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Earth Science Technology

Researchers Pooh-Pooh Algae-Based Biofuel 238

Julie188 writes "Researchers from the University of Virginia have found that current algae biofuel production methods consume more energy, have higher greenhouse gas emissions and use more water than other biofuel sources, such as switchgrass, canola and corn. The researchers suggest these problems can be overcome by situating algae production ponds behind wastewater treatment facilities to capture phosphorous and nitrogen — essential algae nutrients that otherwise need to come from petroleum."
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Researchers Pooh-Pooh Algae-Based Biofuel

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  • Reserachers? (Score:5, Informative)

    by azav ( 469988 ) on Thursday January 21, 2010 @04:59PM (#30851164) Homepage Journal

    Timothy, please spell check your title.

  • Hydroelectric (Score:3, Informative)

    by Rix ( 54095 ) on Thursday January 21, 2010 @05:04PM (#30851280)

    And besides, they don't build nuclear plants in the city, they build them out in the middle of nowhere.

  • by John Hasler ( 414242 ) on Thursday January 21, 2010 @05:07PM (#30851326) Homepage

    > ...phosphorous and nitrogen -- essential algae nutrients that otherwise need
    > to come from petroleum.

    Phosphorus and nitrogen from petroleum. Uh huh. Right.

  • by Anonymous Coward on Thursday January 21, 2010 @05:15PM (#30851508)

    When you see that growing corn to produce ethonal requires petroleum, do you assume that they dump petroleum on the corn fields? No, you assume that petroleum is required to run the tractor, run the truck that delivers the fertilizer, or heat the reactor vessle that makes the fertilizer.

    Assume this means that petroleum must be consumed in the delivery mechanism for phosphorus and nitrogen. Perhaps because they need to drive a truck to deliver it, or maybe the chemical reaction to fix it requires petroleum or burning petroleum, or whatever. Obviously it doesn't mean that these elements are extracted directly from petroleum.


  • by nweaver ( 113078 ) on Thursday January 21, 2010 @05:24PM (#30851668) Homepage

    Diesel, wholesale, is a couple bucks a gallon. Which means it is far FAR less than a dollar a pound.

    A good algae is worth far MORE than that per pound as animal feed, dietary suppliments, etc. So why turn something that you can sell for $2/lb into something you can only sell for less than $.5/lb?

  • That's interesting (Score:4, Informative)

    by Useful Wheat ( 1488675 ) on Thursday January 21, 2010 @05:27PM (#30851746)

    The company that I worked for commissioned a few studies on algae based biofuels. It turns out that the most efficient way of handling the material was to collect the algae in cakes and burn it in a reactor to make synthesis gas. Synthesis gas is a mixture of CO and Hydrogen. If you add steam, you could then perform a shift reaction to get methane or methanol. The main value of the process was not in producing fuel, or generating electricity. The main thing you could use it for was as a chemical feedstock. Methanol is a good starting point for many plastics.

    (final comment, my spell checker wants to change biofuels to befouled)

  • by Red Flayer ( 890720 ) on Thursday January 21, 2010 @05:28PM (#30851768) Journal
    OK, so whoever wrote that wasn't thinking straight. But it is true that fertilizer (both phosphates and nitrogen) require a lot of fossil fuel to produce -- usually natural gas.

    Phosphate fertilizer (ortho- or poly-phosphates) is synthesized in an energy-intensive process. Organic phosphates, like those from manure (or waste treatment plant effluent), help solve this problem.

    For nitrate fertilizer, it's even more extreme. Please read about the Haber Process [].

    Yes, John, most fertilizer does come from fossil fuels.

    So, yes, whoever wrote that made a mistake. However, it's no lie to say that fertilizer production uses a huge amount of fossil fuel.
  • by homer_ca ( 144738 ) on Thursday January 21, 2010 @05:43PM (#30852070)

    Nitrogen fertilizer (ammonia) is made from natural gas through the Haber Bosch process. Phosphorus is produced in a relatively small number of huge mines and shipped around the world by a supply chain powered by oil

  • Population size (Score:3, Informative)

    by geek2k5 ( 882748 ) on Thursday January 21, 2010 @05:49PM (#30852176)

    Population size makes a big difference. It wasn't until around 1800 that the population of the Earth was close to 1 billion. We're now adding that many people in less than 20 years but we are NOT adding enough land to take care of that increase.

  • Re:Hydroelectric (Score:3, Informative)

    by QuantumRiff ( 120817 ) on Thursday January 21, 2010 @05:54PM (#30852276)

    Hey, cool, that's just a few blocks down the road...

    On a side note, Oregon State University in Corvallis, OR, and Reed College, in Portland, OR, both have reactors on campus. the Reed college one, you don't have to be in an engineering program to use it!

  • by cheesybagel ( 670288 ) on Thursday January 21, 2010 @05:57PM (#30852342)
    No. The Haber ammonia synthesis process requires a source of hydrogen to run. It is just that currently the cheapest way to generate hydrogen is steam reforming of natural gas. Natural gas, not petroleum. Hydrogen can just as well be generated from electrolysis (if you have cheap electricity), sulfur-iodine cycle (if you have an available source of heat), or whatever from water.
  • Salt Water Biofuel (Score:5, Informative)

    by EEPROMS ( 889169 ) on Thursday January 21, 2010 @06:26PM (#30852886)
    I notice a few people commenting on using fresh water. Well according to CSIRO (Australia) you can happily use salt water [] There is even a prototype plant that has been commissioned [] to look at making this more cost effective.
  • by Anonymous Coward on Thursday January 21, 2010 @06:31PM (#30852956)

    Which gets carried away gradually by the wind ... which flies way over your head.

