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Power Plant Fueled By Nut Shells 297

Posted by simoniker
from the don't-have-to-be-nuts-to-work-here dept.
sbszine writes "The Sydney Morning Herald is running an article about a green power plant that runs on the discarded shells of macadamia nuts. The power plant, located in Gympie, Queensland, is expected to reduce greenhouse gas emissions by around 9500 tonnes in its first year of operation."
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Power Plant Fueled By Nut Shells

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  • by Powercntrl (458442) on Thursday September 18, 2003 @05:22AM (#6992632)
    ...sometimes a volt.
  • by Anonymous Coward
    So, all these sunflower seed husks must be good for something. I wonder if we'll get "Mr. Nuthusk" personal portable systems someday.
  • Reduction in Co2? (Score:5, Interesting)

    by zefod (30387) on Thursday September 18, 2003 @05:24AM (#6992640) Journal
    My guess is that they would burn the shells of these nuts, right? This produces carbondioxide, so how does this reduce CO2?
    • It's a trick. It reduces 'potential emissions'.

      It's like when I break into your house and leave gifts. I could have robbed you blind. Aren't you glad I'm such a nice guy?
    • Plants need CO2 while growing, so burning them is CO2 neutral.

      Bye egghat.
      • Re:Reduction in Co2? (Score:5, Informative)

        by zmooc (33175) <zmooc@nOsPaM.zmooc.net> on Thursday September 18, 2003 @05:48AM (#6992723) Homepage
        Wrong. The only thing that matters in this context, is the percentage of CO2 in the atmosphere. While in the long term, burning plants would indeed not introduce any new CO2 into the biosystem. The only problem is that it is generally assumed it takes about 100 years for nature to create a balance between CO2-production ans CO2-consumption by plants. Just compare it to a closed system in a box with a plant and a device burning it's seeds; the plant will consume the CO2 a lot slower than the device can produce it so the CO2-level in the box will definately go up just like a sink will fill when the tap runs faster than the drain can put up with.

        But in the long term it's always better to burn plants instead of oil since burning oil introduces new C into our biosystem while burning plants only raises the C-level in the atmosphere but not in the biosystem.

        By the way, this only works if you assume each burned plant will be replaced by a equivalent plant. Burning more plants means the average age and therefore size of plants will decrease and therefore the amount of C these plants can hold will also decrease. And then even the space that's available for plants is declining.

        • by misterpies (632880) on Thursday September 18, 2003 @06:05AM (#6992764)
          Wrong wrong wrong. A nut grows in a single season. The carbon in the nut can only come from CO2 in the atmosphere. Therefore burning nuts is carbon neutral over a single nut-growing season.

          Similarly, I fail to follow your example of a plant in a box. OK, while the seeds are actually aflame CO2 will be produced faster than it's being absorbed. But overall, the amount of carbon in the system is constant: anything which is not in the plant is in the atmosphere. Therefore so long as you burn the plant no more quickly than it grows, you'll never end up with a higher CO2 concentration than when you started.

          Your argument only applies if you start burning something which has been growing for decades -- eg old-growth forest -- in which case you're releasing CO2 that took decades to remove from the atmosphere. But so long as you burn material grown only over, say, the last year -- eg fast-growing bamboo -- then the net amount of CO2 released into the atmosphere over that year must be zero.
          • Re:Reduction in Co2? (Score:3, Interesting)

            by zmooc (33175)
            Please take a look at this image [zmooc.net] in which I represent two situations in which an equal amount of plants is grown during a season in a closed system. In situation 1 we burn the plants, in situation 2 we just let them be. I assumed the rotting time for such a plant to be 2 years. This clearly shows that the average amount of CO2 in the atmosphere will be lower when the plant-to-CO2-process takes longer. I think it's fair to assume rotting takes longer than storing and burning. If it'd be the other way around,
            • by stephenbooth (172227) on Thursday September 18, 2003 @11:16AM (#6994798) Homepage Journal

              I think you're missing a fairly big hole in your arguement. Burning the nut shells will release C into the atmosphere, so will the rotting process. However burning the shells will mean that you will need to burn less oil and coal (C removed a very long time ago when there was a greenhouse effect in place due to the high levels of CO2 in the atmosphere) so you are reducing the overall amount of C released by putting the inevitable release of C due to the nut shells to use and reducing or eliminating the need to burn oil and coal.

