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Power Plant Converts Fruit and Veggie Waste Into Natural Gas For Cars 118

Posted by samzenpus
from the mr.-fusion-II dept.
Zothecula writes "Some readers might remember the Mr. Fusion unit in Back to the Future that Doc Brown fills with household garbage, including a banana peel and some beer, to power the iconic time-traveling DeLorean. While we're still some way from such direct means of running our cars on table scraps, researchers at Fraunhofer have developed a pilot plant that ferments the waste from wholesale fruit and veg markets, cafeterias and canteens to make methane, which can be used to power vehicles."
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Power Plant Converts Fruit and Veggie Waste Into Natural Gas For Cars

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  • by Kenja (541830) on Friday February 10, 2012 @12:51PM (#38996319)
    Lots (around 40%) of harvested fruits and veg' rot in the field because the US consumer wont buy imperfect produce. Seems like a lot of potential fule out there.
    • by Tekfactory (937086) on Friday February 10, 2012 @01:00PM (#38996439) Homepage

      The Parent post everstates the case, a lot of imperfect produce becomes tomato sauce, potato flakes, strawberry puree, applesauce, carrot juice, etc.

      There is a lot of agricultural waste, some scratch and dent from retail, and a LOT of uneaten or wasted food from restaurants.

      I expect there are some enzyme or bacteria treatments that can cause this mash to release more starches or sugars before the fermentation phase begins.

      • by gnick (1211984) on Friday February 10, 2012 @01:08PM (#38996585) Homepage

        I don't know how common it is, but a lot of the produce that isn't sold in my local market is donated to local animal shelters. And yes, many consumers prefer the artificially colored/waxed/preserved stuff that is so much prettier than the rest, but I can't believe there's anything like 40% "waste".

        • by ackthpt (218170) on Friday February 10, 2012 @01:26PM (#38996785) Homepage Journal

          I live in the middle of an agriINDUSTRY area. Most of the agricultural waste is left to rot in the fields. To bring it to some place where it could be processed into fuel would consume fuel. Further, much of this waste is recycled into the soil by insects, worms, fungi and bacteria to become fertilizer for the next crop (lest the soil become exhausted.)

          It's a neat idea, but you can use any hydrocarbon waste for this process - cardboard, paper or wood scraps.

          • Well, methane is a greenhouse gas more potent than C02. Also I believe its relatively clean burning itself compared to cardboard, paper, or wood scraps.
          • by bigmo (181402) on Friday February 10, 2012 @02:07PM (#38997235)

            Actually high cellulose content products don't work much at all. You need a high nitrogen content material (poop is the preferred material, ideally bird stuff because it contains the urine as well). There is a particular ratio of carbon to nitrogen that works best and by using various combinations of poop and different vegetable matter you get a mixture that gives the most methane and the least CO2. Vegetable leaf matter by itself will work, slowly, but produces a much higher CO2 to methane ratio so is not very useful for combustion. I assume that actual fruit and vegatables have higher nitrogen content than the leaves.

            I built a few methane digesters in the 70's and I can tell you that it's not as easy as it sounds to actually produce useful amounts of methane. There is a lot of continuous mixing that has to happen or thick viscous mats form and keep things from working right. This consumes energy. You also can't really compress methane much without using more energy to compress it than you get out of it.

            Of course if it's armageddon and you have lots of pig poop & crazy midgets to run things, this could actually work.

            • At the industrial scale these problems can be conquered with modern technology. Cellulosic ethanol is readily achievable, far more efficiently than (for example) nuclear fission, and what's left over from that process can be made into methane or plastics.

              At the home scale, though, you're right. Until the patents wear out on the microbes, biodigestion of cellulose is corporate territory.

          • Most of the agricultural waste is left to rot in the fields. To bring it to some place where it could be processed into fuel would consume fuel.

            Dr. Diesel invented his engine so that it could be fueled by the crops it tended. The first demonstration engine ran on peanut oil. Fueling your vehicles is a marginal overhead cost when you're generating vehicle fuel.

            And if it's all carbon neutral who cares?

      • Agreed because there are always people looking to make a buck like with "baby carrots" [wikipedia.org].
    • Does it rot in the field, providing fertilizer for the next generation of crops and thus reducing the overall costs due to the fact so much artificial fertilizer doesn't need to be used? It isn't waste if it is actually being used for something.
      • by ackthpt (218170) on Friday February 10, 2012 @01:29PM (#38996819) Homepage Journal

        Does it rot in the field, providing fertilizer for the next generation of crops and thus reducing the overall costs due to the fact so much artificial fertilizer doesn't need to be used? It isn't waste if it is actually being used for something.

