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Power Science

Dept. of Energy Rejects Corn Fuel Future 596

eldavojohn writes "The United States' Department of Energy is stating that corn based fuel is not the future. From the article, "I'm not going to predict what the price of corn is going to do, but I will tell you the future of biofuels is not based on corn," U.S. Deputy Energy Secretary Clay Sell said in an interview. Output of U.S. ethanol, which is mostly made from corn, is expected to jump in 2007 from 5.6 billion gallons per year to 8 billion gpy, as nearly 80 bio-refineries sprout up. In related news, Fidel Castro is blasting the production of corn fuel as a blatant waste of food that would otherwise feed 3 billion people who will die of hunger."
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Dept. of Energy Rejects Corn Fuel Future

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  • by WindBourne ( 631190 ) on Thursday March 29, 2007 @09:24PM (#18538063) Journal
    They (like sugar cane) all grow in a 2d space. In addition, a log of energy goes into growing corn and sugar. In addition, these crops are basically batched. You may plant and then lose it all in the end.

    Instead, ethanol and bio-deasil will come from algae or other microbes. The simple fact is that it allows for a continual stream of fuel as well as feeds on our waste. Finally, the amount of fuel that it uses is a fraction of regular crops.

    Have to laugh at what castro is saying. There is plenty of food for the world. The issue is one of distribution. Correct that, and we could cut back on crops.
  • I would like to know (Score:5, Interesting)

    by rolfwind ( 528248 ) on Thursday March 29, 2007 @09:30PM (#18538123)
    How come aren't there any diesel hybrids available? They should provide even more mpg than a prius.

    While I'm thinking about it, why aren't the car engines run like the train engines, with the diesel motor running at a more or less constant rate refueling the batteries that run the electric motors that actually turn the wheels - the diesel engine could be much smaller than normal because it won't have to peak to provide power - just a nice steady constant - wouldn't even have to be a normal 4 stroke engine - it could be a stirling engine that is highly efficient but has problems speeding up - though Ford managed to get it's 0-60 speed down to 17 seconds while experimenting with alternate engines during the 70s oil crisis - making it's marriage to this application ideal.

    Any thoughts on this? I admit I don't have much knowledge in this area and probably missed something very basic that is wrong with the idea.
  • Why not? (Score:3, Interesting)

    by Runefox ( 905204 ) on Thursday March 29, 2007 @09:40PM (#18538185)
    I mean, when you eat corn, it's pretty much in one end and out the other, anyway, right? Just make everyone in America eat a cob of corn every day, and let the sewage treatment plants separate the fuel from the... Well, you know.
  • Correct (Score:5, Interesting)

    by jeevesbond ( 1066726 ) on Thursday March 29, 2007 @09:59PM (#18538347) Homepage

    Ethanol is not the way forward, the BBC has an interesting article [bbc.co.uk] on this, some excerpts:

    The grain required to fill the petrol tank of a Range Rover with ethanol is sufficient to feed one person per year. Assuming the petrol tank is refilled every two weeks, the amount of grain required would feed a hungry African village for a year

    Much of the fuel that Europeans use will be imported from Brazil, where the Amazon is being burned to plant more sugar and soybeans, and Southeast Asia, where oil palm plantations are destroying the rainforest habitat of orangutans and many other species.

    Using ethanol rather than petrol reduces total emissions of carbon dioxide by only about 13% because of the pollution caused by the production process, and because ethanol gets only about 70% of the mileage of petrol

    Food prices are already increasing. With just 10% of the world's sugar harvest being converted to ethanol, the price of sugar has doubled; the price of palm oil has increased 15% over the past year, with a further 25% gain expected next year.

    So it seems the right decisions are being made here. I'm quite suprised as I thought lobby groups were already springing up around so-called 'green fuels', I've seen some suspicious adverts for ethanol fuels on Canadian TV recently.

  • by G4from128k ( 686170 ) on Thursday March 29, 2007 @10:01PM (#18538359)
    Think about the total amount of food grown and the land used to grow food. The average person eats about 2000-2500 kCal per day in food. The average person consumes about 36,000 kCal per day worth of oil (just oil, not including coal, nat gas, etc.).

