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Power Science

Newest Energy Source — Pond Scum 289

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 Colin Smith ( 2679 ) on Wednesday December 27, 2006 @06:37PM (#17382020)
    Generate electricity for these: []

    or these: []

    And everything else. Then you don't have to bugger about expending energy processing it the stuff into biofuels.

  • by Scarblac ( 122480 ) <> on Wednesday December 27, 2006 @06:38PM (#17382046) Homepage

    Very interesting, thanks!

    From a quick scan - "Even with aggressive assumptions about biological productivity, we project costs for biodiesel which are two times higher than current petroleum diesel fuel costs".

    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.

  • Dirty Jobs (Score:5, Interesting)

    by MBCook ( 132727 ) <> on Wednesday December 27, 2006 @06:39PM (#17382052) Homepage

    There was something a bit like this on Dirty Jobs as I remember. It was a research project that took the output of a power plant (a portion of it) and ran it though tubes of algae that would filter it and remove CO2 and grow, then they could burn the algae afterwards. That way they could get the "free" energy (from the sun that the algae was storing) plus is was carbon neutral if implemented on a large scale.

    We just have to be careful that while we enslave the algae, they don't know it's happening so they don't start an uprising. I don't want a very thin layer of mad green goo covering everything.

  • Uhm..Yield rates. (Score:4, Interesting)

    by The Living Fractal ( 162153 ) <banantarr@hotmail . c om> on Wednesday December 27, 2006 @06:59PM (#17382230) Homepage
    The article talks pretty high of this algae. Acres upon acres of biodiesel creating algae for all!

    It seems pretty biased to me. No mention of the energy required to run the biodiesel plants. No mention of exactly how long each yield cycle takes. I mean, great, 10k gallons of biodiesel (even up to 20k) per acre.. per how long? It's a measure of time I thought? So why are you giving me these one-dimensional 'rates'. Sounds pretty skim on the details.

    And let's talk about acres. I'd rather cover an acre of desert with solar panels than an acre of land in more moderate climates. And now I get led into the question of solar vs. algae. The algae gets its energy from photosynthesis. Great. But can an acre of algae really compete with an acre of the highest efficiency solar cells -- again, over time? Which one wins in the end?

    Look, I'm not saying I disagree, I think it's great people are pursuing alternate forms of fuel. But if you're going to write an article and call it news the least you could do is play devil's advocate along side fanboy. Give me some compare and contrast, some pros and cons. That's all I want!

  • Already doing it (Score:3, Interesting)

    by Xybot ( 707278 ) on Wednesday December 27, 2006 @07:05PM (#17382288)
    Been there, done that []. Next you'll be telling us the the first controlled flight [] took place in America.
  • Surprising numbers (Score:5, Interesting)

    by edwardpickman ( 965122 ) on Wednesday December 27, 2006 @07:18PM (#17382380)
    If the 100,000 barrels per acre is even close to accurate there's more than enough hog waste to produce what biodiesel we need. I single factory farm could provide enough for hundreds of acres of algae ponds. Nitrogen is miracle grow for algae so farm waste could be the new middle east. I'd read about this process years ago but the numbers seem much better than I could have imagined.
  • Re:Uhm..Yield rates. (Score:4, Interesting)

    by mangu ( 126918 ) on Wednesday December 27, 2006 @07:18PM (#17382390)
    But can an acre of algae really compete with an acre of the highest efficiency solar cells -- again, over time? Which one wins in the end?

    Considering that the algae aren't black and reflect a lot of the sunlight, I would guess the solar cells win. But how about the total cost? You are considering only land cost, if the algae are less efficient, more area will be needed for them. However, algae are self-manufacturing, solar cell must be produced in a factory from a number of different machines and raw materials. 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.

    All in all, I'm pretty sure algae would be cheaper in our current technology level. Certainly more efficient manufacturing processes for solar cells will be developed in the future, but for now I'd be willing to bet that the total cost for generating energy is lower for algae than for solar cells.

