Algae Biofuels

Algae biofuels are alternatives to fossil fuels. These carbon neutral fuels are cheap and easy to use. In a world of rising oil prices and increasing concern over environmental pollution, algae biofuels are gaining a lot of momentum.

Algae are unique species that are neither classified as flora nor fauna. These organisms use photosynthesis to transform atmospheric carbon dioxide and sunlight into energy. There are more than 30,000 known species of algae. They reproduce tremendously fast and can effectively double their weight several times a day. Algae can grow in salt water, freshwater or even brackish water, in sea or in ponds, and on land not suitable for food production.

As part of the photosynthetic process, the absorbed carbon dioxide and sunlight are used to produce sugars and lipids. Excess of these lipids are stored as fat inside the algae cells. This fat can be used to produce vegetable oil, which is further distilled to produce many other forms of fuel. Different species of algae can be used to produce different varieties of oils. Algae can generate 15 times more oil per acre than other plants used for biofuels, such as corn and switch grass.

There are many small companies producing algae biofuels around the world. Some of them are GreenFuel Technologies, Solazyme, Blue Marble Energy, Inventure Chemical, Solena, Live Fules, Solix Biofuels, Aurora Biofuels, Aquaflow Binomics, Petro Sun and Bionavitas. In India, a Kerala based company; Enery Microlgae is producing algae fuel commercially. Last year, in a unique experiment, jet algae fuel was used to power a two-hour test flight of a Boeing 737-800 of the Continental Airlines. These fuels are absolutely carbon neutral, which simply means that the amount of carbon dioxide absorbed by the algae is equivalent to the amount of carbon dioxide produced while burning the fuels. Hence, they do not increase the amount of carbon dioxide in the atmosphere, in turn slowing global warming.

Scientific interest in producing fuel from algae has been around since the 1950s. Most previous and current research on algae biofuels has used the open pond system. In this system, the alga is allowed to grow in open water bodies with just the naturally occurring inputs of atmospheric carbon dioxide and sunlight. This approach results in a rather low yield of oil – about 1 percent by weight of the algae and also prone to contamination by unwanted species. As opposed to this, scientists are now proposing the helix photo bioreactor, which is a closed indoor system. This however increases the cost of production and moves away from the use of natural sunlight. Some other scientists prefer the ‘Vertigo’ technique, in which the algae crop is vertically oriented and controlled.

The greatest benefit of algae biofuels over other alternative fuels comes from the fact that they can be used in cars and airplanes without any modifications to the currents design of the machines.

However, only a few studies are publicly available on the economic viability of algae biofuels. It is estimated that algae oil would only be competitive at an oil price of $800 per barrel. The cost of production varies according to the specie of algae used, the system of production, the method of harvesting and even the amount of sugars and carbon dioxide fed to the crop. Some entities have reported capital costs as low as $10k/acre, while others have shown costs approaching $300k/acre.

The problems in accurately determining the economic viability are accentuated by the fact that there are no large-scale commercial algae biofuels production systems with which to develop and substantiate data. The companies that are developing new technologies and architectures are very protective of their detailed financial data.

One acre of algae can produce enough oil to make 5,000 gallons of biodiesel in a year. It is estimated that an area equal to half that of the state of Mexico, would be enough to meet the energy demands of the entire USA. The potential of these biofuels cannot be overlooked. It seems too good to be true. For the time being, scum powered cities do seem to be overpowering my imagination. Algae biofuels might prove to be the clean and scalable energy solution that we have been looking forward to for so long.

Mansi Baranwal

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