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Algae fuel



Algae fuel is a biofuel from algae.

With the higher prices of oil, there is much interest in algaculture (farming algae) to harvest for making vegetable oil, biodiesel, bioethanol, biomethanol, biobutanol and other biofuels.

The production of biofuels to replace oil and natural gas is in active development, focusing on the use of cheap organic matter (usually cellulose, agricultural and sewage waste) in the efficient production of liquid and gas biofuels which yield high net energy gain. One advantage of many biofuels over most other fuel types is that they are biodegradable, and so relatively harmless to the environment if spilled.[1][2][3]

Additional recommended knowledge

Contents

Fuels

Biodiesel production

Currently most research into efficient algal-oil production is being done in the private sector, but if predictions from small scale production experiments bear out then using algae to produce biodiesel may be the only viable method by which to produce enough automotive fuel to replace current world gasoline usage.[4]

Microalgae have much faster growth-rates than terrestrial crops. The per unit area yield of oil from algae is estimated to be from between 5,000 to 20,000 gallons per acre, per year (4.6 to 18.4 l/m2 per year); this is 7 to 30 times greater than the next best crop, Chinese tallow (699 gallons).[5]

Algae can also grow on marginal lands, such as in desert areas where the groundwater is saline. [6]

The difficulties in efficient biodiesel production from algae lie in finding an algal strain with a high lipid content and fast growth rate that isn't too difficult to harvest, and a cost-effective cultivation system (ie, type of photobioreactor) that is best suited to that strain.

Other obstacle preventing widespread mass production of algae for biofuel production has been the equipment and structures needed to begin growing algae in large quantities. Diversified Energy Corporation have avoided this problem by taking a different approach, and growing the algae in thin walled polyethylene tubing called Algae Biotape, similar to conventional drip irrigation tubing, which can be incorporated into a normal agricultural environment. [7]

Open-pond systems for the most part have been given up for the cultivation of algae with high-oil content.[citation needed] Many believe that a major flaw of the Aquatic Species Program was the decision to focus their efforts exclusively on open-ponds; this makes the entire effort dependent upon the hardiness of the strain chosen, requiring it to be unnecessarily resilient in order to withstand wide swings in temperature and pH, and competition from invasive algae and bacteria. Open systems using a monoculture are also vulnerable to viral infection. The energy that a high-oil strain invests into the production of oil is energy that is not invested into the production of proteins or carbohydrates, usually resulting in the species being less hardy, or having a slower growth rate. Algal species with a lower oil content, not having to divert their energies away from growth, have an easier time in the harsher conditions of an open system.

Some open sewage ponds trial production has been done in Marlborough, New Zealand.[8]

In a closed system (not exposed to open air) there is not the problem of contamination by other organisms blown in by the air. The problem for a closed system is finding a cheap source of sterile carbon dioxide (CO2). Several experimenters have found the CO2 from a smokestack works well for growing algae.[9] [10] Some experts think that algae farming for biofuels will have to be done next to power plants, where they can also help soak up the pollution, to be economical. [11].

A feasibility study using marine microalgae in a photobioreactor is being done by The International Research Consortium on Continental Margins at the International University Bremen.[12]

Research into algae for the mass-production of oil is mainly focused on microalgae; organisms capable of photosynthesis that are less than 2 mm in diameter, including the diatoms and cyanobacteria; as opposed to macroalgae, e.g. seaweed. This preference towards microalgae is due largely to its less complex structure, fast growth rate, and high oil content (for some species). Some commercial interests into large scale algal-cultivation systems are looking to tie in to existing infrastructures, such as coal power plants or sewage treatment facilities. This approach not only provides the raw materials for the system, such as CO2 and nutrients; but it changes those wastes into resources.