        Yes. The stalks, top leafs, roots, unripe or spoiled produce becomes food for the next crop, usually some other crop in a rotation. There's a lot of science behind this, too, as some crops enrich the soil, f'risnstance with Nitrogen, for the next crop which is more dependent upon it (usually something leafy) as an example.

    • by CastrTroy (595695)
      But when they rot in the field, the nutrients go back into the soil. If you plan on collecting all this fruits and vegetables, in order to capture the gases from them rotting, you also have to have a plan for returning the compost back to the fields. Not saying it's impossible, but can you get more natural gas from these things that it takes to transport them back and forth between the field wherever the gas is harvested?
      • by Dasher42 (514179) on Friday February 10, 2012 @01:26PM (#38996773)

        Unfortunately the chemicals that industrial agriculture uses interferes with the nutrient cycle that you're thinking of. Because everything other than the plant of interest is treated as something to be killed off with insecticides, fungicides, etc., the soil microbes are killed off, and the survivors are in an imbalanced ecological state which means that they're more likely to act in ways not helpful to the crop. It all leads back to dependency on oil-based fertilizers and pesticides while the soil is little more than a medium to hold the plant upright.

        Otherwise, your solution would fit right in.

        • "Unfortunately the chemicals that industrial agriculture uses interferes with the nutrient cycle that you're thinking of."

          Nice, general statement, unsupported by fact. Your post reflect old techniques, not modern farming.
    • And that is a reason why we cannot optimize the use of our resources. For the most part wasted food when decaid will just produce carbon back into the atmosphere anyways why not get some energy out of it first.
    • by jamstar7 (694492)
      This is nothing new. People have been using biogas in India for ages. I first learned about it over 30 years ago. The Indians use mostly manure, but any organic material can be used, the more plant products you use, the more biogas you get.

      There's a book from 1980 called "The Mother Earth News Handbook of Homemade Power" that goes into it (and other 'green' technologies that work well on small scales) that goes into greater detail. You can find it for 4-5 bucks on bookfinder.com
    • by Khashishi (775369)

      There's plenty of waste at every stage of production. Just look through a grocery store's dumpster or compactor some time. You'll be amazed at what goes in there.

    • the US consumer wont buy imperfect produce

      Judging by my experience in the USA, this is categorically untrue. US consumers will happily tolerate vegetables that taste of (slightly) crunchy water. What they won't buy is vegetables that look imperfect. Imperfections in the taste and texture are fine.

  • Rather than using the methane in cars would be to run it directly into an electrical generation plant. More efficient. Local landfills are collecting the methane, one is uses it to power generators and the other uses the methane to heat city schools.
    • by ackthpt (218170)

      Rather than using the methane in cars would be to run it directly into an electrical generation plant. More efficient. Local landfills are collecting the methane, one is uses it to power generators and the other uses the methane to heat city schools.

      A friend of mine has designed landfills for Natural Gas production and recovery -- peak production in 50 years, with a life span of about 100 years. Not huge amounts, but as you say, sufficient for a small community or a local industrial park is possible with the proper planning.

      Much more of this can be done, if people would get their community leaders to plan how waste is processed and disposed of, rather than the out-of-sight-out-of-mind most people adopt.

    • I've seen a number of projects like this.

      I've seen one landfill with a couple of 1 MW generators selling electricity to the grid. Another, sells the gas to the nearby village for use for heating the community centre.

      Most recently, I've seen one where the landfill gas is captured and used to fuel the garbage trucks. (Diesel/CNG dual fuel).

  • Master Blaster

  • I'm sure the power plant requires fuel to process the food, so is it realy practical? Besides, how is this any better than using Corn or Suger Cain for fuel, that's already being done.
    • It is better because it converts just about anything, including waste biomass we already generate. With corn and sugar based fuels, whole crops needs to be grown (and probably subsidized) to meet the modern demand for fuel. Ethanol and other biofuels have already been shown to be not quite as cost-effective as originally hoped, but with this system, we can start harvesting landfills for fuel.
    • Fermentation is a very passive process as far as the plant is concerned. Very little extra energy is introduced into the system. Once the energy is exttracted the leftovers can probably be used as a livestock feed like many distilleries do with their dried mash.

      Plus were also looking at a source material feedstock if you will that comes from waste that already exists, not Corn and Sugar Cane that would otherwise be feeding people and keeping the prices of those goods at a reasonable level.

