beaker pouring green ooze into a test tube

Biofuels from Algae

Algae fuel, also called algal fuel, oilgae, algaeoleum or third-generation biofuel may be the green fuel of the future. Algaes range from single-celled diatoms and pond scums to large seaweeds — they are the world's most abundant form of plant life and, via photosynthesis, are extremely efficient at using sunlight and carbon dioxide from the air to make organic material such as sugars, proteins and, under the right conditions, oils.

The photo-bioreactor is the main equipment used to harvest algae. Photo-bioreactors can be set up to be continually harvested, or by harvesting a batch at a time. A batch photo-bioreactor is set up with nutrients and algal seed, and allowed to grow until the batch is harvested. A continuous photo-bioreactor is harvested, either continually, as daily, or more frequently.

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Some of the factors effecting algae harvest:

  • Sunlight - too much direct sunlight can kill them
  • Temperature must be held steady
  • Overcrowding of algae inhibit their growth
  • The waste oxygen produced by them should be continually removed from the water for healthy growth
  • Open algal ponds are subject to evaporation and rainfall - causing salinity and pH imbalances
  • Local species of algae may overgrow the desired strain.

Extracting Oil from Algae and Absorbing Carbon

The process of extracting oil from algae is basically the same as other biofuel technology. However, algae do not require prime agricultural land and has a potential yield that far exceeds other renewable sources. Algae can be grown on waste land in plastic tanks called bioreactors, with little more than sun, heat and water — and the water can be salty, which leaves freshwater for food crops.

Even better, algae could efficiently absorb the carbon being put out by fossil fuel power plants, producing a biofuel that is close to being carbon neutral. Algae consume carbon dioxide to grow. Through photosynthesis, algae pull carbon dioxide from the air, replacing it with oxygen. For this reason, algae based biofuel manufacturers are building biofuel units close to energy manufacturing plants that produce lots of carbon dioxide. In other words, by taking in the waste CO2 from the burning of fuel and using that mixed with the sun to produce algae bioFuel you are in effect closing the CO2 loop.

Fuel is burned for electricity, CO2 is fed into algae which are harvested for biofuels that are burned and emit less CO2 than fossil fuels. If there is enough bioFuel created to be burned for electricity then the algae reactors could in turn be feeding themselves. However, large CO2 emitters like coal and oil might still be the most productive CO2 emitters to yield the highest algae output. There are plenty of power plants with spewing smoke stacks across the globe to feed the algae that can be converted into biofuels.

Two companies are ready for large scale production of algae into bioFuel. Green Fuel Technologieshas begun construction on their plant for a Closed Water Algae bioreactors that will be feed from the smoke stacks of a power plant. While PetroSun has announced that their farm of algae ponds will be going commercial on April 1st (…Hope that is not a joke).

Like BioDiesel and Ethanol it is unlikely that you will be seeing Algae BioFuels at your local gas station any time soon. As it is just ramping up production, and while it does not have the government hand-outs that ethanol has enjoyed and Coal-to-Fuel is trying to acquire, we hope that it can find the strong support in sales that it needs to spread into all areas of the country. With locations like China and their industrial CO2 waste, a system like Closed Water Algae to BioFuel might really help to clean up the air enough to make it breathable again

The oil derived from the pressed algae is wonderfully pure, and can be purposed to cosmetological and food uses as well as biodiesel; the pressed algae becomes protein or spirulina cake, suitable for feed and food.

Many biotech companies around the world are working on using algae to produce ethanol or biodiesels that could replace traditional transport fuels while avoiding the problems raised by traditional crop-based biofuels, such as displacing food crops.

Unfortunately, the process of getting the oil out of the algae is difficult. These are the steps as listed in Colorado State University's research department: first you have to select the right species and then you need to develop an optimal photo-biological formula for each species, and build a cost-effective photo bioreactor that can precisely deliver the formula to each individual algae cell. To be effective this needs to be able to be done no matter the size or the location of the facility. Picking the right species is a difficult task since most algae does not produce the right amount of oil per cell and the ones that do, only do so under certain conditions. The challenge comes from finding a species of algae that can produce the maximum amount of oil per cell and be able to do this under a variety of conditions.

Biofuels from Algae copyright 2011