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Biotech Power Science

Mutant Algae to Fuel Cars of Tomorrow? 158

Hugh Pickens writes "Algae has long been known as a promising source of biodiesel. It's worth noting, though, that algae also produces a small amount of hydrogen during photosynthesis. The MIT Technology Review reports that researchers have created a mutant algae that makes better use of sunlight to increase the amount of hydrogen that the algae produce. Anastasios Melis and his team at the University of California have manipulated the genes that control the amount of chlorophyll in the algae's chloroplasts. Although the process is still at least five years from being used for hydrogen generation, Melis estimates that if 50% of the algae's photosynthesis could be directed toward hydrogen production, an acre could produce 40 kilograms of hydrogen per day. At the price of $2.80 a kilogram, hydrogen could compete with gasoline, since a kilogram of hydrogen is equivalent in energy to a gallon of gasoline."
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Mutant Algae to Fuel Cars of Tomorrow?

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  • Re:Feasible (Score:5, Insightful)

    by jcr ( 53032 ) <jcr.mac@com> on Saturday September 29, 2007 @05:45AM (#20792289) Journal
    Ethanol is a corporate welfare scam. The government knows it, ADM and Gargil know it, the DOE knows it, and the politicians are hoping that you and I don't. Generating fuel from algae or bacteria would be so much better on so many levels than fermenting corn, I really hope it comes to fruition.

    Just imagine the effect on world politics if nobody cared who had control of the petroleum in the middle east, because it was selling for $4/bbl.

  • Re:Feasible (Score:2, Insightful)

    by thanatos_x ( 1086171 ) on Saturday September 29, 2007 @05:47AM (#20792295)
    It's not a matter of how much farmland we have, it's oceans (or lakes, if it's a freshwater variety). If this works, it'd be a great boon to the environment - The algae removes C02 from the air, and creates H2, which unlike ethanol or other green fuels releases no CO2 back into the environment.

    Granted, there's an issue of oxygen removal from the water and disrupting the balance of an already stressed environment, but if it was done in largely dead ocean areas, this shouldn't be too much of a problem.

    Now if we can only find a fast breeding (but non-disruptive), good tasting fish who likes to eat algae... we'd solve 3 key problems - ocean depletion, CO2 emissions, and an energy source.
  • by physicsphairy ( 720718 ) on Saturday September 29, 2007 @06:06AM (#20792335) Homepage

    If "a kilogram of hydrogen is equivalent in energy to a gallon of gasoline" then, estimating [] about 400 million gallons of gas per day used by the US, we will need 10 million acres of algae farm. That is with the assumption that they obtain their optimal output, and no additional energy is expended for processing, transport, etc.

    By contrast, an average nuclear power plant produces 1000 megawatts of energy. Also assuming optimum efficiency, we get (10^9 joules pers second * (60 * 60 *24) seconds per day / (237.1*10^3 joules to electrolyze 1 mole of hydrogen at 298K) * 1.01 grams/mole = 368,047 kilograms of hydrogen per day.

    So... 10 nuclear plants, or 10 million acres of algae farm?

    Let's not forget that your algae farm will stop photosynthesizing when it's cloudy out.

  • by onyxruby ( 118189 ) <onyxruby&comcast,net> on Saturday September 29, 2007 @06:08AM (#20792343)
    Wikipedia is attempting to index what, the Internet? Wikipedia cites only popular persistant opinions of very narrow political persuasions. Pick a contorversial topic, it doesn't matter what it is, said writing is full of bias presented as fact often bordering or outright propoganda. I have a problem when people assume that popular persistent opinions somehow equal truth, accuracy or science. I'm not the one who cited something. Besides, since when has it ever been prudent to ask readers of a story to provide their own cites? I have done technical writing in one form or another for a decade now, providing a reliable cite is par for the course. Your not one of those that thinks people have a duty to update wikipedia are you?
  • by Zouden ( 232738 ) on Saturday September 29, 2007 @06:13AM (#20792349)

    Get a few of these mutants made, let em breed, and harness the work.