    Is the Earth big enough to provide 15-20 times the current food production level of biofuel-grade plant material? And if we plant more energy crops won't we be planting less food crops?

    The US will be fine, but any one who eats food grown on land that could be used to grow an energy crop will see higher food prices.
  • by dbIII ( 701233 ) on Thursday March 29, 2007 @10:16PM (#18538475)
    There is a lot of work going on with ethanol from cellulose. I think that is the answer for consumption in a lot of places instead of some "pork" project to keep a powerful lobby group even happier. I find it bizzare that this group already has enough power that it has Americans getting fat on expensive corn syrup instead of cheaper sugar, but perhaps it's also because I personally don't like the taste. It makes sense for Brazil to make ethanol from sugar cane, but it's a bit more difficult for a colder and drier climate to make it from corn.
  • by WhiteWolf666 ( 145211 ) <{sherwin} {at} {amiran.us}> on Thursday March 29, 2007 @10:22PM (#18538519) Homepage Journal
    I've read about a Mini Cooper design that used a hybrid motor. It was an excellent design, with a gasoline generator powering 4 electrical motors which were located in each wheel hub.

    Here's the link: http://www.leftlanenews.com/hybrid-mini-offers-640 -hp-0-60-in-45-seconds.html [leftlanenews.com]

    640 hp, 0-60 in 4.5 seconds, 160 hp per wheel-motor, and a 3 prong plug-in-the-wall adapter for charging the batteries up.

    Cool, huh?
  • Re:Its about time (Score:4, Interesting)

    by jfengel ( 409917 ) on Thursday March 29, 2007 @10:28PM (#18538573) Homepage Journal
    I'm all for figuring out that corn isn't a miracle for anything except winning votes in Iowa, but where did you get the idea that potatoes require "next to no fertilizers"? I grow potatoes and you have to fertilize the bejeezus out of the things or you end up with cute little micro-potatoes.

    More data:

    http://ohioline.osu.edu/hyg-fact/1000/1619.html [osu.edu]

    Potatoes are still better than corn; for all I know you're right that they're the most efficient. But I just wanted to point out that fertilizers are still going to be necessary.
  • by John Courtland ( 585609 ) on Thursday March 29, 2007 @10:30PM (#18538585)
    I've posted this before, but for a very long time I've wanted to take an inline 6-cyl diesel, turbo it, and jam in into a regular RWD vehicle like a Supra. Then I'd replace the transmission with a large alternator, and have motors all the wheels, or if I can't make the fronts work, just the rears. I'd have to write some custom software to keep the engine running at an efficient speed for the alternator and electrical load, instead of trying to meet perceived fuel flow for mass air, throttle position and exhaust richness. Alternators can achieve 94% efficiency, with some hitting 98% (but that's in a lab, I'm sure it's not that good in reality), and turbo diesels are the most efficient HC engines that I'm aware of at that scale. I wonder if anyone has ever tried this.
  • by lordmatthias215 ( 919632 ) on Thursday March 29, 2007 @10:31PM (#18538599)
    One thing I've heard brought up by universities down here in Texas and Louisiana is a plant called Energy Cane- similar to normal sugar cane, but much more aggressive and much more energy dense. From what I understand the stalks grow over twice the size of for-food cane, and its relatively easy to grow. I say we take a look at utilizing things like that in some parts, at least down in the Houston area (home of Sysco Sugar) where the sugar industry has been hit hard due to artificial sweeteners. Take whatever land that hasn't been converted to suburb yet an get a pilot program going.
  • by Red Flayer ( 890720 ) on Thursday March 29, 2007 @10:32PM (#18538611) Journal
    There are several smaller producers out there who use cane sugar. Jones Soda is switching over [nwsource.com].

    Here's [google.com] the froogle results for cane sugar sodas.

    They are available if you look.
  • > Algae essentially grow in 2d too. They only grow in the plane that the sun shines. Once you have an algae soup, only the top few cm get any light.

