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Transportation Science

Scientists Create New Gasoline Substitute Out of Plants 419

destinyland writes "California scientists have just created a new biofuel using plants that burns just as well as a petroleum-based fuel. 'The discovery, published in the journal Nature, means corn, sugar cane, grasses and other fast-growing plants or trees, like eucalyptus, could be used to make the propellant, replacing oil,' writes the San Francisco Chronicle, and the researchers predict mass marketing of their product within 5 to 10 years. They created their fuel using a fermentation process that was first discovered in 1914, but which was then discontinued in 1965 when petroleum became the dominant source of fuel. The new fuel actually contains more energy per gallon than is currently contained in ethanol, and its potency can even be adjusted for summer or winter driving."
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Scientists Create New Gasoline Substitute Out of Plants

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  • Re:hmm (Score:4, Informative)

    by ComfortablyAmbiguous ( 1740854 ) on Thursday January 17, 2013 @01:36AM (#42613667)
    Well, if you wanted to really keep your energy usage down you'd grow a nitrogen fixing plant like peanuts every other year, avoiding the need for petroleum based fertilizers.
  • by Animats ( 122034 ) on Thursday January 17, 2013 @02:03AM (#42613879) Homepage

    Until cost and EROEI [wikipedia.org] figures come out, this is vaporware. There are lots of ways to make fuel from biomass, but most of them are too expensive. Some consume more energy than they produce (EROEI < 1). Any useful process needs an EROEI over 5, and preferably over 10, to be worth the trouble. Photovoltaic is now up to 7, which is encouraging. Ethanol from corn is listed as 1.3, and some studies put it at less than 1. (Ethanol distillation plants, unlike oil refineries, don't run on their own product; they take in natural gas or some other fuel.)

    I see the hemp enthusiasts are out in force again. Hemp isn't a good fuel crop. If you just want biomass for cellulose, you use agricultural waste - corn husks and cobs, straw, bagasse from sugar cane, etc. Hemp seed oil is useful, but only a small part of the biomass comes out as oil. There are better plants for direct oil production.

  • by afgam28 ( 48611 ) on Thursday January 17, 2013 @03:19AM (#42614221)

    According to this site [cnn.com] total global food production is 4.4 billion tonnes per year, so in a world of 7 billion people that's 629 kg per person per year, or 1.7 kg per day. The average (median) American eats 1.03 kg per day, and the 90th percentile eats 1.73 kg per day, according to the EPA [epa.gov].

    About 2.4 billion tonnes is cereals [wikipedia.org] (e.g. corn, rice, wheat).

    So yeah, if we're producing enough to feed 7 billion 90th percentile Americans, I think it's safe to say it's a distribution problem not a supply problem.

  • by Anonymous Coward on Thursday January 17, 2013 @03:48AM (#42614327)

    Eh, actually, no. Growing Hemp is pretty much forbidden in all of Europe, except for Switzerland where they allow certain kinds of low-THC strains to be grown. However, this is strictly regulated.

  • by rve ( 4436 ) on Thursday January 17, 2013 @04:25AM (#42614451)

    That sounds like a load of bullshit to me. ....
    - How was the total US energy 'budget' calculated? Note the word 'budget' not 'usage' .. which is indicative of an estimate, not a fact

    Up to the industrial revolution, our main source of fuel used to be biomass: wood (charcoal). Keep in mind that this was when the population size and total energy use of western civilization were tiny by today's standards. Nevertheless, we managed to run out of wood.

    Britain and Ireland were almost completely stripped of trees. Even today, the only trees you'll find older than the industrial revolution are in places that were some noble family's private hunting ground at the time. The eastern mediterranean was stripped of trees as far back as ancient times, and still hasn't recovered. In the low countries, after they ran out of wood, they started burning the soil (peat), turning their land into lakes, which they later had to drain to turn it back into land, which is why they now live below sea level. They did however make a fortune importing timber from the sparsely populated Baltic. Yes, wood had to come from as far as Russia and Finland, because western Europe had run out.

    Believe it or not, burning biofuels was an environmental disaster, and switching to coal allowed forests and wildlife to recover.

    Now, turning agricultural waste into fuel sounds like a good idea to me (that's what they do in Brazil with the leftovers from the sugar production), but when you're thinking of growing crops with the express purpose of making fuel, you have to consider the fact that modern, high-yield agriculture is effectively our way of using land to turn fossil fuel and sunlight into food. Tilling, sowing, fertilizing, pest control, harvesting, processing and transport together have to use substantially less energy than the fuel you are making will yield.

    Clearly, land + fuel + sunlight -> food -> fuel -> energy is an inefficient process. Why not eliminate a couple of conversion steps from the process, and use solar cells to generate electricity? The process land + sunlight -> energy has fewer inefficient conversion steps.

  • Re:hmm (Score:3, Informative)

    by Anonymous Coward on Thursday January 17, 2013 @04:43AM (#42614497)

    or invent god-like batteries

    We have, it's called pumped hydro storage. It requires construction - just like a coal or nuclear plant - but once operating and fed by sources such as wind and solar it provides a very low pollution on-demand power supply.

