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Why Algae to biofuel?

Algae have a number of advantages over other land based crops when considering the algae to biofuel equation.
algae ethanol

Why Algae To Biofuel? Here are just a few reasons:

  • Much greater productivity than their terrestrial cousins
  • Non-food resource
  • Use otherwise non-productive land
  • Algae can utilize saline (Salt) water
  • Can utilize waste CO2streams
  • Algae can be used in conjunction with waste water treatment
  • An algal biorefinery could produce oils, protein, and carbohydrates
  • Algal cultivation can be 50x more productive than traditional crops
  • Potential for culture in areas not used for crop production 
    • Desert land
    • Ocean

Co-products and By-Products Are Equally Valuable Commodities

algae to biofuel
  • Co-products from the algae, (omega-3 oils) depending on strain, can bring as much as $3,000/ton USD
  • Animal and Fish Feeds are currently selling for $2000/ton USD

Cost Considerations

  • Can use wild algae for ethanol production = free algae inputs
  • Raceway ponds are economical to build.
  • Supporting mechanical infrastructure costs can be offset with solar energy inputs.

Wild algae

  • Have to be fast growers to survive in nature
  • Algae generally contain <10% oil (lipid)
  • Generally contain high carbohydrate >50%
  • Can be grown in open raceways without fear of contamination

Using Raceway Ponds

algae to biofuel
  • Raceway ponds are low cost installations ($75 000/ha)
  • Ponds consume very little power (10 kW/ha)
  • Starch to ethanol conversion plant is relatively expensive and energy intensive (distillation)

High oil producing algae

  • Are slower growers than wild algae – double every 2-3 days
  • Can be selected for maximum oil content – 50% not unusual
  • Need to be grown in protected environment – typically PBR’s
  • Most algae oil can be used for biodiesel production

Algae To Biofuel With Photo bioreactors (PBR’s)

algae to biofuel
  • Allow tight control of growing environment
  • Optimize light usage
  • Are capital intensive
  • Are generally power intensive (300 kW/ha?)

Why algae to biofuel? Put simply, lipids in algae oil can be made into biodiesel, while the carbohydrates can be converted to ethanol. Algae are the optimal source for second generation bioethanol due to the fact that they are high in carbohydrates/polysaccharides and thin cellulose walls.

Currently bioethanol is produced by fermenting sugars, which in the case of corn are derived from hydrolyzing starch. Algae species starch contents over 50 percent have been reported. With new technologies, cellulose and hemicellulose can be hydrolyzed to sugars , creating the possibility of converting an even larger part of algal dry matter to ethanol.

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The Algae Revolution Has Begun

algae biofuels

David, just read through your book on algal biodiesel. Nice layout, easy to read with emphasis on building from local materials and good optimism. We may use some of these ideas for our engineering senior design course this year on biofuels production. Thanks..

Terry Walker
Professor of Biosystems Engineering
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Click Here to Leave a Comment Below 4 comments
Steve Teter - July 26, 2012

Producing biodeisel with alge is like making manmade diamonds. It takes mother nature years to complete the same process. What man has done is to accelarate the process to where it commercialy practical.

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fernando encluna - October 13, 2012

in the Philippines, there are seaweeds, I’m not sure if the algae you’re talking about could be it. some are eaten since it’s not only nutritious, but delicious as well. Oriental people living near the sea, seaweeds are part of their diet. I just hope that the algae, used as feedstock for bioethanol or biodiesel are not seaweeds that are edible. the Chinese, Japanese, Koreans, Vietnamese, Filipinos are sure eaters of seaweeds.

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    admin - October 14, 2012

    Not all seaweeds are able to be used for biofuels. Only certain species. Even then, I imagine the market for edible seaweed, pound of pound, is more cost effective to use as food. It takes a lot of seaweed to produce fuel, whereas the entire plant can be used as food. There is no doubt as well, that certain Asian edible seaweeds are making their way into American and Western markets as well. I would expect to see more because as you say, it is delicious. This is a market which is going to expand in the near future. My son, given the choice between seaweed snacks and chocolate, chooses seaweed every time. It’s that good.

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