              If we assume that qualtity of C released from the nut shells (N) is the same for both burning and rotting, that the quantity of C removed from the atmosphere growing the nuts (P) is costant in both cases (we are talking about using a waste product of an existing industry here, not about growing the nuts as a fuel source) and the the burning of the nuts will provide the same energy as burning oil and coal that would release a quantity of C we label F then the quantity of C released to the atmosphere (A) will be for each scenario):

              Rotting: A=(N+F)-P

              Burning: A=N-P

              Stephen

          • Who is regulating how many nuts are burned in these plants? Is this a real limit, or just some pie in the sky model the proponents use? Burning is burning. Are you actually saying that plants absorb no carbon from the ground? That is carbon that was locked in rock form and not spread across the atmosphere. And it *is* absorbed by plants. From http://www.sciencenet.org.uk/database/earth/natur a lenvironment/e00077d.html [sciencenet.org.uk]:

            The greatest stores of carbon are believed to be the world's oceans and fossil fu

        • Re:Reduction in Co2? (Score:2, Informative)

          by Disevidence (576586)
          I hate to tell you this, but the shells of the nuts are going to decay anyway, releasing the carbon into the biosphere. So why not speed the process up, and generate some cheap electricity.
          • Re:Reduction in Co2? (Score:3, Informative)

            by zmooc (33175)
            Because, like I said, it's about the % of CO2 in the biosystem which will stay lower if the C is kept in the biomass longer. You're not looking at it as if it's a closed system, while it is (with regard to C, at least).
            • Re:Reduction in Co2? (Score:4, Interesting)

              by WolfWithoutAClause (162946) on Thursday September 18, 2003 @08:37AM (#6993294) Homepage
              The atmosphere and biosphere is not a closed system, because the CO2 is removed from the atmosphere by weathering (CO2 and limestone forms carbonate rocks) and added to the system predominately by volcanic activity and only very much secondarily from human activity (by nearly two orders of magnitude). In addition CO2 is not the primary greenhouse gas, water vapour is far more significant.
        • Re:Reduction in Co2? (Score:5, Informative)

          by famebait (450028) on Thursday September 18, 2003 @06:32AM (#6992844)
          Just compare it to a closed system in a box with a plant and a device burning it's seeds; the plant will consume the CO2 a lot slower than the device can produce it
          What makes you believe that? Are you assuming that the plant produces seeds at a diminishing rate, or that burning a seed releases more carbon than was put into building it? Because something doesn't add up here.

          You are describing a closed system with a net production of carbon. If you have one of those you could be very rich indeed.
          Just like a sink will fill when the tap runs faster than the drain can put up with.
          That's not a closed system.
          The only problem is that it is generally assumed it takes about 100 years for nature to create a balance between CO2-production ans CO2-consumption by plants.
          That's a little out of context. Yes, if you completely cut down a forest, it takes a long time until there is once again the same amount of biomass contained on that area. But we're not _removing_ the ecosystem and waiting for it to return here, we're burning a nutshell in stead of allowing it to rot. The tree is still there, and it doesn't take a 100 years to replace a nutshell. If you burn a billion shells a year and produce a billion too, you have a net emission of zero. You're basically just extracting solar energy, the shells and the carbon are just carriers in the process.

          There would be an minor initial 'cost' in that you're shortening the cycle a little, releasing the carbon more shortly after it's trapped compared to natural decomposition. So you get an initial emission over the first year or two after start up, as the 'cache' of decomposing shells releases its carbon at the same time as new shells are burnt immediately. But after they're gone you'll be running in balance. Or you could avoid that too by imitating nature and storing the shells a couple of years before burning them.
          • Re:Reduction in Co2? (Score:4, Interesting)

            by spektr (466069) on Thursday September 18, 2003 @08:06AM (#6993143)
            Just compare it to a closed system in a box with a plant and a device burning it's seeds; the plant will consume the CO2 a lot slower than the device can produce it
            What makes you believe that? Are you assuming that the plant produces seeds at a diminishing rate, or that burning a seed releases more carbon than was put into building it? Because something doesn't add up here.

            There are two coupled systems: the solid biomass in the soil and the CO2 in the atmosphere. CO2 is transported in both directions at a *slow* rate. Decaying biomass releases a modest amount of carbon into the atmosphere, while most of it is recycled directly by plants and microorganisms. In the same way the plants absorb a modest amount of CO2 back from the atmosphere.

            If we burn biomass then we accelerate the transfer of carbon into the atmosphere. The transport from the atmosphere to the solid biomass is mostly unaffected by this instantaneously (though a higher CO2 concentration may let plants grow faster).

            So, in a short frame of time, burning biomass has the potential to increase the CO2 concentration in the atmosphere. In the long run, the ecosystem will reach a new equilibrium. This equilibrium doesn't necessarily possess the same climatic properties of the equilibrium we experience today.
        • Keep in mind that at one point that C *was* in the biosystem, if it's the pressurized remains of precambrian forests and animals. It's just that the C belongs in compressed contained form on the surface rather than scattered across the atmosphere. Just like O3 is good in the upper atmosphere but bad in the lower atmosphere.

          But the planet itself doesn't care about C or O3 levels...it only matters to the things living on it.
      • So if I burn up half the forests right now you would not mind; the other half will use it anyway, right? I doubt this is true, or the tree huggers would not be hugging so many trees. The fact is, if they are burning they are still causing damage. It's not a "good thing" just because it's "not oil". Don't mix geopolitical with environmental.

