there's some sort of consciousness there. What about phenomena like blind-sight, where a person is self-aware, but unconscious of visual information, even though they can access that information by guessing remarkably accurately, just without any direct consciousness of it. Does this mean that these supposed quantum-consciousness effects have broken down only for information originating in visual centers, but keeps working on all other information?

      Of course, coming from quantum theory, there is the Copenhagen Interpretation which places a special status on the 'observer' - but no-one has managed to define what an observer is, or whether they must be conscious or not.

      • Roger Penrose makes the argument that we can compute things that a Turing-style computer could not compute, so something else must be going on.

        What things can we compute that a Turing machine cannot?

        • I can't remember his precise arguments (his book Shadows of the Mind goes into this).

          It has something to do with Godel's proofs - something along the lines that you can't prove something to be true or false inside a particular system, but since we as humans can see that something is true/false nevertheless, so we must be doing something different.

          I don't think the argument holds up very well myself (we can apply lots of different systems, for one thing, we aren't limited to only one), and I am sure I am som
      • by K-Man (4117)
        I may have seen a .sig about that somewhere.
      • by juuri (7678)
        It's only a "mystery" because we just don't understand quantum interactions well enough yet to describe them in detail.

        I always find it interesting (not directed at you) that people assume it's some crazy wacko replacement for religion, etc... when someone suggests that our minds might actually be linked to something outside ourselves. Is this really so hard to believe? That in our becoming conscious perhaps something happens, behind the scenes, say some sort of entanglement across some tightly coiled dimen
    • by Lane.exe (672783)
      Actually, there's lots of good reasons to think that we don't need any sort of physical explanation for consciousness at all, philosophically. It wouldn't be very philosophically interesting if we could reduce the philosophy of mind to quantum physics, because it wouldn't be philosophical, capisce?
    • Consciousness may not be so easily explained without taking into account quantum effects.

      Penrose suggested as much, in his book The Emperor's New Mind [wikipedia.org]. However, this theory is not regarded as serious by any neuroscientists that I am aware of; chemistry and electricity/magnetism is supposed to be able to account for brain function, according to them.

      If self awareness is enabled through some sort of quantum effect, imagine the philosophical implications.

      Actually, the real philosophical implications come f

    • You might want to go to Salzburg this summer to attend the Quantum Mind [sbg.ac.at] conference. You'll find a number of top physicists, a few philosophers, some famous mathematicians, and at least one anaesthesiologist [quantumconsciousness.org] (hey, you don't know what you've got till it's gone).
    • Re: (Score:3, Interesting)

      by denoir (960304)

      There are probably a lot of functions like photosynthesis that rely on quantum effects. One of them might be the idea of consciousness. Consciousness may not be so easily explained without taking into account quantum effects. If self awareness is enabled through some sort of quantum effect, imagine the philosophical implications.

      It's called the Orch-OR theory [wikipedia.org] and is a popular object of ridicule amongst neuroscientists. While consciousness is a very active field of research and there is still much to be d

    • Consciousness may not be so easily explained without taking into account quantum effects.

      Consciousness can be easily explained in three words: It's an illusion. Well, okay, one of those three words is a contraction.

    • There are probably a lot of functions like photosynthesis that rely on quantum effects.

      Like, say, "Color" (or more accurately, radiative/absorbtive wavelength) in general, a completely quantum phenomenon.

      TFA does a poor job of mentioning this, but the fact that plants use quantum effects doesn't exactly count as a "new" discovery. Only the level of detail of our understanding of the transfer lacks completeness.

      To put the "newness" of this discovery another way (FTA):

      This wavelike characteristic can e

    • I was thinking about this just the other night, strange coincidence. There are probably a lot of functions like photosynthesis that rely on quantum effects. One of them might be the idea of consciousness. Consciousness may not be so easily explained without taking into account quantum effects. If self awareness is enabled through some sort of quantum effect, imagine the philosophical implications.

      The Answer is No. although the braind and it's compnents are all physical objects in this universe, that are the
    • by rmdyer (267137)
      "Consciousness may not be so easily explained without taking into account quantum effects."

      On the one hand you are right, on the other you are wrong.

