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This discussion relates to Technology Review's article Dow to Test Algae Ethanol.

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  johnsonha143
  

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  07/16/2009 07:20 AM

  Ethanol from Algae

  This is all fine and well, but what will we do with the ethanol? The article says that Dow plans to use the ethanol in the production of plastics, which is good as it will keep plastics cheap as oil goes out of favor.
  
  My concern, however, is that we will try replace gas/oil in the internal combustion engine (ICE). The ICE is far too inefficient and should be replaced by the electric motor. Therefore, I would be a strong advocate of using the ethanol to run turbines to generate electricity.
  
  My main fear is that cheap ethanol will interfere with the conversion of our transportation infrastructure from ICEs to electric motors. THIS CAN NOT BE ALLOWED TO HAPPEN! Electric motors are far more efficient than the ICE and we should vigorously pursue this conversion!
  
  HJ
  WALDORF, MD

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  • 
    bertibus06
    

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    07/16/2009 08:37 AM

    Re: Ethanol from Algae

    The engine itself may be more efficient, but everything else in the chain is not - and by a long way.
    
    In addition, bio-fuels will be needed for other forms of transportation such as aviation where the weight and energy retention capacity of batteries renders them useless.
    
    When things change, we can, as you suggested, burn the artificially produced fuel to create electricity.

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    • 
      MakeSense
      

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      07/19/2009 11:27 AM

      Re: Ethanol from Algae

      The "well-to-wheel" efficiency of electric vehicles is purported to be about 77% by NREL; whereas the same metric for ICEs is about 16%. Electricity is efficiently transported with about 7% losses on average.
      
      Even though conversion of chemical energy in coal to electrical energy is only about 35% efficient, production, refinement and distribution of refined gasoline is about the same at 45% efficiency.
      
      The huge advantage to electric vehicles is the roughly 90% efficiency of electric motors at producing work from electricity compared to about 20% for ICEs using hydrocarbons.
      
      That being said, efficiency matters less when an energy product is abundant. We rarely cared about efficiency when oil stocks were sky high. If this ethanol could be produced cheaply in vast quantities, then it might save us all a lot of effort and expense in converting to electric vehicles. Algae has the "potential" to produce truly vast amounts of diesel and ethanol fuels.
      
      It would be impractical to produce electricity from biodiesel or bioethanol, simply because they are already useful - and likely expensive - energy products. Only 35% of the energy would become electricity after much initial energy expenditure.
      
      I'd like to see electric vehicles take over as the best way to reduce dependence on oil. Afterall, over 40% of oil has non-highway uses, which will grow another 35% by 2030. If we eliminated oil use for highway transportation, we would still import over 60% of our 2030 oil. Perhaps algal diesel and ethanol can offset industrial, residential and commercial needs (nominally) for oil.

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  • 
    kstauff
    

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    07/16/2009 09:55 AM

    Re: Ethanol from Algae

    While I agree with you on the electric motor's efficiency at converting electrical energy to mechanical energy, I still see a place for ICE's in series hybrid vehicles like the Volt.  If an ICE can be used to turn a generator in an optimal power band, then it can run far more efficiently than if it is used as the vehicles power plant directly.  This arrangement allows for all of the benefits of electric propulsion (torque, braking recovery) with the benefit of energy dense fuel that can extend the range of the vehicle.

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  • 
    HowieSeattle
    

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    07/16/2009 01:44 PM

    Re: Ethanol from Algae

    Think fuel cells. Ethanol is a prime candidate for use in fuel cells.
    
    Like it or not liquid fuels are here to stay.
    
    On top of that this Algae seems to grow in Salt water, meaning you can put these farms on floating platforms and not only produce fuel, but Fresh water, which is something that So. Cal. needs badly. This technology seems to be the Hat Trick of biofuels.
    Doesn't compete with food crops
    Makes Fresh Water
    Provides Ethanol and at a reasonable price.

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  pzkrakz
  

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  07/16/2009 09:45 AM

  [no subject]

  Well, the point is that they can do three useful things with this technology:
  
  1 - Sequester C02 industrial output
  2 - Generate ethanol at a price point comparable to where we will be with cellulosic fermentation
  3 - Desalinate salt water
  
  While I agree that electric vehicles are where we are headed, and liquid fuels unecessary (at least for cars), this is still a very useful platform they have developed.
  
  It brings up another interesting point - if they can sequester carbon into plastics, while desalinating water, then perhaps we should move back to non-biodegradeable plastics.  Sure, it will litter the landfills permanently, but at least the carbon is out of the atmosphere.

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  kstauff
  

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  07/16/2009 09:51 AM

  [no subject]

  Does anyone else here see a problem with scale?  We're talking about 3100 tanks on 24 acres to produce 100k gallons.  At that scale it would take 240,000 acres to produce 1 billion gallons of ethanol and 31 million of these tanks.
  