        This is like pure electrical cars...someone is burning something somewhere to produce that electricity!! Hyric cars have it right, but we can do better.
        • by egghat (73643)
          Oh come on!

          The article (you've read it, right?) was about burning macadamia nut shells. Which means "waste" used for CO2 neutral energy production.

          What's wrong about that?

          Bye egghat.
    • Re:Reduction in Co2? (Score:2, Interesting)

      by Redmega (641324)
      It doesn't. I think the idea is that the CO2 in the nut shells was fixed by the tree during the growing season - so when they're burnt again, only the same amount of CO2 will be released. As opposed to digging up Coal or Oil which was fixed possibly 1000's of years ago, and won't return by the same process for another 1000. Doesn't make much sense to me; I've always figured massive solar power farms on the moon would solve all of this. How hard can it actually be?
      • I've always figured massive solar power farms on the moon would solve all of this.

        Yeah, so would cold fusion :)

        How hard can it actually be?

        Very. Not to mention expensive, with a break-even point probably measured in *hundreds* of years.

      • by Nihilanth (470467)
        how would you transmit the power back to earth? Pay to have batteries shipped over? Or maybe invent that wireless power supply that i've been hankering for all these years?
      • I think the idea is that the CO2 in the nut shells was fixed by the tree during the growing season - so when they're burnt again, only the same amount of CO2 will be released.

        You silently assume that all the carbon the nut is made of came from the atmosphere. Is this necessarily true? Trees are growing on top of dead trees.
    • by gl4ss (559668) on Thursday September 18, 2003 @05:40AM (#6992700) Homepage Journal
      those same nuts needed the co2 when growing.

      so there's no 'extra' co2 introduced from millions of years back like when you burn oil/coal.

      so it does reduce the total amount of co2 coming to the atmosphere, provided that somebody plants some more of those nuts(and doesn't chop some rainforest/something else that binds huge amounts of it to plant those nuts for few seasons and then chop more of rainforest).

    • Higher usable energy (Score:5, Informative)

      by moscow (68604) on Thursday September 18, 2003 @05:48AM (#6992721) Homepage
      According to ABC Queensland [abc.net.au], Macadamia shells are actually prime material for electricity generation - they burn more cleanly than coal, and produce more energy.

      Of course, natural decay of the shells would release the CO2 in any case.

      • by mpe (36238)
        Of course, natural decay of the shells would release the CO2 in any case.

        The decay process can also produce methane. Which is worst "greenhouse gas" than carbon dioxide.
    • Re:Reduction in Co2? (Score:2, Informative)

      by bernywork (57298)
      It also reduces the requirement on burning coal something we do WAY to much of here in Aus.

      Basically it would also be a comparison in producing the same amount of energy from burning coal vs. macadamia shells.
    • Re:Reduction in Co2? (Score:3, Informative)

      by DrXym (126579)
      Potentially it is carbon neutral, but presumably the nuts need transporting, processing etc. so it isn't really. Still, it is miles better than burning fossil fuels.
  • Nuts (Score:5, Funny)

    by CGP314 (672613) <.ten.remlaPyrogerGniloC. .ta. .PGC.> on Thursday September 18, 2003 @05:24AM (#6992641) Homepage
    The power plant, located in Gympie, Queensland, is expected to reduce greenhouse gas emissions by around 9500 tonnes in its first year of operation.

    In an unrelated story, macadamia nut consumption is up 10,000%
  • by shadowcabbit (466253) * <cx@tBOYSENhefurryone.net minus berry> on Thursday September 18, 2003 @05:26AM (#6992646) Journal
    ...after trying to harness the power of looney, wacky, zany, or crazy, they succeeded only in making use of nutty power.
  • But does anyone know why they chose macadamia nuts? Seems a very strange choice.
    • Because they are processing the nuts there and the shells are a waste product.

      Also they are very tasty!

    • My understanding is they had an existing facility that shells and cans macadamia nuts, and previously the shells were just being discarded as waste product. Someone had the bright idea to use the waste shells as fuel for a power plant. Basically, they just turned an expense (waste disposal) into a profit (electricity generation). And the facility only cost $3 million to create. All in all, I think this was an absolutely brilliant move.
    • by madbastd (632125) * on Thursday September 18, 2003 @05:52AM (#6992729)
      But does anyone know why they chose macadamia nuts? Seems a very strange choice.
      Macadamia trees [crfg.org] are a native plant in that part of Australia, and grow very well. There's a large macadamia nut industry there, which was throwing out huge amounts of nutshell.
    • I would assume there is a great abundance of them. In the region where I live, there is a lot of almond trees and production of candy primarily from these almonds. Of course, the shell is thrown away. Most of the metal, carpentry shops and other small warehouses burn the shell of the almond to heat these places in the winter. The setup is a very tall triangular shaped bin that lets the almond shells fall by gravity into a burner. The shells burn very hot and it's very efficient, or so I am told.