  • Rehash (Score:2, Informative)

    by tngaijin ( 997389 ) on Thursday January 21, 2010 @06:34PM (#30853010)
    This sounds like the University of Virgina is just regurgitating information published by Michael Briggs of the University of New Hampshire. [] This isn't really a new idea nor a new recommendation. It is sad that it is at least 6 years old and it is being treated as new information though.
  • by Diss Champ ( 934796 ) on Thursday January 21, 2010 @06:34PM (#30853012)

    To make fertilizer, you want fixed N (that is, N that is connected to carbon). Doing that is a big part of the energy cost in the fertilizer.
    (this doesn't mean you can't come up with an algae good at fixing N; but there's plenty of N around anyway, N2 is most of our atmosphere. Such would be a good starting point for using algae to make fertilizer. My point is what we're really trying to get out of the algae is energy, which making fertilizer also requires).

  • by MrNiceguy_KS ( 800771 ) on Thursday January 21, 2010 @06:34PM (#30853018)

    I think you've over-estimated the chance in being Barack Obama by quite a bit. Your estimate for being hurt by a nuclear power plant seems right on, though.

  • by khallow ( 566160 ) on Thursday January 21, 2010 @06:44PM (#30853174)

    Natural gas is often processed with petroleum as they are often in the same fields. Processing natural gas into hydrogen (steam forming) requires energy. The Haber Process requires energy. Most often electricity is required to run the machinery. The vast amount of electricity comes from fossils fuels.

    Neither the hydrogen nor the electricity come from petroleum. Most fossil fuels and hydrogen sources are not petroleum. These distinctions matter in some areas like a consideration of the effects of radical oil supply drops (commonly called "peak oil").

  • by hey! ( 33014 ) on Thursday January 21, 2010 @06:53PM (#30853334) Homepage Journal

    At the current production level.

    That's the problem with simplistic cost analyses; they ignore the fact that if a lot of something is produced, it tends to get cheaper. On the other hand the demand for algae for biodiesel would tend to drive costs up.

    The secret is that competition tends to drive costs down to "normal profit" levels. If you could sell algae cheap enough to replace diesel, sooner or later somebody will undercut the algae as feed prices, unless one company has the exclusive rights to the magic process that makes cheap algae possible.

  • by natehoy ( 1608657 ) on Thursday January 21, 2010 @07:01PM (#30853448) Journal

    I think you mean dihydrogen monoxide (DHMO for short).

    hydrogen dioxide is also known as "hydrogen peroxide", which is a relatively harmless bleaching agent, and it contains more oxygen than DHMO, so it's got to be healthy.

  • by Gordonjcp ( 186804 ) on Thursday January 21, 2010 @07:03PM (#30853470) Homepage

    That's not quite true. The vast majority of the world's livestock farms aren't on land that's suitable for arable farming. Furthermore, without the livestock farms you are wholly dependant on petrochemical-derived fertilisers and human waste for farming - but it turns out that to make human waste from sewage plants safe to use as fertiliser, you need lots of petrochemicals. Oops.

  • by Jeremy Erwin ( 2054 ) on Thursday January 21, 2010 @07:20PM (#30853746) Journal

    Ah. LPAC stands for LaRouchePAC. I thought the rhetorical style was familiar.

  • by Yergle143 ( 848772 ) on Thursday January 21, 2010 @09:21PM (#30855046)

    Good question. Even industrial rotary drum filters: []
    get clogged easily by the microscopic algae.
    Also "the container" to be economical must be these so-
    called raceway ponds and there is no "tilting" something
    the size of a farm.

    Again if you read up, algae has been a proposed source
    of fuel for a very long time. Unfortunately the devil is in the
    engineering challenges (and the biology -- this is a kind
    of agriculture but with major disadvantages in that the "weeds"
    are microscopic). It seems like every problem conspires to
    make it more expensive.

    This a link to a paper from a guy who has been in the field
    for some time (and is sceptical of the hype). []

  • by Smidge204 ( 605297 ) on Thursday January 21, 2010 @09:44PM (#30855236) Journal

    Obviously it doesn't mean that these elements are extracted directly from petroleum.

    Methane (aka natural gas, a fossil fuel) is used as the donor for the hydrogen needed for the Haber process, and releases the carbon as CO2.


  • by Anonymous Coward on Thursday January 21, 2010 @09:53PM (#30855312)

    This is actually not true. In most cases the algae are harvested (i.e. killed) to get the biodiesel out of them, because they are unable to secrete them. Even in cases where they are secreting them, there are other problems. Sun light exposure requirement means large ponds or expensive transparent reactor technologies maximizing surface area. There are 1-2 companies which are not using sunlight but using dark reactors and giving the algae food (glucose or other sugars and nutrients). That is, they use the algae for their oil producing property. So overall, it is a lot complicated than the simplistic pitches that go like 'they capture sunlight and CO2 and produce diesel'.

  • by Anonymous Coward on Thursday January 21, 2010 @10:16PM (#30855456)

    You live east of the Dakotas, don't you?

    Feedlot cattle are mostly an eastern thing. Out here cattle are grass-fed on land unsuitable for growing corn and soy. While it is true that the two largest beef-cattle states (Nebraska and Texas) raise a majority of their cattle on lots, they are the exception. Head north or west and almost 100% of the cattle is grazed.

    In 2003 only ~40% of US beef cattle was grain-fed, and of that most were only grain fed the later days of their lives.

No problem is so large it can't be fit in somewhere.