    • Depending on the plant, when consumption is low during the night, there may have to be some power dissipators on site to keep the power plant load up at some minimum for it to keep regulation. Any method that uses that extra base power at night that isn't just wasted as heat would be a good thing. Storage is the most obvious solution and batteries aren't the only way to store energy. Pumping water up into a tower, heating some tank of well insulated molten salt (for using the heat later), or in this case p
    • I'm sure the power plant requires fuel to process the food, so is it realy practical? Besides, how is this any better than using Corn or Suger Cain for fuel, that's already being done.

      Better idea is to use ALL of the GMO Corn and Soybeans for fuel until it's used up, so people and animals won't have to eat food that makes them sick. By the time the GMO crops are gone, we'll have enough honeybees to fertilize the crops.

    • I'm sure the power plant requires fuel to process the food, so is it realy practical?

      All energy producing industries consume energy. Coal and uranium don't mine themselves, gas doesn't pump itself through the pipeline and purify itself. Electrical generators not only use electricity to energize the generator windings, but also electricity loses energy by heating the transmission wires whenever you move it around. Don't even get me started about battery losses.

      The trick is to get more energy out than you

    • by DaveGod (703167)

      Because the corn input is valuable, having alternate uses, and costs money. Waste is... Waste. It's a problem and people pay you to take it away.

  • by Anonymous Coward

    Great idea, maybe we should expand this.

    Lets pile all our waste in a big pile, or dig a hole and "fill the land", a "landfill" if you will.
    We should seal it so it doesn't contaminate groundwater of course.

    Then as it ferments and releases methane we could install a venting system and collect or use all that methane for years!

    Oh wait, they've been doing this for decades.

  • Cars powered by fruit farts. Technology at its finest.
  • by lazarus (2879) on Friday February 10, 2012 @01:02PM (#38996489) Journal

    My preference is to consume the fermented fruit matter prior to the generation of methane.

  • Land fill methane (Score:5, Interesting)

    by flyingfsck (986395) on Friday February 10, 2012 @01:03PM (#38996493)
    Methane gas is recovered from many land fill sites. Nothing new to see here, please move along.
    • by Kozz (7764)

      Methane gas is recovered from many land fill sites. Nothing new to see here, please move along.

      I suppose you're right. And I don't know much about such things, but at various landfill sites I've seen this methane being burned off -- a big 'ol stack with a big flame, just like a monster-sized candle. What is it about the methane coming from landfill sites which prevents it being used for generating electricity? Politics or science?

      • What is it about the methane coming from landfill sites which prevents it being used for generating electricity? Politics or science?

        Economics. It's just not worthwhile.

      • by roc97007 (608802)

        At the site closest to me, it doesn't appear to be either collected or burned off, but just released into the air. And I seem to remember it's not the methane that smells bad, it's the other gasses produced (ketones? I don't remember anymore) but it sure do stink.

        I haven't lived in the SF Bay Area in many years -- does the ground at that outdoor arena in Mountain View still spontaneously burst into flame?

      • What is it about the methane coming from landfill sites which prevents it being used for generating electricity? Politics or science?

        Economics driven by politics.

        It takes an imperial arse-load of money to convert a landfill into a power plant. It'll be more profitable to use that money to build a coal-fired plant, since you can entirely ignore any negative social consequences (such as dwindling fertility and rising cancer rates). It's cheaper to pollute... because of politics. We don't charge polluters f

        • It takes an imperial arse-load of money to convert a landfill into a power plant. It'll be more profitable to use that money to build a coal-fired plant, since you can entirely ignore any negative social consequences (such as dwindling fertility and rising cancer rates). It's cheaper to pollute... because of politics. We don't charge polluters for the damage they do to the taxpayer, so there is incentive to pollute.

          Sorry, in European units that would be a metric fuck-tonne of money. For Americans, a standa

    • Yeah, it's not excatly cutting edge research, even rural Indians have been using it for decades.

      http://www.youtube.com/watch?v=zjFybVIggDs [youtube.com]

  • I can do something with my dinner-smuggled hoard of kale and okra.

  • I believe this will really take off when they start genetically engineering bacteria to be efficient fuel producers. I believe that bacteria engineered to produce hydro-carbon fuel will be the power source of the future.

  • by Krater76 (810350) on Friday February 10, 2012 @01:42PM (#38996975) Journal

    ... Doc Brown fills with household garbage, including a banana peel and some beer, to power the iconic time-traveling DeLorean. While we're still some way from such direct means of running our cars on table scraps...