      When I was

  • by thesuperjason (568702) on Thursday September 18, 2003 @05:28AM (#6992656)
    we could develop a plant that converted empty XXXX (local QLD beer) cans into usable power. Now that'd be something! Well, it'd ease my concience anyway...
    • How about burning the gas created after drinking the beer
      Now, how to collect it!
    • > we could develop a plant that converted empty XXXX (local QLD beer) cans into usable power

      It would finally give a reason for XXXX to exist. Unless the stuff you export to the UK is some sort of revenge tactic. 'I got it, Bruce! We'll put kangaroo piss in XXXX cans and send it to England! Those poms will never spot the difference...'

  • by WIAKywbfatw (307557) on Thursday September 18, 2003 @05:30AM (#6992662) Journal
    Nutshell Power in a Nutshell.

    I'm guessing it'd have a monkey on the cover. Or perhaps, sticking with the power plant theme, a picture of Homer Simpson eating nuts.

    I know I'd pay good money for that book.
  • nice prediction (Score:4, Interesting)

    by loraksus (171574) on Thursday September 18, 2003 @05:32AM (#6992674) Homepage
    yes, this assumes that the grid is not already running at close to capacity. . . As we know, it is pretty rare to start up another power plant if there is no need for it. . .
    So the "savings" is kind of like the recording industry's / BSA's claims of "losses", a great way to get rid of nuts though. Has anyone seen "Equilibrium" by the way? ;)

    Granted, it beats burning coal or the many other alternatives, but I suppose gold plating it makes the 3 mill a lot easier to swallow.
    • Well, a few months ago, I was working in the electricity biz in QLD, and I can assure you that they are not nearing their generation limits at the moment.

      However, the power grid is very long and thin (just about everyone lives on or near the coast) and most of the existing generators are not all that conveniently close to the main demand centres, so they sometimes have problems shuffling the power about to get to where it's needed.

      My guess is that this new station will help aleviate that problem.
  • by Moderation abuser (184013) on Thursday September 18, 2003 @05:33AM (#6992680)
    Unlike the thousands of tonnes of domestic rubbish we throw into huge steaming pits every day.
    • You laugh. See this picture [rpacalmonds.com]? See those long piles that look like dirt? Those are piles of almond hulls and shells. See those tiny box-like things lined up next to them? Those are trailers for big rigs. A person would be less than a pixel high in this picture.

      I imagine a plant for processing macadamia nuts would have a similar pile. There is a huge amount of waste in this process. Every nut you've ever eaten was covered by a shell and hull at least as massive as the part you consumed. In large pi

    • Such "energy from waste" plants do exist and are often touted as "green" energy. There are a couple of problems with this. First, when you burn rubbish, most of the heat generated comes from the plastic in the rubbish. Plastic is ultimately made from fossil fuels, so burning rubbish is just a really innefficient way of burning oil, and does nothing to reduce CO2 emmissions.

      It also produces dioxins and a cocktail of other highly toxic chemicals. There are many studies showing that people who live near w
      • by ajs318 (655362) <sd_resp2 AT earthshod DOT co DOT uk> on Thursday September 18, 2003 @08:33AM (#6993270)
        Not true. Extreme heat destroys dioxins. They are often created by partial combustion {think bonfire}. What is basically going on in a fire is two processes. Pyrolysis is the fuel being decomposed into simpler chemicals, almost always incomplete fragments {sometimes even individual atoms} which will bond with whatever is nearest to hand {strictly speaking, nearest to valence electron?} as soon as they cool down enough. Pyrolysis consumes energy in breaking chemical bonds. Oxidation is the simpler chemicals reacting with oxygen. This gives out energy. Oxygen is chemically very horny and also will try very hard to avoid having to share with anything else. The pyrolysis products undergo some further decomposition as the oxygen atoms each try to grab something for themselves. Since the oxidation puts out more energy than the pyrolysis required, the fire stays alight. But you have to put some energy in {typically from a match} to start the pyrolysis, otherwise you would get spontaneous combustion.

        Now, in a bonfire or badly-designed furnace, the pyrolysis products cool and recombine into literally goodness-knows-what and escape before they get a chance to combine with oxygen. This is where incineration can fail. Large lumps of fuel, and mixed fuels, all exacerbate the problems.

        In a well-designed furnace, the fuel is finely-divided and the air supply forced {an unattended fire will tend to produce only as much energy as it needs to stay alight; this may mean partial combustion with great quantities of chemicals being released. A fan requires energy, but MOTN the energy gain from fetter combustion is greater than the consumption of the motor}. If the fuel is very heterogeneous, the pyrolysis phase of the reaction can be completed separately in by heating the fuel in an airless chamber {consuming energy} and the pyrolysis products burned later {releasing more energy than it took to do the pyrolysis}. By adjusting the temperature and pressure you can select whether the intermediate product is a gas, a light liquid like petrol or a heavy liquid like diesel fuel. This has the advantage that you know how long is the longest carbon chain in the fuel for the next stage, and there is no way that the products can contain sny longer carbon chains. The disadvantage is that it distributes the high-temperature processes, thereby creating more opportunities for heat leakage.