      There have been many books that proposed the idea you are dwelling on. http://www.google.com/search?hl=en&q=Penrose+quant um+mind&btnG=Google+Search [google.com]

      One of them "The Emperor's New Mind", by Roger Penrose, looks into this closely and comes to the same conclusion. However I would be quite surprised if conciousness "actually" boils down to a single physic
    • Whether the mind is mediated through quantum effects or not is mostly irrelevant. All turing equivalent machines are fundamentally, well, equivalent. It doesn't matter what hardware they're on. Quantum consciousness would make no difference in the kind of algorithms the brain can run, it would only affect the mundane issues of implementation.
  • by Waffle Iron (339739) on Friday April 13, 2007 @08:48AM (#18717615)
    ... it's also been discovered that *all* physical phenomena may also rely on Quantum Effect.
    • by Gospodin (547743)

      Yeah. I mean, who would have guessed that a chemical process in which energy from light causes atoms to bind in different ways could have anything to do with quantum mechanics? Crazy!

    • by Carewolf (581105) on Friday April 13, 2007 @09:17AM (#18717943) Homepage
      Well, except gravity.
    • by JDevers (83155) on Friday April 13, 2007 @09:19AM (#18717983)
      Maybe a better summary would be that the energy transfer in photosynthesis is handled by a very long lived wavelike electronic quantum coherence. Regardless of what everyone on /. thinks, this is a pretty big deal. Suggesting something is likely or even almost certain is not the same thing as proving it.
  • by RobertB-DC (622190) * on Friday April 13, 2007 @08:57AM (#18717711) Homepage Journal
    I can't seem to find the link (Google is not friendly today), but does this perhaps justify the researcher who postulated that the sense of smell comes from something akin to detecting nuclear resonance, not a simple chemical interaction? I recall that one detractor said that his theory was as outlandish as saying that food was digested in the stomach via tiny nuclear reactors. But it explained many things that didn't make sense otherwise -- like why cyanide smells like almonds.

    He's apparently gone on to success in the perfume industry.

    Someone find the link... this is driving me nuts.
  • I don't think I really understand what that article is going on about. It seems to be saying that there is something which recieves the sunlight and something else which is the molecular energy. Between these two there are numerous ways of transferring the sunlight energy but some are better than others and that each route is simultaneously probed by both sides until the best one is found which is then used for the energy transferrance.

    Is that even close to whats being described here ?
  • Oh boy. (Score:4, Funny)

    by Rob T Firefly (844560) on Friday April 13, 2007 @09:14AM (#18717911) Homepage Journal
    This explains why the hedge in my yard wasn't doing so well until it was temporarily taken over by the spirit of a wise and charming fern from the future, which corected everything that was wrong in the hedge's life before moving on to my neighbor's lawn ten years ago.
  • by Atraxen (790188) on Friday April 13, 2007 @09:15AM (#18717923)
    The summary is slightly misleading, but this disconnect has big implications for the reader's understanding (imho)...

    I can name plenty of chemical reactions that are complete on the femtosecond scale, and while speed helps, that's certainly not the whole picture. What matters is how mismatched the energy levels between the reactant and the product are. When transitioning between energy levels, either energy is transferred out of the system by nonradiative release (heat), luminescence, photofragmentation, or transfer to a chemical partner - this last case is what the article is referring to. Getting to an energy level which can react is going to result in a heat deposition for at least some photons because any photon of a higher energy than the reacting state must deposit some of that energy just to be able to react at all.

    http://www.monos.leidenuniv.nl/smo/basics/images/j ablonski.gif [leidenuniv.nl] Unfortunately, this scheme doesn't show photofragmentation or energy transfer to another molecule, but I'm in a rush so it'll do.

    The squiggly lines show possible heat depositions - the molecule starts in the ground state, absorbs a photon (the yellow up arrow), then relaxes to the excited state. This excited state then does whatever it's going to do. If 100% of the time under a set of conditions (i.e. a quantum yield of 1.00), the excited molecule follows a particular pathway we call that perfectly efficient. In the specific example of photosynthesis, this means that all of the absorbing chlorophylls transfer the energy along the photosynthetic pathway (I'm lumping all the subsequent processes together here). It does not mean that 100% of the energy got transferred along the way - there will always be some photon that deposits more energy than the reacting state has, meaning some energy will be converted to heat.

    In short form (if you didn't feel like reading all this): efficiency in this case refers primarily to how often the molecule dumps its energy into photosynthesis instead of all to heat, luminescence, etc. It's not referring to the energy throughput, as some photons will always be an imperfect energy match, and the extra energy will end up as heat.
  • Let me be the first to welcome this new research as more than a wacky discovery concerning quantum effects. If we can figure this out, which seems to be the case, imagine the efficiency of future solar cells.
  • 100% efficiency (Score:5, Informative)

    by 140Mandak262Jamuna (970587) on Friday April 13, 2007 @09:19AM (#18717989) Journal
    Some half witted reporter's failed attempt in dumbing down a routine research paper.

