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Power Science

Newest Energy Source — Pond Scum 289

Posted by ScuttleMonkey
from the slippery-when-wet dept.
An anonymous reader writes to tell us that several start up companies include one from MIT are looking at using (both natural and engineered) algae as source of bio-fuel. Since algae grows quickly and absorbs green house gases. From the article "Soybeans can give you 50 to 60 gallons of oil an acre compared to 75 to 125 gallons for canola, but algae is almost limitless because it grows so fast, so potentially you could get 10,000 gallons per acre."
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Newest Energy Source — Pond Scum

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  • by Anonymous Coward on Wednesday December 27, 2006 @06:31PM (#17381972)
    Oh wait, they are worse than pond scum.

  • Look to salt water (Score:2, Insightful)

    by P3NIS_CLEAVER (860022) on Wednesday December 27, 2006 @06:32PM (#17381976) Journal
    They should look into making retaining ponds and doing this in the ocean. Not only is freshwater in short supply most of the earths surface is salt water.
  • by Nom du Keyboard (633989) on Wednesday December 27, 2006 @06:45PM (#17382106)
    potentially you could get 10,000 gallons per acre.

    We are having a failure to think fourth dimensionally here. Time, folks, time! 10K gal. how often?. Yes it might be in the TFA, but that's no reason to omit it from the summary.

  • by Rosco P. Coltrane (209368) on Wednesday December 27, 2006 @06:56PM (#17382202)
    If that was in 1998, then at should be very feasible with current petrol costs, especially taking into account the added value of removing CO2 from the atmosphere.

    The problem is, taking into account inflation, in constant dollars, oil costs less today than it did 30 years ago. Yes, even at $4/gallon. So the project is still not worth doing.

    As for the added value of removing CO2 from the atmosphere, I don't think this country cares much about pollution, unless it affects people's way of life, which is doesn't (so far). A noble pursuit to be sure, but one Americans don't give a fuck about.
  • by aarku (151823) on Wednesday December 27, 2006 @07:02PM (#17382260) Journal
    I found this conclusion interesting: "...we project costs for biodiesel which are two times higher than current petroleum diesel fuel costs." (Emphasis mine)

    So the price of gasoline in 1998, the year the paper was written, was around $1.25 per gallon. I'll pay $2.50 a gallon for algae fuel anyday.
  • by Anonymous Coward on Wednesday December 27, 2006 @07:20PM (#17382414)
    You're neglecting improvements in technology for both processes. I suspect it's easier to go from algae to biodiesel, than it is from oil to gasoline. Plus it's harder to get oil from it's source than it is getting algae from it's source.* I've seen plans over a decade ago about putting transparent tubes coiled across the desert, and pumping algae through that, then filering at the plant.

    *Note that includes the efforts to find the oil. Plus biodiesel could be made close to the source, while oil refineries are a good distance away.
  • by ibn_khaldun (814417) on Wednesday December 27, 2006 @07:24PM (#17382450)
    TFA seems remarkably unconcerned about the fact that dense concentrations of algae require a continuous supply of water, which is not required for soybeans, canola, etc. Add to this the proposal that these algae farms are going to be in the desert -- an environment not noted for concentrations of water -- and one wonders how all of this is going to work on a large scale. Perhaps we could scumify [technical term...] a few of the more notorious human-engineered desert lakes -- Mead, Powell, Nasser, Chad, and there are probably others -- but one isn't going to immediately make Death Valley or the Gobi into the Saudi Arabia of scum-fed biofuels.
  • by sphealey (2855) on Wednesday December 27, 2006 @07:28PM (#17382490)
    I have been reading about biodiesel from algae for at least 5 years now. Sounds great: Closed carbon cycle. Free energy from sunlight. Happy friendly energy.

    My question is: where are the big oil companies? Why aren't they buying up huge tracts of land in southern Texas and Mexico and digging huge ponds? Why aren't the hiring algae biologists by the thousands? Building proof test algae refineries? Seems to me that if this were such a great idea ExxonMobil etc would be all over it like flies on algae (so to speak).

    Perhaps they are and it is all being kept secret. But as far as I can tell every article/web post/discussion of this process traces back to a single paper by a single biology professor with some basic input/output calculations and not much else. Which makes me a bit suspicious.

  • by Thomas the Doubter (1016806) on Wednesday December 27, 2006 @07:33PM (#17382526)
    The problem with algae as a biodiesel source is that algae have a very low oil content. The oil from soybeans and cannola is extracted almost directly, while any substantial percentage of the fuel value of algae in the form of oil would have to be synthesized at high cost. To simply extract oil from algae we would have to re-engineer algae to produce more oils, and even then, the gross biomass to oil ratio would likely be quite high.
  • by nacturation (646836) <nacturation&gmail,com> on Wednesday December 27, 2006 @07:36PM (#17382550) Journal

    And, of course, there is still another factor: solar cells produce electricity that can be used immediately, algae need some sort of processing to generate useful energy.
    On the flip side, also consider that solar cells produce electricity that must be used immediately, while the algae -> oil process results in stored energy that can be used later.
  • by Bananatree3 (872975) on Wednesday December 27, 2006 @07:39PM (#17382578)
    What makes biodiesel renewable is the fact that you are recycling a net amount of carbon. Over the growth period of a biodiesel harvest (in this case algae), the plants would have absorbed about the same amount of CO2 that had been generated by the burning of the previous harvest. I.E: The amount of CO2 put into the atmosphere from burning biodiesel made from last years harvest would be recaptured by this years harvest, assuming the current harvest is of similar or larger size.