        As for the "plastics" argument, it's a red herring. Upstream segregation could be used to separate plastic from the waste being used for energy recovery, if you were really concerned. But I can't see how it would not be better to extract energy from plastic that has already been used for something, than to use up energy burying that plastic in landfill and digging up more fossil fuel just to burn for energy. Over time, as fossil fuels became more expensive, plastics would begin to be made from plants anyway. Not to mention that lanfills also produce dioxins, albeit more slowly, and organic matter in landfill decays to CH4, which, molecule-for-molecule, is a better heat trap than CO2. The real problem is ignorance of the First Law of Thermodynamics. We've already had people bitching about CO2 emissions like they don't know where the carbon in a plant comes from, and if people can't appreciate the First Law as it applies to the tangible form of matter, how can we suppose they can appreciate it as applied to energy?

        Of course, I'm with you about reduction. My ex's daughter was raised in reusable cotton nappies, so will be my niece at least while she is stopping with me. I avoid single-serving packs whenever possible. I wipe my nose on yesterday's T-shirt, and I put my sandwiches straight in my lunchbox without using a polybag {in the absence of a satisfactory explanation as to how wrapping food in plastic saves me from risking cancer by letting it touch plastic}. I don't use sanitary towels either, but only for The Reason That Does Not Count.
    • Insightful? This is about reducing CO2 emmissions using fuel that was previously waste material. How did you come to think it was about mitigating domestic rubbish?
  • Efficiency? (Score:5, Interesting)

    by brucmack (572780) on Thursday September 18, 2003 @05:34AM (#6992682)
    It would be nice to know what the cost efficiency of this plant is... seeing as how this has always been the big problem with "green" power.

    Also, is there any inherent advantage to using macadamia nuts rather than some other biomass?
    • Re:Efficiency? (Score:2, Insightful)

      by WebMasterP (642061)
      I'd like to know too.

      This article is entirely too vague... frustratingly vague.

      The first thing I thought was that they would burn the shells. But, how would that help? You're still putting CO2 into the atmosphere. Maybe the macadamia nuts burn clean?
      • Re:Efficiency? (Score:3, Insightful)

        by cruachan (113813)
        It doesn't matter if you put CO2 into the atmosphere with this process because it's the same CO2 the plant fixed from the atmosphere while it was growing. The net effect of the grow/burn cycle is zero, from our point of view.

        Contrast with Oil and Coal where you're putting CO2 into the atmosphere that was fixed out millenia ago.
    • Re:Efficiency? (Score:5, Insightful)

      by Thomas M Hughes (463951) on Thursday September 18, 2003 @06:58AM (#6992907)
      The main advantage in this case is that they were already growing the macadamia nuts in the area, and they were already shelling them. The shells were then, previously, just being discarded. Because the "fuel" for this power plant was previously considered "waste", the result is much more efficient economically then a lot of things.

      Think of it like this:

      macadamia = shell + nut

      Old equasion:
      profit = sale of nut - disposal of shell

      New equasion:
      profit = sale of nut + electricity generation from shell

      This, of course, assumes that the electricity produced from the shells can be sold at a profit that is greater than the cost of disposing of the nuts. From everything I've heard here, the power plant is relatively inexpensive to construct ($3 million), as such, the cost of electricity generation probably won't be that great. However, we'd need more data to say that for sure.

      As an added bonus, the CO2 output is neutral over a single year. Ie: shell takes 1 year's worth of CO2 in as it grows, we then burn it, and 1 years worth of CO2 is released. Comparatively, coal takes in X number of years (thousands of years ago), we burn it, and it releases it into the atmosphere now, resulting in a gain in CO2 in the atmosphere.

      Keep in mind that this means we won't be powering the entire country with macadamia nut shells. This plant only powers 1200 homes. The brilliant aspect of this is that its powered off of waste that was already present in the region. This would be similar to a facility that produces corn creating a power plant next to it that is fueled by corn husks and the unedible parts of the corn. Its simply just a comparative advantage. Its fuel that you have here and now, so there are little to no transportation costs. Even if another biomass is more efficient, you'd have to transport it to the generation facility, decreasing its overall efficiency.