    There is an engineering solution around that problem. I recommend you check out Solaroof [solaroof.org], which is (much more than) a circulation system in which the algae-full water from a tank is pumped and circulated over the roof of a greenhouse. The idea is that the algae don't need permanent sunlight, but can rather be "activated" with short exposures to it, and then sent to the bottom of the pool, where they can continue with their metabolic cycle.

    I have met the guy in a pub, and he made perfect sense. This may not be an industry worth setting up in Sweden, Siberia or New England, but I think it would be more than feasible in very sunny, semi-desertic places like you can find in Australia, Southern Spain, Morocco, Israel, Mexico...
  • by thorkyl ( 739500 ) on Thursday March 29, 2007 @11:06PM (#18538875)
    flame me if you will....

    You may joke about the "demonstrations" all you like.
    me -->

    89 F-350 super crew
    7.3 liter
    B-100 for the last 20,000 miles
    Get 15% more HP
    Get 20% more torque
    Petro Diesel is currently $2.71 per gallon where I live
    I can buy B-100 for $2.50
    I make it for $1.21 per gallon
    I use no fossil fuels in its production.
    I use only the oil itself to render the oil (oil feed heater)

    All it takes is the gumption to do it and the willingness to tell big oil where to shove it.

    As for the crop on my farm, they are not for sale to the government as subsidies.
    Nor do I sell to anyone that is not local.

    So no whining about the lack of food, grow your own and stop buying from big business
  • by dbIII ( 701233 ) on Thursday March 29, 2007 @11:12PM (#18538927)
    I find it bizzare that you are using expensive corn syrup in your carbonated drinks at all instead of cheaper sugar - but that's protectionism for you.

    On a better note there is commericial cellulose based ethanol production going on in the USA - it's just still at a small scale apparently. That's the answer to corn ethanol - use the stalks and leaves instead of the kernels.

  • by Stickerboy ( 61554 ) on Thursday March 29, 2007 @11:42PM (#18539149) Homepage
    Cellulosic ethanol [wikipedia.org] is a proven technology, the only issue now is ramping it up to industrial scale. Iogen [iogen.ca] and SunOpta [sunopta.com] (both Canadian biotech companies) have already built pilot plants, and are selecting sites to build industrial scale plants (In Iogen's case, they're contemplating offers from the US, Canada, and European countries to host the plant, which would produce 50 million+ gallons of ethanol a year.)

    The great thing about sugarcane and cellulosic ethanol production is they don't require outside power to run, unlike corn ethanol plants. They take a byproduct of the production process and use it for fuel.
  • by slapyslapslap ( 995769 ) on Thursday March 29, 2007 @11:54PM (#18539227)
    Look, corn isn't the most efficient method of producing ethanol by a long shot. But that it takes more energy to produce simply isn't true.

    This used to be true when talking about old inefficient ethanol plants. Today's corn ethanol production sees a net gain in energy. It's roughly a 1:1.3 ratio of BTUs in to BTUs out. These are well substantiated and accepted numbers. That paper put out by Berkley that everyone uses to spout that old myth wasn't accurate. It made a lot of assumptions to the low end of crop production, and efficiency, but high assumptions for fossil fuel based fertilizers and diesel farm equipment. It was set up to make corn ethanol look worse than it was, and quickly moved towards an anti agribusiness bias.

    I realize that 1:1.3 is barely more, but consider that the goal isn't so much to remove our dependence on fossil fuels, but foreign oil. Natual gas and coal are what fire the distilleries, not oil. So essentially, when using corn based ethanol, we are using coal, natual gas, and a little solar energy to fuel our vehicles. I'm OK with that for now. We have a lot of it. Eventually, other better crops will supplement and perhaps replace corn. The distilleries don't really have to do a lot of retrofitting and changing to take new sources of carbohydrate.
  • by Mr. Stinky ( 753712 ) on Friday March 30, 2007 @12:13AM (#18539365) Homepage
    BluefireEthanol [bluefireethanol.com] has the technology to viably convert cellulosic green waste into ethanol. Lots of green waste ends up at the dump already, these guys will convert it in a cost effective way. Ethanol is not just used as a fuel additive, it can also be used to make plastics and other materials. BlueFire's technology approach is unique because the inputs do not need to be sorted in advance like some biological processes which use specific enzymes for specific inputs. From their website:

