Biodiesel fuel is a renewable substitute for diesel produced from fossil fuels. Various natural oils, fats and greases can be converted into biodiesel, which can help drastically reduce the levels of greenhouse gases. Not only does biodiesel fuel produce cleaner emissions, but its very production removes carbon from the air, thus lowering pollution. Several species of algae have been studied for their ability to produce natural oils that can be converted to natural fuel.
Types of Algae
Microalgae are very primitive forms of plants. By the same process of photosynthesis plants use, microalgae converts carbon in the environment, and stores that energy in lipids. The microalgae most often studied for biodiesel fuel production fall into two categories. Blue-green algae are very close in structure to bacteria. There are about 2,000 reported species of this nitrogen-fixing algae. Golden algae is closer in structure to diatoms. Most of the 1,000 species described are found in fresh water.
For more than 20 years, researchers have been studying algae for use in biodiesel fuel production. In the United States, the Carter Administration established the U.S. Department of Energy in 1978. In response to the energy crisis of the 1970s, the Department of Energy began studying alternative fuels, such as those produced by algae. The Aquatic Species Program was designed to specifically study algae and other aquatic life for biodiesel fuel production. Although the program was closed in 1995 because of funding cuts, research continues in universities and other government agencies around the world.
According to the National Renewable Energy Lab's report on the Aquatic Species Program, "Put quite simply, microalgae are remarkable and efficient biological factories capable of taking a waste (zero-energy) form of carbon (CO2) and converting it into a high density liquid form of energy (natural oil)." (see Reference 1, p.3) Microalgae can produce 10,000 gallons of fuel per acre per year compared to only 70 gallons from soybean and 230 gallons from corn.
One of the greatest advantages for using algae to produce fuel is that algae can grow in any number of climates and environments. While traditional crops, such as soy and corn, must be grown on fertile agricultural land, algae can thrive in ponds, the ocean and even the desert. Researchers are currently developing new varieties of algae to optimize natural oil production. As John Morgan explains on Purdue University's News website, "Algae now store some of their carbon as lipids, but not enough to be useful in producing biodiesel. We need to genetically engineer them to increase the amount of lipids they accumulate."
With signs of fuel shortages and the effects of global warming becoming more evident, scientists continue to search for cleaner renewable fuel sources. Algae may very well be the fuel of the future. Using algae to produce fuel started as early as the 1950s, when researchers studied algae's methane gas production. Today, algae is becoming an option for biodiesel fuel production.