      Ideally, for something like this, you'd build lots of smaller facilities, wherever burnable bio-waste is produced. 1200 homes here, 1200 homes there, mix it with some solar and wind generation, and other alternative energies, and eventually the fossil fuel habit might be kicked.
  • by CGP314 (672613) <.ten.remlaPyrogerGniloC. .ta. .PGC.> on Thursday September 18, 2003 @05:36AM (#6992685) Homepage
    How much energy goes into getting the nuts out of the shells in the first place? I remember going to a macadamia nut farm in Hawaii once. They had a prize of a lifetime supply of macadamias if you could get a nut out of a shell without using a saw. I tried smashing it with a rock with no luck. Apparently, no one had ever collected the prize.
    • by Anonymous Coward
      The thing is, it doesn't really matter. They're already extracting the nuts from the shells anyway; the shells are therefore a waste product of an existing process. Burning the shells may not return 100% of the energy required to extract the nut in the first place, but it certainly would offset the energy required to extract the nut. Which is nice.
    • How much energy goes into getting the nuts out of the shells in the first place?

      Presumably a lot less than the amount of energy the plant generates by extracting the energy from one, given their supplying energy to the grid, not the macademia nut company.

      They had a prize of a lifetime supply of macadamias if you could get a nut out of a shell without using a saw

      Maybe they use a saw?

    • by deek (22697) * on Thursday September 18, 2003 @06:35AM (#6992855) Homepage Journal
      • How much energy goes into getting the nuts out of the shells in the first place?
      I've visited a macadamia farm, and seen the machine that they use to remove the shells. It resembles something like an engine, with rows of levers catching the nut and compressing it just a few millimeters. The shell is very brittle and cracks completely if you can compress it just a little.

      • They had a prize of a lifetime supply of macadamias if you could get a nut out of a shell without using a saw. I tried smashing it with a rock with no luck. Apparently, no one had ever collected the prize.
      I can't say I'm surprised. I regularly crack open macadamia nuts. Handheld nutcrackers are useless. I've actually broken the nutcracker before I've broken the nut. My method involves an irresistable force and an immovable object (who said that theoretical physics wasn't practical?! 8)) . But seriously, I use a hammer and a rock slab. I literally have to pound the nut a good three or four times with the hammer. And I mean serious swings ... with the kind of force you need to drive a nail. But the nut always gives way, and on rare occasion, the finger too (ouch!).

      Whoever came up with the phrase "a hard nut to crack", obviously worked in the macadamia business.

      DeeK
    • I remember going to a macadamia nut farm in Hawaii once. They had a prize of a lifetime supply of macadamias if you could get a nut out of a shell without using a saw. I tried smashing it with a rock with no luck. Apparently, no one had ever collected the prize.

      My primary school (in Brisbane, QLD) had Macadamia tree in the grounds so I got a lot of practice...

      The shells are damned tough. You DON'T want to use a saw (too much work!). It's difficult to use a (lump/sledge) hammer because you can't hit it ha

  • by Potor (658520) <.farker1. .at. .gmail.com.> on Thursday September 18, 2003 @05:39AM (#6992696) Journal
    How did they get the technology to split the nut?
    • by Mattcelt (454751) on Thursday September 18, 2003 @07:56AM (#6993098)
      Well, basically, they take another nut and shoot it at high velocity at a group of nuts. (This group must be large enough to have a "critical mass".) When the accelerated nut hits the group of nuts, it breaks, sending portions of its innards (the meat, in technical terms) into the other nuts, which break open other nuts, which cause them to release their meat, with each nut releasing its potential energy in an ever-increasing "chain reaction".

      But they need to control this highly dangerous process, so they use a fluid which surrounds the nuts to slow the reaction at the edges of the mass. They looked for a long time before they chose just the right formula, but they've settled on a standard, something physicists call "dark chocolate".

      The major byproduct is a nutmeat-filled candy bar called "Hershey's", named after the scientist/confectioner who invented the process. While highly dangerous to a small portion of the population, most people are only subject to a small subset of detrimental effects.

      In related news, recently the doorways in the plant had to be widened considerably to accomodate the plant's regular staff, who seem to have taken to eating the power plant's byproduct.
  • Thats nothing (Score:5, Interesting)

    by mphase (644838) on Thursday September 18, 2003 @05:39AM (#6992697) Homepage
    Watch this process [discover.com] turn your garbage into oil.
    • ...If a 175-pound man fell into one end, he would come out the other end as 38 pounds of oil, 7 pounds of gas, and 7 pounds of minerals, 12 pounds of nutritious green wafers, as well as 123 pounds of sterilized water.

  • by Anonymous Coward
    The Macadamia nut power idea is cute, but I assume (missed it in the article) that they are just using the local excess biomass. Must be a big Macadamia industry nearby.
  • Reduction in CO2? (Score:2, Interesting)

    by flyingdisc (598575)
    This misses something. This must be a reduction in CO2 relative to conventional power generation. How else can a powerplant reduce CO2 when it is producing it.
    • What is meant is reduction from CO2 gasses produced by burning fossile fuels. Everytime when you burn something that comes from deep beneath the ground the CO2 (and also H20) is added to the biosphere (atmosphere, soil and oceans) of the earth. Plants, trees, and algea use C02 to grow. If you burn them, you do not add CO2 to the biosphere. It is assumed that the increase in CO2 in the biosphere will also lead to an increase of CO2 in the atmosphere. CO2 is a green-house gas, which is believed to increase th
  • by BenjyD (316700) on Thursday September 18, 2003 @05:47AM (#6992717)
    Nearly thirty posts and no Simpsons joke yet? You guys are slipping.