    BlueFire Ethanol, Inc. is established to deploy the commercially ready, patented, and proven Arkenol Technology Process for the profitable conversion of cellulosic ("Green Waste") waste materials to ethanol, a viable alternative to gasoline. BlueFire's use of the Arkenol Process Technology positions it as the only cellulose-to-ethanol company worldwide with demonstrated production of ethanol from urban trash (post-sorted MSW), rice and wheat straws, wood waste and other agricultural residues.
    If there was already a plant in New Orleans (and it survived the hurricane) they could have made tons of ethanol from all of the waste debris that resulted from Katrina. Talk about making lemonade out of lemons!
  • by tylernt ( 581794 ) on Friday March 30, 2007 @12:18AM (#18539405)

    But ethanol is such a poor fuel compared to biodiesel I am amazed it gets the attention it does.

    There's no technical reason for it.
    Ah, but there *is* a technical reason. Crappy American passenger car diesels from the 70's gas crunch were unreliable, slow, noisy, and dirty. Americans have never really lost that image of small diesels, notwithstanding the slick and highly refined modern diesels made by VW and Mercedes today.

    We can only hope that the new ULSD (Ultra Low Sulfur Diesel) now required in the US will usher in a boom of popularity for diesel passenger cars now that emissions are less of an issue. The diesel Jeep Liberty is a step in the right direction -- we might even dream of someday buying an American passenger car with a diesel engine in it... I'm not holding my breath, though.
  • by NotQuiteReal ( 608241 ) on Friday March 30, 2007 @12:19AM (#18539423) Journal
    Seriously - there seems to be plenty of oil still. Maybe even more than was once thought. (Google "north pole oil" for details).

    The unstated point of the whole question of "alternative" fuels probably has something to do with "global warming" (which probably IS happening) and the underlying assumption that we human critters have a gnat's-ass of influence on said warming (which we do - have a gnat's-ass worth of input, i.e. not much.) Google "The Great Global Warming Swindle" for some interesting links.

    You can choose a "side", but think about it a bit first.

  • by MtViewGuy ( 197597 ) on Friday March 30, 2007 @02:16AM (#18540085)
    One company--GreenFuel Technologies--has already demonstrated how to use the exhaust gases from a coal-fired powerplant to "feed" tanks of oil-laden algae that could grow the algae at a tremendous rate.

    This system offers a number of obvious advantages:

    1. It reduces the pollutant output far below Kyoto Protocol mandates since the algae absorption of the exhaust gases cuts CO2 and NOx emissions way more than 50%.

    2. With a couple of hundred acres of tanks fed by the coal powerplant exhaust, we could produce millions of gallons of diesel/heating oil fuel per year from ONE site.

    3. The "waste" from the processing of the oil-laden algae could be processed into animal feed, plant fertilizer or even ethanol.
  • by SerpentMage ( 13390 ) on Friday March 30, 2007 @02:35AM (#18540157)
    Chavez is moving from elected to dictatorship! Look at the statements he has made when the constitution requires him to step down. He says he will not step down, but change the constitution. He also now has power to do whatever he wants. BTW one tell tale sign that he is a dictator is his every increasing majority! After all Saddam had something like 98% of the vote, but I doubt anybody would say he was democratically elected!

    Holding an election does not necessarily imply democracy... Democracy is the ability to vote and have freedoms without the interference of government. The interference part is definitely not happening with Chavez!
  • by jopet ( 538074 ) on Friday March 30, 2007 @06:41AM (#18541229) Journal
    There is no future that would allow everyone on this planet to drive around at will, fly around at will, eat strawberries flewn around the globe and tons of meat at will at the same cost and with equal or less ecological impact as/than now.