    The Mr. Fusion only powered the Flux Capacitor not the DeLorean. The DeLorean still ran on gasoline and is why Marty gets stuck back in 1885 when the arrow pierces the gas tank.

    • by Hillgiant (916436)

      You raise an interesting point. With 1.21 gigawatts on tap, why didn't Doc Brown put in an electric drive?

      • by Khashishi (775369)

        I'm pretty sure the 1.21 GW is only needed over a brief pulse, not longer than the duration of a lightning stroke. The 1.21 GW certainly isn't available for use continuously.

        • by will_die (586523)
          If the Mr Fusion could not do continuous power in that range then what is its use in the consumer marker? I guess it could be producing less power and charging some batteries.
  • ...but isn't this the thing I've known since my childhood as "biogas"? What's the difference?
  • because the volume of methane from vegetable waste will make a huge difference on our dependence on foreign oil.

    ...However, it's not a bad idea for a survival or deep backwoods technique, if the process scales down reasonably well. Not sure I can consume that much fruit, though.

  • Why?!?! Why are we still burning things to make things go!?!?! This is the epiphany that hit me the other day. We, as a species have been burning stuff for heat for MILLENNIA! It is so bad now that we are affecting our climate. I don't care how "clean" it is we have to stop burning stuff to get energy. PERIOD! We have to stop supporting research to produce more "burning stuff" alternatives. It's the WRONG DAMN DIRECTION! Tidal, wind, solar that's where we need to go. We have a 4 billion year supply of ener
    • by Khashishi (775369)

      Your use of PERIOD makes your argument that much more persuasive. Why should we stop biofuel research? Because you said so. PERIOD.

      • Ummm, maybe because biofuels, although renewable as a source of combustion still produce carbon byproducts that are harmful to our environment? Lower emissions, sure, but not zero and still being burned in engines that are at best 50% efficient at turning that burned fuel into useful work. So, yeah, still bad. Still wrong direction.
        • by Khashishi (775369) on Sunday February 12, 2012 @02:52PM (#39012337) Journal

          Carbon from renewable sources moves in a cycle. The carbon dioxide that is released by burning plants is absorbed by growing plants. Carbon, being an element, can't be created or destroyed except in nuclear reactions (something plants aren't capable of doing), so there can be no net carbon release from renewable processes. The reason why fossil fuels contribute to carbon dioxide release is because fossil fuels represent stored carbon over millions of years, from an epoch when carbon dioxide was more prevalent in our atmosphere.

  • http://en.wikipedia.org/wiki/Biomass_gasification [wikipedia.org]

    There was just recently a show that talked about this, which were common back in the day. They used to be used on tractors & old auto mobiles. By burning wood ( or anything combustible) they can produce a diesel alternative.

    I can't be more specific because I'm not really knowledgable of how it works, other then the "no shit you can do that" moment watching the host on the tv run a generator from burnt trash / wood.

    http://en.wikipedia.org/wiki/Biomass_gas [wikipedia.org]

  • "Fraunhofer"

    There ended my interest in the process... the Fraunhofer Gestapo will be checking to see if your using approved waste....NO THANKS!

    Their antics over MP3 is absolute BS.. NO I do NOT recoginize IP, trademark, license, copyright, or any other of that BS. Its just another reason why I won't travel to Germany again. Would love to go stand at the Brandenburg Gate and compare it to when I was there last and AK47 wielding soliders were poised on top, and would love to get Diebels Alt direct from the b

  • There's one major difference, which I'm surprised that I have to point out to a slashdot audience: fusion releases a whole lot more energy than decomposition and burning. Like, orders of magnitude. So to compare this to the Mr. Fusion unit in BTTF is quite misleading. It may seem odd to use a car analogy in a story about cars, but I'm going to take a stab at it. This is like rolling a log down a hill and claiming that you've invented the Ferrari. :)

  • Will a commercial launch be in time for the four heads of lettuce i bought from Costco four weeks ago?
  • by Misagon (1135) on Friday February 10, 2012 @08:20PM (#39001829)

    Where I live (Stockholm, Sweden), there are many households that have done this for years and the amount is growing.
    Households throw their food waste in special paper bags and put in separate bins. The contents of these are then collected and processed into methane at a factory.

    The incentive for housing cooperatives and households to join the program is that collection of food waste is free while collection of ordinary garbage is not. There should be less amount of normal garbage and thus the cooperation's garbage costs would be reduced.

  • if it's just fruit and vegetables, I wonder if distilling them for ethanol could be more efficient than rotting them for methane.

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