  • Re:hmm (Score:5, Informative)

    by Kokuyo ( 549451 ) on Thursday January 17, 2013 @04:50AM (#42614523) Journal

    I think that's exactly what the parent poster said: Without storage capabilities or the means to redistribute the energy across the world from anywhere to anywhere at any time, base load is still the most important factor. And in this, I absolutely agree.

    Not that we shouldn't use wind and solar, mind you. We should just stop fantasizing about it replacing nuclear anytime soon.

  • Re:hmm (Score:5, Informative)

    by Dodgy G33za ( 1669772 ) on Thursday January 17, 2013 @05:09AM (#42614581)

    We should just stop fantasizing about it replacing nuclear anytime soon.

    That is more about politics than it is about capability. You don't even need storage if you are prepared to oversupply enough. 180% covers 90% of the time, and a 270% oversupply will give you 99.9%. Figures based on the US continent I believe, so does not assume a world grid. The later oversupply figure is expected to be cost effective by 2030 as green tech becomes more cost efficient.

    A breakthrough in energy storage technology in the next 17 years would short circuit that time frame.

    In other words we can start the process of phasing out dirty energy right now.

    Source: http://www.greentechmedia.com/articles/read/how-about-99.9-percent-renewables [greentechmedia.com].

  • Re:hmm (Score:4, Informative)

    by whydavid ( 2593831 ) on Thursday January 17, 2013 @09:54AM (#42615797)
    "For comparison, the US consumes 1.39 x10^9 [eia.gov] litres of fuel per day. According to Wikipedia, the energy density of petrol is 49.2 x 10^6 J/L [wikipedia.org], so that's 684 x10^12 J of energy per day... or, expressed in Watt-days (86400 seconds in a day), that's 7.91 x10^9 W-days of energy." Wikipedia actually lists 34.2 MJ/L as the energy density of petrol. Since this supports your case, I'll use it. 1.39 x 10^9 L/day * 34.2 x 10^6 J/L = 47.538 x 10^15 J/day. I'm not sure what you did when you calculated daily energy use, but you were off by a couple orders of magnitude. Converting to watt-days (47.538 x 10^15 / 8.64 * 10^4) gives us 5.502 x 10^11 Watt-days. If we then divide this by 7.68 x 10^12 (20 percent of 6 percent of total sunlight energy falling on arable land, in accordance with your figures), we get about 7.2% of all land needed to meet energy needs, which is a far cry from 1% of all land providing 10 times more energy than we need. Of course, this is all still a fantasy. Fields need fertilizer or to be planted with crops that will naturally replenish the nitrogen in the soil. If the land isn't 'rested' periodically, yields will drop dramatically. Even with proper farming techniques, yields still will not be close to 100% of the maximum possible biomass. All of this assumes that there is plenty of water to go around; since the majority of US farmland suffered from drought in 2012 (http://www.ers.usda.gov/topics/in-the-news/us-drought-2012-farm-and-food-impacts.aspx), and we have known for a long time that aquifer levels are dropping dangerously low, I'm going to suggest that adequate water is not a safe assumption. Another consideration is that 7.2% (hopelessly optimistic as it is) refers to the total surface area of ground covered by crops. Even if we planted the crops such that they covered 100% of the planted area at maturity, we still have to consider the full life cycle of the plant from seed to maturity. So, that 6% figure may be correct, but the denominator is much smaller than the field on which the crops are planted. Also, 4 million square kilometers is way higher than the actual amount of arable land in the United States. You were looking at agricultural land (includes all farmland, including that which is suitable for livestock but not crops). Using your same source, arable land is actually 1,617,800 square km. This adjustment alone would push the 7.2% above to 17.8%, and that is without considering the other factors I listed. Finally, you have only considered gasoline, when it would be appropriate to include ultra-low sulfur diesel, which is used primarily for transportation. According to (http://www.api.org/~/media/Files/Oil-and-Natural-Gas/Gasoline/US_gasoline-distillate-update.pdf), ULSD production from 2007-2011 is 3.5 million barrels per day. Since the US exports a lot of diesel, and I don't know what percentage of that is actually used in the United States, I'll just split it down the middle and say that half is exported. This translates to 1.038 X 10^16 J/day or 1.201 x 10^11 additional Watt-days. If we count other types of diesel fuel (I don't know other types of diesel fuel are used for, so I just played it safe and assumed they could be replaced by grid power) and assume less than 50% is exported, this number could easily double and would more than triple if we used more recent data and assumed zero exports. I could keep going, but I think this is sufficient to show that your calculations were off by at least a few orders of magnitude.
  • by yurtinus ( 1590157 ) on Thursday January 17, 2013 @01:14PM (#42617865)
    Alaska doesn't own the oil production facilities, it just receives money from land leases and royalties on the oil fields as well as property taxes on the pipeline and other structures. So you can't specifically call it "communist" since the state doesn't own the means of production. Still doesn't change the fact that it isn't exactly the pillar of neo-conservatism what with the redistribution of wealth through the Permanent Fund.

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