    Burning fossil fuels creates a similar cycle in which CO2 in the atmosphere is absorbed by plants which then over an extordinarily long period of time turn into oil/coal. However, this process of plants turning into the black stuff takes millions of years, much much slower than the rate at which it is currently being burned. On the other hand, harvesting plants to convert to biodiesel takes only a handful of months (with crops/algae). The speed at which the plant matter is generated and the speed at which it is burned is much closer to each other, canceling each other out.

  • *yawn* (Score:4, Insightful)

    by Dolohov (114209) on Wednesday December 27, 2006 @07:45PM (#17382620)
    I'm getting tired of all the "*gasp* New Source of BioFuel!" articles I keep seeing. Look, all sorts of life creates all sorts of things that burn. Some significant portions of our body chemistry are designed to oxidize. This isn't rocket sci -- er, brain surgery here.

    The real problems aren't a matter of finding something else we can burn, it's a matter of creating a supply chain and infrastructure to rival that of petroleum in terms of quantity, price, availability and reliability, and then of maintaining that long enough for our dumb-ass auto companies to produce decent vehicles which make use of the new fuel, in the styles and manner that will persuade consumers to buy and drive them. In other words, the real problem isn't scientific, it's a matter of economics, logistics, and public policy.

    Wake me when someone solves *that* one.
  • by misleb (129952) on Wednesday December 27, 2006 @08:46PM (#17383060)
    Stories like this are why I don't worry about running out of oil or about global warming. Anytime the system begins to get unbalanced it forces a correction through the free market, and it works even faster and better when the government stays the hell out of things and allows nature to take its course.

    Ok, so lets say we don't run out of oil. Not only do we not run out of oil but it remains the most economically viable source of energy for some time to come. At what point does the "free market" then solve global warming? Seems to me that an unregulated free market would just keep on polluting until it is too late (or at least really bad).

    The only way to keep corporations from destroying the environment is to regulate them. Enforce environmental standards and fine the hell out of corporations when they violate. Sorry, but free markets don't work for everything.

  • by Anonymous Coward on Wednesday December 27, 2006 @09:26PM (#17383286)
    You could always say, split water and store the hydrogen
  • Re:Energy... (Score:2, Insightful)

    by tepples (727027) <> on Wednesday December 27, 2006 @09:40PM (#17383370) Homepage Journal

    Since when do we measure energy in gallons?

    Since the density and molar mass of diesel and the enthalpy and entropy of the diesel combustion reaction were discovered.

  • by cartman (18204) on Wednesday December 27, 2006 @10:13PM (#17383524)
    Only if you can burn the product in current systems, otherwise you have to factor in the conversion costs. And you have to assume oil prices will still be insane when your production makes it online. I'd bet on oil remaining high for a while personally, not sure how many billions I'd bet though.

    Biodiesel blend (10% biodiesel) can be burned in current cars with no modification, and pure Biodiesel (100%) can be burned in current cars with slight modifications. Newer cars could be built to accept 100% biodiesel with very little additional cost (less than $30).

    Furthermore, the current gas stations and infrastructure could still be used.

    How moronic do they make Greens these days? Yea that pond scum will absorb a lot of CO2... and release it right back when you burn it for fuel. So it is carbon neutral unless you plan to compact the algae into bricks and bury it.

    No. Algal biodiesel is carbon neutral if you burn it, because burning it emits the same amount of carbon as was removed from the atmosphere by growing the algae. Algol biodisel would be carbon negative if you buried it, because that would be taking carbon out of the atmosphere.

    Stories like this are why I don't worry about running out of oil or about global warming. Anytime the system begins to get unbalanced it forces a correction through the free market, and it works even faster and better when the government stays the hell out of things and allows nature to take its course. As oil becomes more expensive, potential replacements that used to be discarded as uncompetitive start looking viable.

    We definitely don't have to worry about running out of oil. There are many alternatives which exist and which are practically inexhaustible and which become economical once gasoline is pricier than $4/gallon. $4/gallon would hardly spell the end of civilization. All of this crap about impending doom from oil exhaustion is so silly as not to merit further comment.

    However, the market would not correct global warming, because CO2 emission is an externality. In other words, the cost of destruction from carbon emission is not charged to the emitter and therefore is not included in corporate balance sheets. Thus, the market pays no attention to it. In this case, the most appropriate response is a minimal government intervention of replacing income taxes with carbon taxes. By doing so, the gov't would internalize the externality, thereby causing it to be included in corporate balance sheets. At that point, the market would resolve the problem without further intervention.