    Mmm ... macamadamia nuts
    • Homer: Awww... 20 dollars!? I wanted a peanut.
      Homer's brain: 20 dollars can buy many peanuts!
      Homer: Explain how.
      Homer's brain: Money can be exchanged for goods and services!
      Homer: Woo hoo!
  • Hello, 1970? (Score:5, Interesting)

    by heironymouscoward (683461) <heironymouscowar ... TBSDom minus bsd> on Thursday September 18, 2003 @05:53AM (#6992734) Journal
    This is the scene. I'm a young boy, 8 years old, in Dar-es-Salaam, capital of Tanzania. On the horizon sits a squat building with a tall tower, belching some kind of gray-white smoke.

    "Mummy, what's that?"
    "It's a power plant, Heirony"
    "What does it burn, Mummy?"
    "Caschew nut fruits, Heirony"

    The caschew nut grows as a small nut on a huge fruit which is rich and oily. For each of those tiny caschew nuts, a fruit weighing perhaps 500gr is grown, harvested, and then discarded.

    In Tanzania in 1970, and probably still today, these fruits were dried and then burnt for power. Glad to see that some third-world technology had finally made it to the rich west.
    • In Brazil the cashew fruit juice is made into a somewhat mouth-puckering, pale yellow beverage called cajuada that is very popular. The juice is greatly watered down and heavily sugared, like making lemonade; it is typically sold in open diners from those lemonade dispensers that show the beverage constantly being circulated like a fountain. I was told that the caju (cashew) fruit is poisonous unless it is cooked first. (Other popular beverages are freshly pressed sugar cane juice served with ice, and th
      • Re:Hello, 1970? (Score:3, Interesting)

        by ColaMan (37550)
        yeah , most sugar refineries have their own power system for the cane trash. In fact, one of the refineries locally to me (Mackay, Queensland) also has the capability to put it's excess power onto the grid. Don't know how often they do it though.
  • ... produce energy. You can burn old tires, waste, nearly anything that doesn't explode, and you can gain energy out of it. So where is the breakthrough here? Of course it is amusing to produce power out of nuts and their shells (i think the only fraction against it are the squirrels). Is there any ecological or economical advantage over producing power out of other sources?
    • I think the point is that it has been built by a company that processes macadamia nuts. So they were producing the shells anyway. Now they are using the shells to power their plant and also to export power to the national grid. Seems very cool to me.
  • by Docrates (148350) on Thursday September 18, 2003 @06:15AM (#6992795) Homepage
    So, in a Nut shell, there's a lot of energy.
  • on Wednesday that in the future, cars could be powered by hazelnuts. That's encouraging, considering an eight-ounce jar of hazelnuts costs about nine dollars. Yeah, I've got an idea for a car that runs on bald eagle heads and Faberge eggs.
    Source [saturday-night-live.com]
  • A problem with many "green" power plants is that they are constructed with materials that were produced burning fossile fuels. If this were not the case, "green" power would be cheaper than "fossile/dirty" power. It often comes down to the point that "green" power plants are just very expensive batteries, and it would not surprise me, if in many cases the are actually wasting energy.
  • Ow my gawd! (Score:3, Funny)

    by varjag (415848) on Thursday September 18, 2003 @06:42AM (#6992872)
    Do they really burn O'Reilly Nutshell series there? Fascist pigs! As if they couldn't power it with 'The Road Ahead', 'Mein Kampf' or Clancy books instead..
  • by Zog The Undeniable (632031) on Thursday September 18, 2003 @07:17AM (#6992960)
    There are biomass power stations in Europe that use willow as a fuel. Willow trees grow very quickly and, as has been done for centuries, can be "pollarded" to remove the last year's growth for fuel without killing the tree. These plants are CO2 neutral. over the timespan of a year. Biodiesel [biodiesel.org], which works in the majority of new diesel cars, is also CO2 neutral because it comes from quick-growing crops such as soya beans.

    All this makes more sense than GWB's hydrogen economy, which needs electricity to make the hydrogen. As electricity generation is about 30% efficient, there's not much point in using biomass to produce hydrogen for fuel cells - you might as well stick biodiesel straight in the car.

    • by panurge (573432) on Thursday September 18, 2003 @07:45AM (#6993059)
      In fact, why aren't we trying to replace 3rd world drug crops with biomass fuel crops? Support poor farmers, reduce dependence on imported oil, benefit the population as a whole rather than the drug cartels and the oil company executives...oops, there went the economies of Florida and Texas. Why don't I think it's going to happen? Because biomass is good for the public, but it's bad for the bushes.
    • And here I thought biodiesel wasn't efficient because of the land mass involved to produce enough of it. I was told that was just for fueling the cars and didn't take into account the energy to create the cars.