    Yeah, sure the energy transfer efficiency is 100% for every photon that participates in the reaction. But of all the photons falling on the leaf, hardly 2% of them participate in reactions. Some gets reflected, some gets absorbed without any reaction. Even solar cells have better energy conversion efficiency than plants. Really. As for quantum effects, almost all the photo reactions are quantum mechanics. They have to be. The film camera emulsion has greater percentage of photons participating in reaction than chlorophyll.

    • by Eccles (932)
      The flaw in your argument, though, is that plants don't have conversion efficiency as their overriding goal. As long as it's good enough to keep the species propagating, the plants won't develop greater efficiency. A human-built equivalent, however, would be targeting higher output, and thus might get more out of the process.

      Moreover, a plant-derived solar cell might be cheaper and easier to produce, essentially growing itself rather than requiring high-grade silicon, etc.
      • Re:100% efficiency (Score:5, Interesting)

        by 140Mandak262Jamuna (970587) on Friday April 13, 2007 @10:43AM (#18719177) Journal
        I am not arguing that the research is worthless or that it might some day create Organic photocell. Infact I tried to make a joke about Organic Light Absorbing diodes yesterday in the LED thread and mangled it and got modded down as troll. It would be great if we could unlock the secret of photosynthesis and understand why its efficiency is so low ( less than 2%) so that we can develop more efficient organic cells. My only complaint was that, the summary is very misleading, talking about 100% efficiency.

        But one thing we should also realize is that, nature has not produced a more efficient photosyntesis process. Plants do not use their energy for mobility. Just to grow. Growth is limited by other resources like minerals and water. So there might not be additional survival value in developing a more efficient photosynthesis process. But still we should be open to the possibility that 2% efficiency is probably the maximum for photosynthesis, using water+co2, producing C12H22O11 (sugar) and oxygen.

    • I know we are far from this, but I dream of the days where we (humains) will be able to build "cells" which can use the light energy to transform the CO2 to O2 in a similar way of what are doing plants, but with a huge yield! Each time I see breakthroughs like this one (the better we understand, the better we can copy) and those dealing with solar cells, I think about that!
      • Fine, but you're the one in charge of sweeping up all of that carbon dust they'll produce.
      • Not far at all. I too am stumping rooting for solar energy and transitioning the world eventually into using sustainable resources. The nature paper is a serious research piece, of interest to academia. Some reporter tried to play it up and ended up mangling it.

        My dream is just humongous mechanized cow stomachs. Large digesters that take in basic plant bio mass, weeds, corn stalks and other basic plant material on one end, chop them up and grind them using steel blades, passing them on to chambers filled

        • by LilGuy (150110)
          Then what do you do with the gigantic amounts of methane in the atmosphere? Something tells me that might have a greater effect on Earth than the large amounts of CO2 we're pumping out.
          • The whole idea of the scheme is to produce fuel. Methane is the fuel. And when it is burnt as fuel the carbon will end up in the atmosphere. But that carbon molecule was very same carbon molecule extracted by the plants from the atmosphere. So the whole scheme is carbon neutral. One way to harvest solar energy is to build solar cells and produce electricity. Another is to let the plants do the job of collecting the energy and concentrating it and then we harvest the plants and extract combustible products o
      • by jafuser (112236)
        Something I didn't know until recently myself is that plants don't convert CO2 to O2. They convert water into O2 [wikipedia.org] and the CO2 becomes biomass [wikipedia.org]. I love learning something that's the opposite of what I thought I knew. =)
  • 100% (Score:3, Informative)

    by fermion (181285) on Friday April 13, 2007 @09:23AM (#18718067) Homepage Journal
    I must take issue with the 100% efficiency. Efficiency, as I know it, is a ability to convert stored energy into useful work. I know of no engine, artificial or natural, that can do this with 100%, which is of course prohibited by the known laws of thermodynamics. In particular, I have seen photosynthesis calculation that set the efficiency of photosynthesis as low at 3%. Even in the simplistic case, it appears that 50-70% of the energy in the process of photosynthesis.
  • Consider the findings of that (sorry forget the name) scientist who was working on biologically evolved electronic circuits. He discovered the bizarre circuits that resulted were sometimes more efficient than human-designed onces, but very hard to figure out. In particular he discovered the circuits sometimes made use of electromagnetic coupling to other parts of the circuit that didn't seem to do anything, and also found they sometimes only worked in narrow temperature ranges.

    Considering the amount of time
  • Old news, George Lucas figured this out 8 years ago.
  • Quantum tanning sun beds being the new craze in tanning...
  • lands space ship in anarctica and eats people.
    Sound like the plot of a movie.

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