  • by WrongMonkey ( 1027334 ) on Wednesday December 27, 2006 @07:27PM (#17382468)
    I think that it is worth noting that the 10,000 gallons per acre estimate assumes that the algae will have a gas feed from a coal power plant. It would be more apt to compare the tield of this process to direct generation of liquid fuel from coal since it's essentially generating it indirectly. Other questions unanswered by TFA: Are there enough coal plants in the country to support a total replacement of gasoline by this method? Does it affect the efficiency of the power plant? How long will our coal resources last if this were implemented on a large scale? What are the maintainence costs (hard to estimate from a test setup, but important to consider)?
  • by jmorris42 ( 1458 ) * <> on Wednesday December 27, 2006 @07:31PM (#17382514)
    > If that was in 1998, then at should be very feasible with current petrol costs,

    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.

    > especially taking into account the added value of removing CO2 from the atmosphere.

    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.

    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. Once one gets established the intense competition that drove the cost of oil production down will make the new thing cheap and plentiful.
  • by StikyPad ( 445176 ) on Wednesday December 27, 2006 @07:37PM (#17382566) Homepage
    Actually, that would be third-dimension, since acres are two dimensional units.

    Anyway, duckweed [] doubles its biomass in 10 days []. It's one of, if not the fastest growing plant known (which explains why it's such a pest in our backyard pond). However, since algae need not remain on the surface, the water could be agitated to perhaps increase the usable volume in which the algae grows. That probably wouldn't work for duckweed which a) floats very well, and b) has a sort of floating root which would cause problems. But if it grows faster, it might not matter -- assuming it's usable in the first place.
  • vastly overlooked (Score:2, Interesting)

    by lwiniarski ( 105158 ) on Wednesday December 27, 2006 @07:38PM (#17382574)
    I don't think people realize that how important this is. I converted my van to run on
    raw vegetable oil and have been quite happy with it. I can easily see this replacing
    mineral oils in a relatively short time. It is becoming more and more popular as
    diesel prices keep increasing.

    Biodiesel is basically chemically altered vegetable oil that reduces viscosity
    (transesterfication) but is not necessary if you modify your diesel to reduce the viscosity
    by heating the oil to around 200F.

    While electric cars are super neato and probably our long term solutions, I can see
    imagine that it's gonna be pretty hard to make an electric powered jet airplane, but
    I think an algae oil powered jet airplane might be pretty reasonable. After all
    kerosene (used for jet fuel) is very similiar to diesel #1.
  • by xs650 ( 741277 ) on Wednesday December 27, 2006 @08:15PM (#17382868)
    The remaining biomass should be considered a feature rather than a bug. Most dried bio-mass has an energy content of about 4,000 BTU/lb, about the same as wood and roughly 1/2 that of coal.

  • by Your Pal Dave ( 33229 ) on Wednesday December 27, 2006 @08:21PM (#17382904)
    Depends upon the algae. Diatoms are 40% oil.
  • supply/demand (Score:3, Interesting)

    by Anonymous Coward on Wednesday December 27, 2006 @08:21PM (#17382906)
    This is basic economics. Oil companies make more money with less work by keeping supplies low. Demand is always there, that isn't a problem at all, so they juke the market by not producing more oil. It's dogsquat simple in concept and makes them uberbillions every quarter. They don't want to work harder for less money per work unit. no one wants to do that really. Do you? Would you go out of yur way to put yourself out of a job? That's what you are thinking the oil companies should do, and guaranteed, most of them hates that idea. And it is in their economic capitalist interest to work as hard as they can behind the scenes to sabotage any alternative energy project which threatens their cartel monopoly on transporation energy. They are OK with "studies" as long as the studies last 30 years and result in more studies. Dig it?

    BP is an example (one of the very, very few) of an energy company that used to be just an oil company, but they "seen the light" and now are "energy", hence their commitment to oil, solar and windpower and whatever else looks good and they have been working along those lines for several years now. Exxon is an oil company only and have testified (their last *disgusting* parasite bloated tick CEO who got the 400 million buck severance package) in front of the senate to this effect. They have no interest whatsoever in anything else, because that means they would have to go work harder and invest their profits in new infrastructure instead of enjoying the cash as they see fit with private jets, yachts booze and hookers and they think "FU, we don't have to do anything you want us to do, because we got what you need,an we run the government for the most part,so suck it up trapped consumer and turn over your wallet to us".