    This is simply not possible, mathematically. Either we want to utilize some renewable energy, then the sheer area of land needed to grow the apropriate crop would not be ecologically acceptable. Or we find a better and cheaper way to exploit still more fossile energy: that would further increase the amount of CO2 released to the atmosphere. Finally, even with some "magic" endless form of energy the future looks dim: if e.g. fusion or something similar would finally work then the cheap and endless supply of energy would make it possible to sustain an even larger number of people and give them the means to drive around at will, fly around at will, eat strawberries flewn around the globe and meat at will which would in turn indirectly lead to the exploitation and destruction of an even bigger part of the environment (all these people living in luxury need natural resources, produce waste, produce toxic substances, need their own houses, roads etc.)

    So, in order for people living on this planet without eating it up, destroying most of their fellow species, and totally covering it with artefacts and trash at some point, the only chance really is that energy gets more expensive and more precious. The only way to prevent utter destruction is that energy is costly and not available to everyone in huge quantities.

    As far as I can see, with a more long term vision of "future", nothing can be the future except precious, expensive energy.
  • Castro is right (Score:5, Interesting)

    by Simon Brooke ( 45012 ) * <stillyet@googlemail.com> on Friday March 30, 2007 @07:08AM (#18541321) Homepage Journal

    How to make yourself unpopular on a US based system...

    However, seriously, between 1845 and 1849 Ireland had successive years of record harvests, and in each year exported huge amounts of grain. What's famous about those years? Yes, that's the Great Famine [wikipedia.org]. People worked all day producing wheat which they couldn't afford to buy, so it was exported and they starved. There was no shortage of food in Ireland during the famine; there was a shortage of food ordinary Irish people could afford to buy. Similarly, in the Ethiopian famine of the mid 1980s which led to the formation of Live Aid [wikipedia.org], Ethiopia - so plagued with drought that it could not feed its people - was exporting so many water melons to Europe that it could afford to buy helicopter gunships with the proceeds. Again, people starved not because there was no food, but because they could not afford the food that was plentiful.

    The world's agricultural system is at full stretch at present producing enough food for (most of) the world's population. But our machines consume far more calories than we do ourselves. So if we switch our machines from consuming fossil fuels to consuming bio-fuels, then all the worlds agricultural land put together is not enough.

    One of the inevitable consequences of capitalism is that it distributes scarce goods inequitably. In a drought, the poor go thirsty while the rich water their golf courses. In a famine, the poor starve while the rich put biodiesel into their SUVs. This flies in the face of every system of ethics we know, and yet it is the inevitable consequence of capitalism. Ghandi said 'the earth produces enough for everyone's need, but not enough for everyone's greed'. Personally, I think he was an optimist; but nevertheless, one person's biodiesel is - inevitably - another person's hunger.

  • by indifferent children ( 842621 ) on Friday March 30, 2007 @08:37AM (#18541817)
    Too much of what is going on today can't be understood if your knowledge of world events pretty much ends at WW2

    My wife doesn't like sad movies. When we were watching Peter Jackson's King Kong, right about the point where the ape is spinning on the frozen pond in Central Park, and the army is setting-up, she asks, "Nothing bad happens to him, right?" I didn't know that she didn't know how King Kong ends. So that's where we stopped it. As far as she knows, King Kong ends with a happy beastie butt-skating in Central Park.

    If you do that same thing with U.S. History stopping at WWII, we look pretty decent.

  • by Anonymous Coward on Friday March 30, 2007 @09:57AM (#18542607)
    Ethanol, burned to produce an equal amount of energy to a specific amount of octane is going to produce an equal amount of carbon dioxide. The whole motivation to use ethanol as fuel is completely misguided. (Or a not so clever ploy.)

    Heats of combustion of Ethanol vs n-Octane from my 1989 CRC Handbook (in kilogram calories per gram molecular weight):
    Ethanol: 326.68 (~327 kcal/mol ~= 1367 kJ/mol)
    n-Octane: 1302.7 (~1303 kcal/mol ~= 5450 kJ/mol)

    Complete combustion reactions:
    Ethanol: C2H5OH + 3 O2 = 2 CO2 + 3 H2O (-1367 kJ/mol)
    Octane: 2 C8H18 + 25 O2 = 18 H2O + 16 CO2 (-5450 kJ/mol) ...equalised by mols of CO2:
    Ethanol: 8 C2H5OH + 24 O2 = 24 H2O + 16 CO2 (-10.9 MJ)
    Octane: 2 C8H18 + 25 O2 = 18 H2O + 16 CO2 (-10.9 MJ)

    So, you can see that to produce equal amounts of energy by combustion of either fuel, one must produce equal amounts of carbon dioxide.