    A major reason why this won't ever be as economical as biodiesel production is that this requires mutant algae, as you said. This means the culture needs to be kept isolated from the outside world to keep it pure (the mutants have reduced fitness compared to wildtype algae).
    Biodiesel, on the other hand, is produced by wildtype algae that are capable of holding their own against competing organisms.
    If I had more time, I'd dig up photos of the respective bioreactor design. Hydrogen production requires sealed, sterile, glass containers, while biodiesel production simply requires an irrigated ditch.
  • Re:Feasible (Score:5, Insightful)

    by SatanicPuppy ( 611928 ) * <.Satanicpuppy. .at.> on Saturday September 29, 2007 @06:29AM (#20792383) Journal
    It produces nearly enough hydrogen per acre to make "backyard" hydrogen farms feasible.

    Instead of thinking entirely in terms of big honking swaths of farmland covered in algae, think of 5 or 6 vertical tanks in every backyard, producing ~4kg of hydrogen a day. That would cover automotive energy needs for the average person, probably with some left over.

    Also, while farming this stuff right in the ocean wouldn't make much sense, floating farms would be practical, and a good use of space.

    I'm a big fan of the idea of using the kind of space that we already waste for energy production (e.g the tops of every wal-mart in america covered in solar cells). Even a land efficient method like this one could benefit from using parts of land that we already use for another, non-conflicting, purpose.
  • Re:Feasible (Score:3, Insightful)

    by chuckymonkey ( 1059244 ) <.charles.d.burton. .at.> on Saturday September 29, 2007 @06:32AM (#20792393) Journal
    I like the way you think. Putting them in the backyard definately would solve most of the storage problem, and if I'm not mistaken (not sure about this breed) couldn't you feed the algae your housewaste including graywater?
  • by RsG ( 809189 ) on Saturday September 29, 2007 @06:37AM (#20792397)
    Why do people keep saying this? It's like they don't actually understand why fossil fuels contribute to the greenhouse effect.

    Look, carbon that's locked away underground in the form of fossil fuels isn't part of the carbon cycle. It's been sequestered by geological processes for millions of years, removing it from the air. When we dig it up and burn it, we bring it back into circulation. The total amount of airborne carbon increases; the greenhouse effect gets stronger. This is, in a nutshell, anthropic global warming.

    Carbon that's already in the atmosphere can be trapped by photosynthesis. If the plant that trapped the carbon is then burned, or eaten, or even if it just dies and rots, the carbon returns to the air. This is the regular carbon cycle, with or without human intervention, and it doesn't alter the net balance of Co2. It's this process that we employ when we make biodiesel.

    Biodiesel doesn't contribute to global warming. At all. The "bio" part means the hydrocarbons were synthesized from plant matter; the carbon in those hydrocarbons came from airborne Co2. As long as you plant biofuel crops, process them, and burn them, the total amount of airborne Co2 will never increase. Every ounce of carbon added to the air is matched by an ounce of carbon removed from the air by the fuel plantation.
  • by Morgaine ( 4316 ) on Saturday September 29, 2007 @09:30AM (#20792863)
    > Wikipedia, the concept that persistent opinions are accurate opinions

    Persistent opinions ARE accurate opinions in many fields (to the best of human knowledge), and in other fields they're not.

    The only strong "limitation" of Wikipedia's model is that it requires readers to understand which field falls into which category. If you wish to accuse Wikipedia of not being 100% useful to totally non-perceptive readers, then yes you're right, one would have to agree with you. It's only useful to totally non-perceptive readers when they happen to be reading pages of the first kind, not the second. But those who are perceptive know how much to trust both kinds of article.

    The types of fields in which persistent opinions are accurate opinions are those ruled by verifiable fact, the rule of mathematics and logic, and cooperative progress through explicit reasoning, not through debate. That includes mathematics and logic themselves, plus all the hard sciences and branches of engineering. It excludes almost everything else, even many fields that try to employ logical discourse (eg. about 95% of philosophy is excluded). And even harsher than this, it also excludes personal opinion within the included fields: for example, it excludes personal interpretations in climatology and claimed predictions for the future, while including the very scientific fact finding and analysis in that field of science.

