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Power Transportation Science

Algal Biofuels Not Ready For Scale-Up 179

Tator Tot writes with this quote from Chemical & Engineering News: "Using today's technologies and knowledge, a scale-up of fledgling algal biofuel production sufficient to meet even 5% of U.S. transportation fuel demand is unsustainable, says a report released last week by the National Research Council. The report examines the efficiency of producing biofuels from microalgae and cyanobacteria with respect to energy, water, and nutrient requirements and finds that the process falls short. The energy from algal biofuel, the report finds, is less than the energy needed to make it. In terms of water, at least 32.5 billion gal would be needed to produce 10 billion gal of algae-based biofuels, the report states. The study also finds that making enough algal biofuels to replace just 5% of U.S. annual transportation fuel needs would require 44–107% of the total nitrogen and 20–51% of the total phosphorus consumed annually in the U.S."
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Algal Biofuels Not Ready For Scale-Up

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  • Re:In other words... (Score:5, Interesting)

    by Joce640k ( 829181 ) on Friday October 26, 2012 @12:23PM (#41779437) Homepage

    Wouldn't most of that nitrogen/phosphorus be recycled into the next generation of algae after extraction of the fuel?

    ie. Once the cycle is started it doesn't take anywhere near that amount to keep it going.

  • Sewage (Score:4, Interesting)

    by LunaticTippy ( 872397 ) on Friday October 26, 2012 @12:28PM (#41779523)
    We flush whole shit-tons of water, nitrogen, and phosphorus down our toilets. Why not turn that into biofuels? Cities will pay good money for you to process their waste, and you can charge for the fuel, too.
  • by Grayhand ( 2610049 ) on Friday October 26, 2012 @12:29PM (#41779541)
    Okay how's this for some numbers. It takes 2,500 gallons of water to produce one bushel of corn. That doesn't include processing to ethanol. Oil also takes huge quantities of water to produce refined gasoline or diesel. They are talking 3 to1 for biodiesel from algae. That's actually impressive! Also they assume we'd use chemical fertilizers. Why? Most proposals I've seen used farm waste especially pig waste which goes to waste and pollutes rivers. There's a frightening amount of farm waste, both pig and chicken, that could be used for algae production. FYI, some types of algae live in brackish water and there is effectively an unlimited supply of that. Most of the extraction techniques involve squeezing out the oil with maybe a small amount of alcohol used to soften the cell walls so there's limited energy needed in processing. If you cherry pick data you make the numbers sound scary.
  • Re:Sewage (Score:2, Interesting)

    by Kreigaffe ( 765218 ) on Friday October 26, 2012 @12:42PM (#41779729)

    Good question. Seeing as how this stuff wouldn't ever come into contact with food, seems like an ideal use to me.
    If it at least would produce enough energy to keep itself running, functioning as a waste disposal plant would still be useful.

    Or hell, use the Mississippi. There's tons of fertilizer that gets flushed into the Gulf and isn't doing its ecosystem any favors. Run it through some shit that'll eat up the excess first, why not.

  • Re:English (Score:5, Interesting)

    by gstoddart ( 321705 ) on Friday October 26, 2012 @12:43PM (#41779735) Homepage

    Why? It's a perfectly cromulent word.

    We use "fungal" to describe "fungus-based", what is wrong with algal? One sees "algal bloom" fairly often.

    Are we trying to dumb down science for the lowest common idiot now?

  • by Anonymous Coward on Friday October 26, 2012 @12:50PM (#41779827)

    Here's something: (in a simplified nutshell)

    Those corn subsidies make US corn really cheap, which is then exported to Mexico. The Mexican farmers couldn't compete and went out of business. So to make ends meet, those million+ farmers came to the US to make some money and then are treated like criminals - all because of farm subsidies.

    Talk about unintended consequences.

    Next up: farm subsides destroying Gulf fisheries requiring more subsides to fishermen.

  • Re:In other words... (Score:5, Interesting)

    by Anonymous Coward on Friday October 26, 2012 @12:55PM (#41779881)

    Yes, and and the assumption they make is that algae requires the same levels of both nutrients as regular crops do, which it doesn't. They are also basing their conclusion on a study that DOE did with open ponds, not considering the advancements the closed PBR's have made in recycling the water and with growth rates. Algae offers many advantages that almost all other "green" energy sources lack: primarily it absorbs a lot of CO2, it grows best in waste water (think sewers), can be used for both bio-diesel and bio-butanol, and the pressings can also be used as fuel for pellet type heaters, used as fertilizer as well as feed supplement. Another thing about algae is that you don't have to use land to produce it, we have vast tracks of ocean that floating PBRs could be deployed in and use filtered sea water which has all the nutrients needed. Algae fuel is the best of all the green energy scenarios, its is liquid stored solar power, so you don't need batteries, don't need new storage and delivery infrastructure and in one stroke solves global warming. We just need to put forth the effort and do it.

  • by hey! ( 33014 ) on Friday October 26, 2012 @01:18PM (#41780211) Homepage Journal

    Now imagine the people in that world imagining what it would take to create a petroleum-based economy like ours from scratch. The amazing drilling technology; the massive investment in super-ships and pipelines; the scale and sophistication of refineries; the ubiquitous distribution networks; the engine technology to burn petroleum cleanly and efficiently.

    Imagining all those things happening in the space of, say, ten or even twenty years would be impossible. And in fact it didn't happen that way. It took us more like a century.

    People seem to be daunted by any new energy technology because they can't imagine it replacing petroleum overnight. But it doesn't have to happen that way, and in fact it won't. The dominance of petroleum we've known all our lives will be gone someday, probably within the lifetime of some people alive today but that might be fifty years or more into the future. And as with any technology, success with the replacement technologies will depend on timing. You wan to be ahead of the curve, but not investing so far ahead of the curve you're dealing with impracticability. Back in '94 I worked for a new boss who was betting the company on the emergence of something like Netflix streaming in the next year or two. I explained all the difficulties and why it would not happen any time in the next decade, but she was so certain it was going to happen she could not be dissuaded (so I quit). I envisioned the same future as her, but I thought her timing was premature -- as it turned out to be by some 14 years.

    Apple's success is, apart from design, largely a matter of timing. They weren't the first to develop a tablet, but the iPad came when it was possible to make something thin enough, light enough, long-lasting enough and powerful enough to be useful. People who tried when you needed to make the things ten pounds and an inch thick to accommodate the battery failed, no matter how impressive their design was for the time, because he time was wrong.

    As I said, petroleum will fade away in the lifetime of many of us, and what replaces it would seem astonishing to us today, but it won't happen overnight. And we'll never run out of oil. We'll use less and less of it as the prices rises against the falling price of the alternatives. At the outset, those alternatives won't look competitive at all. And most of them will never be competitive. The few that will work out will be very difficult to pick out from the rest of the pack of doomed technologies.

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