    In fact, ethanol from corn will produce more carbon dioxide overall, as the carbon dioxide produced by fermentation of corn to produce ethanol will more than offset the benefits of its relatively clean combustion.

    Burning ethanol does nothing to reduce greenhouse gas emissions. It is a convenient way for the petrochemical industry to prolong its inevitable death. A number of petro stations in Canada have been selling gasoline with up to 15% by volume ethanol for decades now (Sunoco in particular).

    Granted, gasoline is of course not pure n-Octane, and contains lots of other crap. Its mostly the toluenes and related aromatics that give gasoline its smell, pure octanes have very little aroma, slightly minty if anything.

    Combustion of gasoline is less likely to be complete, so burning ethanol is going to be cleaner in terms of emissions and will produce fewer toxic byproducts of combustion, but will do NOTHING WHATSOEVER to help global warming. I find it amusing how easily the public and businesses are fooled.

    Now, what does make some sense to me is to produce biodiesel from rapeseed (canola) or hempseed (marijuana), in terms of ease of production and sustainability, but again, burning these fuels for energy is not going to help global warming, the same amount of CO2 will be produced.

    The answer obviously is CANDU nuclear reactors and electric/flywheel vehicles, but this would destroy the profits of many powerful corporations, and so will not happen under democratic capitalism. The market indices must never decrease, regardless of the cost, even if that cost is the future of humanity. We are on a path to self destruction and violent revolution is the only way out, but I fear that will never happen.

    The price of corn has nothing to do with it, feeding the poor has nothing to do with it, its all about protecting the financial interests of those in control. The future of man be damned.

    Sleep well.
  • by Anonymous Coward on Friday March 30, 2007 @10:16AM (#18542845)
    There are farmers that would rather plow under their healthy crops than sell it unprofitably.
    There are farmers that would rather grow illegal crops for drug production than sell current unprofitable food researves to be given to countries (that make NO efforts on population control or social resposibility).
    Farmers in starving countries are going bankrupt from the free food given to the country so future food supply in that country is greatly harmed.
    More free food to starving countries that have no population control simply equals more starving babies and children... a never ending story of starvation and poverty for both farmers and poverty stricken countries.

    BioFuels helps the War against Drugs and fighting poverty world-wide.
  • by 0100010001010011 ( 652467 ) on Friday March 30, 2007 @10:18AM (#18542869)
    Since this is slashdot and everyone wants reasonable numbers, here we go.

    First off. Gear ratios are normally specified as 2.3, 2.4. These are meaning 2.3:1. 2.3 revolutions of the engine per revolution of the tire. 1:10000 is backwards.

    Find: Gear ratios required to move 200 car train to 100 mph.

    Assumptions:
    Gear ratio specified is final engine:wheels gear ratio. I'm not going to deal with separate gear rations, final drives and rear end ratios.
    Train wheels are 18" in diameter.
    Trains are pulling the same freight that goes over the road in those big boxes that move in between.
    Gear ratios from a truck 'scale' well to large size. Meaning if 1 semi needs X:1 ratio to move 1 car. Y*X:1 ratio is needed to move Y cars. This is just to get the same amount of torque multiplication.
    50% overlap in powerbands. On manual transmissions redline in 1st gear doesn't match up to idle in 2nd. There is a bit of overlap, allowing you to drive for speed, pulling, economy, etc.
    Our manual transmission on highway truck for pulling 1 'car' will be a Cat C13 [cat.com]. With 1550 ft-lbs. Our manual transmission locomotive will be running a Caterpillar C3516C [cat.com]
    Since I can't find a torque curve for the 3516. We will use HP=Torque (ft-lb)*RPM/5252.
    Diesel torque curves are flat for their operating range, 1000-1800 RPM.
    Eaton 13 speed manual transmission, first gear 19.7:1. Eaton rear end ration of 2:1.
    Calculations:
    HP ~= 500 @ 1000 RPM. Therefore torque is around 2626 ft-lbs for the C3517.