    To those who understand the above, Wikipedia is an invaluable resource, because (apart from occasional human error and abuse, which are both rapidly corrected) the entries are all made cooperatively and all new progress builds upon past progress. Thus, the entries that persist represent the current peak of human understanding.

    This contrasts markedly with the other kind of fields, in which personal opinion, claimed experience, authoritative position, and vocal statements matter. Yes, you can't trust anything that you read in those fields on Wikipedia, but that's not Wikipedia's problem. You can't trust what you read about those field on any other forum or means of communication either.

    So, if you have a problem with trusting Wikipedia, it's either because you work in fields of the second kind (and hence you're part of the problem), or else because you fail to understand how human endeavour is split into those two very different categories and so you don't apply suitably varying degrees of trust.

    It's your problem, not ours on the science and engineering side. Wikipedia serves us well.
  • by Flying pig ( 925874 ) on Saturday September 29, 2007 @09:43AM (#20792937)
    This is absolutely true provided that oil is not needed to fuel the processing. Currently, for instance, ethanol production in the US requires a very significant input of oil. Therefore, while demand for energy is increasing, satisfying some of that demand with ethanol will only at best reduce the slope of the release curve.

    This ceases to be true when biofuels become totally self sufficient. This means that fertiliser plants, the plants that manufacture everything used in the biofuel production cycle, storage etc., are all being entirely fuelled by their own product.

    For this reason, for many years to come, biodiesel has to be the preferred route. This is because the huge installed base of plant can mostly run on it; you can do process heating with biodiesel as well as run generators, trucks and ships. You can, as it were, bootstrap the biodiesel economy, whereas you cannot bootstrap the ethanol or hydrogen economies. Steel plants and machine shops cannot run on either.

    Hydrogen is attractive to the vehicle industry not because it is efficient but because it requires replacement of the entire vehicle fleet and would provide a boost to the industry. Biodiesel allows the existing fleet to be replaced much more slowly, with the same emissions benefits.

    One of the simplest ways to reduce anthropogenic global warming is just to use less energy. One of the best ways to do that is to make consumer durables last longer, and make them out of readily recyclable materials. But that threatens the entire basis of the US-Chinese industrial complex, whereas hydrogen offers it greatly increased opportunities to expand.

  • by Flying pig ( 925874 ) on Saturday September 29, 2007 @10:41AM (#20793319)
    The downside of the horse is that it is unsuited to high density urban environments. Not without reason is the horseman a symbol of the aristocracy. If New York or London had the same horse population as they currently have cars, nothing would move because of the height of the horse dung (and no technical solution to removing it without powered transport.) Even in 18th century England, there was a profitable occupation in large cities of "crossing-sweeper", i.e. somebody who cleaned the dung off a section across roads and charged pedestrians for the right to cross.

    That's without considering that the entire planet would be given over to growing grass. Unlike cars, horses consume a lot of fuel even when going nowhere. You have to be quite well off to be an Amish.

  • Re:transition (Score:5, Insightful)

    by budgenator ( 254554 ) on Saturday September 29, 2007 @01:35PM (#20794535) Journal
    I live in sugar beet country and I can assure you that we didn't forget, I'm also in corn country so that gets a lot of noise as well. The real answer will be more like
    1. grow the corn,
    2. grow the beets,
    3. press out the oils out of the corn for food use,
    4. reclaim the used food stuff oils aned animal fats for biodiesel,
    5 extract the sugars from the corn, feed the distiller's dried grain and roughage back to the cows (makes food and animal fat for step 4)
    6. add beet sugar to the corn sugar and make Butanol [] instead of inefficient Ethanol
    7. profit!

    I don't think there will ever be a one answer answer; the answer will be multi-use feed the waste of one almost economical process to the next almost economical process.

"Even if you're on the right track, you'll get run over if you just sit there." -- Will Rogers