      You're telling us that it's more efficient to create the cars and then fuel them directly with biodiesel. Someone is way off on their efficiency figures here.
  • Infrastructure (Score:3, Interesting)

    by bludstone (103539) on Thursday September 18, 2003 @07:48AM (#6993068)
    Im suprised noone has mentioned this yet.

    America and the worlds infrastucture is currently dependant on oil production. This allows the individuals who have the oil to gain tons of power through the sales of billions of dollars worth of black sludge.

    We dont generally like these people much. (Racism not-withstanding, politics in the middle east are a huge mess.. but we all knew this)

    Why dont we just sweep the rug out from under them and switch our infrastructure to something like this? I mean, america already produces enough food to feed the world, the waste of this production is a byproduct that, basically, goes to waste.

    Build these power plants in America. The oil companies can do it, profit greatly, and at the same time, destroy the source of funds for our "Rivals."

    This post is from a compleatly political perspective, and many of the ideals do not exactly reflect my own beliefs.
    • Food production is one thing in terms of land mass efficiency, production of fuel is another. I have been told that if we didn't do anything with the USA except grow stuff for fuel we might possibly be able to produce enough for Europe to use. But that assumes we don't use any ourself (no room for roads or cities, it would all be farm land).

      Is this what you propose?

  • Wow 1.5MW (Score:2, Informative)

    by edison490 (551402)
    Holy cow! A whole 1.5MW. Lets see, thats about enough to power 100 homes!
    • Oh yeah, that's impressive. Then you have to figure in the energy required to gather the nuts and process them. I'm guessing this thing isn't nearly as efficient, clean and wonderful as they make it out to be.
    • Holy cow! A whole 1.5MW. Lets see, thats about enough to power 100 homes!

      Are you running your own aluminium smelting plant at your house or something?!!
  • by nate (592)
    a bunch of nut cases...

    (a power plant run by nut cases? :-)
  • by ONOIML8 (23262)
    "a green power plant"

    How does it make any difference to the story what color the plant is?
  • Using the data from a news article (http://www.bizjournals.com/pacific/stories/2001/ 0 1/08/daily2.html), this is how many acres of macademia nuts you need to have to keep this power plant active:

    50 million lbs is about 20 million kilos. For about 20.000 acres, that means you produce about 1000 kilos of nuts per acre per year. Assume that the shell is about the same weight as the nut (probably grossly overestimating, but can't find data on it), so you'd produce 1000 kilos of shell per acre, per year.

    The
  • "'New Scientist' magazine reported on Wednesday that in the future, cars could be powered by hazelnuts. That's encouraging, considering an eight-ounce jar of hazelnuts costs about nine dollars. Yeah, I've got an idea for a car that runs on bald eagle heads and Faberge eggs."

    -- Jimmy Fallon, Weekend Update
  • Seriously.

    My partner actually went to high school there, but the one time I went there (her school mate was getting married about 5 years ago) I got chickenpox from the brides kid brother... damn buffets...

    I didn't get chickenpox like you presumably had as a kid. I was 22, and I got chickenpox so bad that I was covered inside and out.

    After a few days getting rapidly worse, I ended up "drifting off" one evening over dinner while babbling incoherently, so my partner and friends thought they probably bet

  • Allergy concern? (Score:3, Insightful)

    by sphealey (2855) * on Thursday September 18, 2003 @03:49PM (#6997299)
    I used to clean out gas turbine engines by dumping ground walnut shells in the air intake. Loads of fun, and it smelled like Good Humor Toasted Almond Bar in the vicinity for quite a while afterward.

    But I now know several people with fatal allergies to tree nuts. So I wonder - what is the effect on any allergic people nearby of vaporizing nut shells and injecting the vapor into the atmosphere?

    sPh

  • by allanj (151784) on Sunday September 21, 2003 @09:48AM (#7017148)

    I've had a stoker furnace in my home for 5 years now, and it has burned a variety of waste products with great success:

    • Hazelnut shells
    • Compressed sawdust
    • Cherry nucleus shells
    • Olive oil nucleus shells
    • Wheat - unfit for consumption for various reasons
    • "Oilcakes" - byproducts from animal protein feed production
    • Pea byproducts

    So in short, YOU can do this too - but probably not in metro areas. Get a stoker furnace, a form of storage, contact some of the local farming industries around and start heating your home with other people's waste products - safely and very economically.

    Lots of farming industries produce big amounts of waste, and most of that can be converted into biofuel simply by drying and sometimes crushing/shredding.

    Or get a wood shredder and go shred the wood from trees that have fallen down in storms/hurricanes/whatever hits your region the most - many people will gladly let you remove their fallen trees, and you can heat your house very economically in this way.

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