    Torque required to get 1 car moving is 19.7*2*1550 ft-lbs=61070 ft-lbs
    Torque required to get 200 cars moving is 200*61070 ft-lbs=1.2E7 ft-lbs
    If the engine puts on 2626 ft-lbs, the first gear ratio will need to be: 200*61070/2626= 4651:1.


    18" wheels * Pi = 56.5 in / rotation.
    Speed in First gear at 1400 RPM = Speed in Second Gear at 1000 RPM.
    etc
    This will allow the 50% overlap for operating in torque bands.


    So you're in 1st gear. You're turning 1000 RPM (you finally got your massive clutch pack to sync up). You are going a blistering:
    56.5 in / rotation * 1000 rotations / minute * 1/4651.1 * 1 foot / (12 inches) * 1 mile / (5280 feet) * (60 minutes) / (1 hour)=0.012 MPH


    By time you're upto 1400 RPM you're now cranking out 0.016 MPH.


    So you need to find your 2nd gear ratio
    56.5 in / rotation * 1000 rotations / minute * 1/X* 1 foot / (12 inches) * 1 mile / (5280 feet) * (60 minutes) / (1 hour)=0.016 MPH.
    Solve for X.
    Second gear ratio is 3320:1.
    Etc. I set up a spreadsheet to calculate all the gears (With much help from my TI-89 to get numbers). I published it through google docs here: "Manual Transmission Locomotive" [google.com].

    So you were correct, my hyberbole numbers were completely off. However I think it illustrated the point. A gear ratio of 4600:1 means one gear is going to have 4600 teeth for every tooth another gear has. In addition you're going to need 28 gears to cruise at 1000 RPM and 100 MPH. Not to mention the size of shafts and gear sizes needed to transmit 1.2E7 ft-lbs. On-highway trucks already have multiple clutch packs to get that amount of torque in a small overall diameter. (If you're patient, I could find my machine design books and I could calculate the number of clutch packs given an overall radius 1 ft/clutch. Heck I could run the numbers required to get the gear sizes to transmit the torques)

    Plus you bring up tons of feasability issues. Braking would be quite difficult. Most locomotives use EMF braking. They turn all their electric motors into generators and dump all that energy to a grid. I suppose you could install a compression brake and make the engineer downshift thr
  • by sjwaste ( 780063 ) on Friday March 30, 2007 @10:37AM (#18543183)
    As the owner of a Supra, I'm aware of some pretty redneck projects like sticking a 350 under the hood, but nothing to the effect of what you're describing. I'd really like to see it done, though, I think it might be a good idea and the car's a good candidate for it.

    I would suggest staying with the stock engine to start, though. In the 3rd gen, you're getting 250 ft-lbs of torque stock out of a 3L I6, and quite a bit more with basic modifications. It'd be a lot easier to keep that than trying to shoehorn in a diesel, at least to start. You could drop out the transmission and try the alternator idea, there's a lot of room under there. But I think the suspension would make the hub motors a difficult idea. Not impossible since there's a lot of space in there, but you'd essentially need to fab new hubs that can fit a motor and still mount to the upper/lower A-arms.

    Assuming the stock engine, would replacing the driveline with motors at the hubs be a net gain over normal driveline losses? I'm nearly certain you'd come out ahead with a diesel engine.
  • by Epi-man ( 59145 ) on Friday March 30, 2007 @11:48AM (#18544149) Journal

    In related news, Fidel Castro is blasting the production of corn fuel as a blatant waste of food that would otherwise feed 3 billion people who will die of hunger.


    I am sorry for being so cold and callous as I enjoy my luxurious life in the US, but why do we fight so hard to have more people living in areas where they apparently shouldn't be living per Mother Nature? I get so frustrated when people talk about the food supply problems and the water supply problems and how are we going to solve all these problems when perhaps, maybe, just maybe it is time to consider that the planet has enough human beings on it and adding to the population isn't the best move? Reminds me of the Matrix and Agent Smith's analysis of the human species as the only one that doesn't live within its bounds.

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