      They work on the artificial scarcity & controlled government model of capitalism.
  • by Martin Blank ( 154261 ) on Wednesday December 27, 2006 @08:52PM (#17383094) Homepage Journal
    The economics are vastly different from what they expected them to be (big surprise). They have to buy the feedstock in this case, whereas in most other developed countries, they would be paid to take the feedstock (the US allows turkey offal to be fed back to turkeys, whereas most developed nations have banned cannibalistic feeding), and until the beginning of this year, they didn't get any form of tax break for biodiesel. A follow-up article [] suggests multiple plants could be operational in Europe in the next few years, including one optimistic viewpoint of a $70 per barrel profit margin (significantly higher than I think it will be, but even a third of that would be respectable).

    The efficiency comes from the fact that the feedstock contains significant quantities of water, which of course have to be removed from the final oil product, lowering the apparent efficiency (in this case by perhaps half) yet still realizing a profit, according to recent articles, of a few dollars per barrel. The final output may differ significantly from what was expected and have it still be a viable process.
  • by Thomas the Doubter ( 1016806 ) on Wednesday December 27, 2006 @09:54PM (#17383454)
    Did you say "dried" biomas? I think it would not be easy (cheap) to dry vast quantities of algae, except, perhaps, maybe in the desert.
  • by Surt ( 22457 ) on Wednesday December 27, 2006 @09:56PM (#17383466) Homepage Journal
    Just commenting on your sig:
    You've probably gotten banned from moderation. You can get this most commonly by having used your modpoints negatively on a slashdot editor's post.
    Once you're banned, you'll never see mod points again.

  • by maeka ( 518272 ) on Wednesday December 27, 2006 @11:11PM (#17383872) Journal
    It doesn't need fresh water, you can grow algae in sea water -- something our world still has no shortage of.

    You can irrigate it with sea water once. When the water evaporates leaving the salts behind, you are in a bit of a pickle.
    Even with "fresh" water irrigation the accumulation of salts is going to be a very real issue.
    Another poster suggested growing the algae "indoors" to recycle the water. While this may solve the salt accumulation issue, it does dramatically increase the start-up costs.
  • by alizard ( 107678 ) < minus city> on Thursday December 28, 2006 @01:33AM (#17384610) Homepage
    The kind of manufactured goods required to build such a thing also cost less than they did 4 years ago.

    The assumptions have also changed since the 1990s, for instance, open ponds are obsolete due to problems with species control and going to enclosures means one can better control bioreactor conditions. Researchers are claiming 10-20x increases in yield due in part to this. Bottom line: higher capital cost vs MUCH higher yield per acre.

    It's also the only game in town, it's scalable to installations with yield sufficient to grow 400M gallons per day. We don't have enough farmland to grow our way out with bio-ethanol, even using switchgrass and marginal farmlands.
  • by evilviper ( 135110 ) on Thursday December 28, 2006 @03:58AM (#17385244) Journal
    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?

    Lots of subsudies for oil and hydrogen. None for "algae biodiesel".
  • by Colin Smith ( 2679 ) on Thursday December 28, 2006 @09:32AM (#17386626)
    It gets better.

    An electric vehicle has almost no moving parts. There's the bearings, the motor, brakes and that's about it. There are no valves, no cams, no crank, no pistons, no piston rings, no spark plugs, no distributor, no air filters, no oil, etc etc to service every 10,000 miles. They don't even really need a gearbox. Basically it should just run and run and run as long as the battery lasts, and the Altair Nano lithium titanate battery is rated for thousands of charges, ~25 years.

    So you have bugger all power costs, you have bugger all servicing costs. The cost per mile basically comes down to the power plus capital cost over the lifetime of the vehicle, and there's no reason it shouldn't do a million miles with the occasional replaced tyre, brakepad, windscreen wiper and maybe a bearing every 100,000 miles.


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