    The investors in algal biodiesel are probably assuming that the government will impose carbon taxes sometime soon. If the government did so, then biodiesel would be much cheaper (it could help coal plants reduce their taxes) and gasoline would be more expensive, thus biodiesel would suddenly become price-competitive.

  • by Anonymous Coward on Wednesday December 27, 2006 @10:38PM (#17383674)
    Batteries still suck.
  • Re:Uhhh... (Score:5, Insightful)

    by PCM2 (4486) on Wednesday December 27, 2006 @10:51PM (#17383746) Homepage
    Free markets fail whenever externalities exist. So the free market is incapable of solving Global Warming without Government.

    You might want to actually read the article you posted in your own link. Free markets do not just fail whenever externalities exist. If that were true, capitalism itself would have failed by now. Negative externalities do tend to create "less socially optimal" situations, but that doesn't mean that market forces can't correct for them, either. I agree, however, that it seems unlikely that corporate enterprise is likely to spontaneously create a solution for global warming.

  • by Jeff1946 (944062) on Wednesday December 27, 2006 @11:00PM (#17383806) Journal
    A major bottleneck in plant growth is nitrogen, hence fertilizer. Ponds grow lots of algae when there is runoff from farms. A famous chemist once told me that half the nitrogen in our bodies comes from man-made nitrogen sources. Currently we use hydrogen made from natural gas to react with nitrogen from the air to form ammonia which is converted to various forms of fertilizer. Yes there are nitrogen fixing bacteria that do this for us but I don't believe they can do this rapidly enough for the production rates the authors propose. Just one more reason humanity is going to be SOL when oil and natural gas are in short supply.
  • Re:Uhhh... (Score:5, Insightful)

    by radtea (464814) on Wednesday December 27, 2006 @11:50PM (#17384074)
    So the free market is incapable of solving Global Warming without Government.

    What is this "the" free market of which you speak?

    All markets are made by laws, and laws are made by governments. There is no "the" free market, any more than there is "the" internal combustion engine. Markets are machines, made by human beings to solve human problems. Laws made by governments are the mechanism by which we define markets. There are no markets in nature; without governments, there are no markets at all.

    So to set "the free market" up as being in any way opposed to "Government" is to fundamentally fail to understand the nature of the relationship between the two. All markets are created by governments or quasi-government (i.e. violent) forces. They are shaped by various forms of regulation, including incorporation requirements, insurance requirements, and other things. "Free" markets are more-or-less free of overt governmental price-fixing and other direct political interference of the type Haliburton depends on. But there are many free markets of various types. And all of them depend on laws and therefore government for their existence and operation.
  • by dorbabil (969458) on Thursday December 28, 2006 @12:54AM (#17384392)
    >How moronic do they make Greens these days? Yea that pond scum will absorb a lot of CO2... and release it right back when you burn it for fuel. So it is carbon neutral unless you plan to compact the algae into bricks and bury it. Of course neutral still beats burning dead dinosaurs who fixed their carbon millions of years ago.

    Haven't you ever heard of the carbon cycle? Lots of CO2 in the air doesn't cause global warming. Global Warming occurs when we are pumping so much CO2 into the air that we break the carbon cycle.

    Basically, the primary carbon sink that occurs is algae. As algae (or animals that consume algae) dies and floats to the bottom of large regions of water, carbon is sequestered. The more CO2 that's in the air, the more algae a particular region can sustain. This creates a self-sustaining feedback loop that prevents any dramatic changes in the mean global temperature. It's only when this feedback loop can no longer keep up that global warming (or global cooling, in the opposite case) occurs.

    Other natural and human events can alter the carbon cycle. Fertilizer run-off can cause a major algae bloom, which chokes out the O2 in a particular region of water, and results in dead space. This reduces the amount of future algae growth, and decreases the cooling ability of the cycle. Then there are issues with smog, volcanic erruption, and things of that nature.

    So anything that is carbon neutral is a huge step forward from where we're at now. The sooner we stop pumping new CO2 into the atmosphere, the more likely it is that the carbon cycle will be able to control the mean global temperature.
  • by cybpunks3 (612218) on Thursday December 28, 2006 @05:10AM (#17385482)
    Oil was probably once algae. The problem with bio oil is the rate at which nature produces oil products is not high enough to substitute for the rate of extraction of oil and gas. So it's really a problem of demand, not supply. The demand is caused by industrialization and population growth. As long as the human population increases, technology will have to get more and more exotic for the planet to be able to sustain us, and most other lifeforms will probably go extinct without our direct protection.

  • Go to Somalia. (Score:3, Insightful)

    by Grendel Drago (41496) on Thursday December 28, 2006 @02:02PM (#17389534) Homepage
    Oh, so you'd like to live your life free from the baleful mailed fist of government? Move to Somalia.

The perversity of nature is nowhere better demonstrated by the fact that, when exposed to the same atmosphere, bread becomes hard while crackers become soft.