In November 8, 2006, Green Star Products has announced that it has signed an agreement with De Beers Fuel Limited of South Africa (but no relation to the diamond company) to build 90 biodiesel reactors with algae as raw material. Each of the biodiesel reactors will be capable of producing 10 million gallons of biodiesel each year for a total production capacity of 900,000,000 gallons per year when operating at full capacity, which is 4 times greater than the entire U.S. output in 2006. Also, GreenFuel Technologies Corporation has delivered a bioreactor to De Beers Fuel. Doubts have been expressed about Green Star's expertise in biodiesel technology. [13] Green Star's president did however answer questions in an online interview with WallSt.net where he claimed that the South African biodiesel production has exceeded the original expectations.[14] People who paid De Beers Fuel for franchises have nothing to show for their investment. [15] GreenFuel has terminated its licensing agreement with De Beers Fuel owing to “nonperformance” and requested that the company remove any reference to the agreement from its website. [16]

Aquaflow Bionomic Corporation announced has produced its first sample of home-grown bio-diesel fuel with algae sourced from local sewerage ponds.

Biobutanol

Main article: Butanol fuel

Butanol can be made entirely with solar energy, from algae (called Solalgal Fuel) or diatoms. It has a couple of mpg better than petroleum gasoline [17]

Methane

Through the use of algaculture grown organisms and cultures, various polymeric materials can be broken down into methane.[18]

SVO

The algal-oil feedstock that is used to produce biodiesel can also be used for fuel directly as "Straight Vegetable Oil", (SVO). While using the oil in this manner does not require the additional energy needed for transesterification, (processing the oil with an alcohol and a catalyst to produce biodiesel), it does require modifications to a normal diesel engine, whereas biodiesel can be run in any modern diesel engine, unmodified, that is designed to use ultra-low sulfur diesel, the new diesel fuel standard for the United States of America that went into effect in the fall of 2006.

Hydrocracking to traditional transport fuels

Vegetable oil can be used as feedstock for an oil refinery where methods like hydrocracking or hydrogenation can be used to transform the vegetable oil into standard fuels like gasoline and diesel. [19]

Biofuel from algae by territory

Canada

  • International Energy, Inc [20]

Oceania

  • New Zealand: Aquaflow Bionomic Corporation (ABC). [21]

USA

There are diverse companies developing biofuels from algae:


See also

Energy Portal

References

  1. ^ Globeco biodegradable bio-diesel
  2. ^ Friends of Ethanol.com biodegradable ethanol
  3. ^ Low Cost Algae Production System Introduced
  4. ^ Biodiesel Production from Algae. Department of Energy Aquatic Species Program, National Renewable Energy Laboratory. Retrieved on 2006-08-29.
  5. ^ Biodiesel. Wikipedia Biodiesel.
  6. ^ http://www.worldwatch.org/node/5391
  7. ^ http://www.environmentalgraffiti.com/?p=237
  8. ^ Biodiesel Made from Algae in Sewerage Ponds. Renewable Energy Access (2006). Retrieved on 2007-01-31.
  9. ^ http://www.csmonitor.com/2006/0111/p01s03-sten.html
  10. ^ http://www.greenfuelonline.com/gf_files/GreenFuel%20Growth%20Rates.pdf
  11. ^ http://www.worldwatch.org/node/5391
  12. ^ Greenhouse Gas Mitigation Project at the International University Bremen. The International Research Consortium on Continental Margins (2006). Retrieved on 2007-01-31.
  13. ^ Biofuel from algae startup on shaky ground. Renewable Energy Access (2006). Retrieved on 2007-05-09.
  14. ^ "Green Star Products, WallSt.net exclusive audio". WallSt.net (2007). Retrieved on 2007-06-04.
  15. ^ http://www.engineeringnews.co.za/article.php?a_id=110645
  16. ^ http://www.engineeringnews.co.za/article.php?a_id=110455
  17. ^ http://www.fossilfreedom.com
  18. ^ Methane production. FAO, Agriculture Department. Retrieved on 2006-08-29.
  19. ^ http://www.greencarcongress.com/2006/12/conocophillips_.html
  20. ^ http://www.internationalenergyinc.com
  21. ^ http://www.aquaflowgroup.com
  22. ^ http://www.aurorabiofuels.com
  23. ^ http://www.globalgreensolutionsinc.com
  24. ^ http://www.imperiumrenewables.com , http://www.news.com/8301-10784_3-9727005-7.html
  25. ^ Live Fuels, Inc.
  26. ^ http://www.petrosuninc.com
  27. ^ http://www.news.com/8301-11128_3-9832304-54.html?tag=nefd.top
  28. ^ http://www.solixbiofuels.com
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Algae_fuel". A list of authors is available in Wikipedia.
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