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This discussion relates to Technology Review's article Biofuels vs. Biomass Electricity.

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  ryuuguu
  

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  05/08/2009 03:11 AM

  air quality

  There is alsothe improved air quality in cities that would result from getting rid of millions IC engines.

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• 
  RickJ
  

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  05/08/2009 03:54 AM

  Biomass to power

  The best way to make power from biomass is indirectly - steam cycle biomass power is perhaps 35% efficient. Burning biomass to make heat frees up natural gas or heating oil which can be burnt in combined cycle gas turbines at up to 60% (LHV) efficiency.

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    arbela
    

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    05/08/2009 06:32 AM

    Re: Biomass to power

    According to the FAO (http://www.fao.org/docrep/T4470E/t4470e0n.htm), high-efficiency boilers in northern Europe reach 60% thermal efficiency.  Biomass gasification, a highly proven technology, can be over 80%.

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      RickJ
      

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      05/09/2009 04:06 AM

      Re: Biomass to power

      It does not take a lot of googling to find wood pellet boilers with 90% efficiency eg www.nef.org.uk/logpile/pellets/boilers.htm - there is no good reason why wood fired combustors should be much less efficient than gas fired systems. Biomass gasification is promising but hardly common - most of the biomass to power projects eg Lockerbie, the biggest in the UK www.eon-uk.com/generation/stevenscroft.aspx use circulating fluidised bed combustors and steam cycles (about 35% efficiency). Gasifiers can produce 80% woood to gas efficiency, but then you have to get the syngas (cannot go in the gas grid) to a big, sophisticated CCGT to realise a 50% plus (HHV) efficiency. The indirect route is a distributed use for a distributed resource.

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  gametheoryman
  

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  05/08/2009 07:33 AM

  results misinterpreted

  The technical results are interesting but the policy conclusions are not. As long as there have been cars, we have always wanted electric vehicles because oil is much more efficient at generating electricity than using it to power our cars from gasoline.
  
  We don't do that because the electric option, which we've always been able to build, is much more expensive than the gasoline option. Even with our large advances in battery technology, though much closer, it still is.
  
  Eventually all electric vehicles will be the way to go, but this is a significant time away. As our electric technologies advance, biofuels are still necessary for the transition to fully electric vehicles through plug-in hybrids.
  
  Also, even if biomass was the preferred fuel for power generation, which is far from clear, we have way more than enough for both purposes.
  
  We could "garden" North American forests, taking primarily fallen timber, for centuries. And, without growing anything new for fuel, our own organic waste plus our agricultural waste is immense.

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    mfolbe
    

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    05/08/2009 11:58 AM

    Re: results misinterpreted

    Why are biofuels necessary?  How is a biofuel/electric hybrid better than a gas/electric hybrid?  I think you made a leap in your logic there.

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    mkogrady
    

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    05/08/2009 12:48 PM

    Re: results misinterpreted

    "we have always wanted electric vehicles because oil is much more efficient at generating electricity than using it to power our cars from gasoline"
    
    Excellent Point and one that the Federal Government who's desire to thwart Global Warming should note. Instead of electric cars per se, the use of Mass transit (ie electric mass transit), combined with smaller E-Vehicles of some type for short or local trips is much more sustainable than giving billions through the Energy Bill and our TARP loans so auto makers can make hybrid cars, electric cars and more fuel efficient IC vehicles. The latter should be left to Free Market to decide, while the big nut to crack should be taken on by the government.
    
    Besides, if we have a crummy harvest one year or more, we can pull coal out of the ground to offset the difference. When harvests become normal again we cut back to Biomass. Finally as Mass Trans and Free Market vehicles become more efficient we reduce overall demand.
    
    Last December (2008) the brow beating the Big Three would have served the nation better IF those elected air-bags had ordered a national mass transit system and permitted the Auto Industry to compete for a portion of it rather than throw a boat load of low interest loans to them so they can move more production off-shore.

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  rhansing
  

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  05/08/2009 11:04 AM

  burning biomass

  I have no problem with using garbage for bio mass, but to use fallen trees and switch grass will turn our farmlands into clay.
  
  This will be creating a more serious problem Remember Easter Island.
  
  I'm Just a kid from Kansas.
  

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  • 
    peteraardvark
    

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    05/08/2009 11:53 AM

    Re: burning biomass

    how about pyrolising the wood or agricultural waste, use the woodgas for power generation and bury the charcoal as biochar.. It will not only sequester c02 (for maybe hundreds of years) and will improve the soil.
    My father who grew up in WWII Europe remembers the Germans using woodgas powered cars and trucks.
    You could also use the tar and other byproducts.

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    • 
      cdlewis
      

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      05/15/2009 09:42 AM

      Re: burning biomass

      Yes,fast pyrolisis is a viable option, it has been successfully been used by the company Dynamotive to manufacture bio-oil for the past several years. In an article by biomassmagazine.com titled thermochemical vs. biochemical it says converting biomass to bio-oil increases the energy yield 12 to 15 times.
      Dynamotive is licensing the technology worldwide as we speak. An excellent cost effective alternative to #2 & #6 petroleum fuel, it is also carbon neutral and sulphur free. Check them out, dynamotive.com

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