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  • 
    ericzundel
    

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    07/16/2009 10:44 AM

    Re:

    To produce food in the US, we use 94 million acres of farmland.  My back of the napkin calculation says it takes .35 b bushels of corn /billion gallons of ethanol w/ an average of 183 bushels/acre == 1.9m acres/billion gallons of ethanol. 240k acres/billion gallons of ethanol doesn't sound bad to me (375 mi^2 or 971 km^2.)    The land doesn't have to be arable land either - you just need access to sunlight and some kind of water source.    Heck, it doesn't even *have* to be land at all, does it?
    
    Compared to growing corn for ethanol, if the figures quoted in the article actually pan out, it sounds like a much better option from both an efficiency to produce standpoint, and number of acres to produce.

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    • 
      erbium
      

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      07/16/2009 04:16 PM

      Land area

      Yes, there are 3.7 million square miles in US.
      
      http://www10.wolframalpha.com/input/?i=united+states
      
      so 375 square miles is approx 1/10,000 th of the total land area.
      
      Sounds good to me!
      
      sequestering this as plastics can be expanded to ANY carbonaceous compounds.   Carbon fibers are incredibly strong and a car panel made of carbon fiber weights only 20% that of metal equivalent.
      
      I forsee that we will use the carbon compounds created this way in a huge variety of ways.  Not only plastics but reinforcing fibers for concrete,  carbon based or reinforced 'sheet rock', carbon girders for homes that are not only lighter than steel but don't rust and are more quake resistant possibly. 
      
      If we put carbon emitted into carbon materials then this could balance out CO2 in the atmosphere.  With 3 teratons of Co2 in atmosphere, reducing it to the historic recent average of perhaps 2 teratons gives around a teraton or more that could be put into building materials for houses, planes, cars, bikes,, maybe even ships. 
      
      heck ships have been made of concrete, and fiberglass so carbon is a natural.

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      • 
        mkogrady
        

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        07/17/2009 01:54 PM

        Re: Land area

        There are millions of square miles of useless land that can be used for these bio-reactor farms to be placed. The lands off the Salton Sea near San Diego offer access to the brackish for salt water (oil exploration tools could drill a "well" to the Gulf to get more), lots of bright sunny skies unfettered with towering sky scrapers and it's cheap!  There are millions more acres south of Yuma too, but they're in Mexico's Sonora Desert on the bay. Building a pipeline from the shore area to Yuma would be pretty simple (except for the violent criminals controlling the border towns). We did this for OPEC, why not Mexico?
        
        Besides, our Military could patrol this region of the world a heck of a lot more effectively than what we do in the Middle East, and the troops could drive home on weekends to relax!

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    • 
      mkogrady
      

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      07/17/2009 02:00 PM

      Re:

      I agree Eric - see my comments below on Yuma, Salton Sea and Mexico.
      
      This is a much better solution than fuels derived from farm crops like corn, barley and other grains. Plus this produces fresh water that in itself is a much more valuable commodity.

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    • 
      jfinlayson
      

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      07/20/2009 05:59 PM

      Acres

      Land use isn't the issue with algae bioreactors.  The most difficult barrier to overcome is capital cost.
      
      Comparing acres of cropland to acres of bioreactors doesn't address capital cost.  It's cheap to scatter seeds over a 100 acres of land.  The cost of building the bioreactors, pumps, plumbing and other systems to cover the same 100 acres is very high.
      

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  • 
    suejonez
    

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    07/17/2009 09:49 PM

    its light, not land

    Story is missing the number that would make it interesting-- How efficient the algae is at converting sunlight to useful products?   Answer is usually around 4%.  Solar panels are 24%, so you don't want to do this for electricity.  It makes sense if you need ethanol-- it should be way better than using corn and coal to make ethanol which is the primary way it is done now. 
    
    You don't want to do this long term for transportation fuel if you can use solar power to run electric cars though it could make sense as a range-extension fuel for a PHEV.  The existing transportation fleet could be run longer with ethanol from this source until better vehicles can be built. 
    
    Note that you don't need land- you are using free sunlight.  If you had a coal plant in Illinois with CO2 and free waste night-time electricity, and limited sunlight in the winter, it might make sense to supplement the sun with LED light tuned to match the algae's absorption spectrum.  (No green light!) 
    
    Mr. Thermo punishes you if you try to use the electricity from a coal plant to undo its work to make C to CO2.  But if you are "storing waste electricity with a big dispatchable load that produces ethanol" you may make peace with the gods of thermodyamics and economics. 
    
    FYI, compare this to Solzyme, that is one of the more effiicent algae to oil companies.   I don't think they bother with light at all-- feeding cellulose to the algae. 

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