Biofuels are an alternative fuel source derived from living or recently living organisms. The purpose of biofuels is to replace fossil fuels for energy and transportation. Biofuels come in several forms as the result of different processes, such as producing ethanol from corn or using algae to produce fuel.
Fossil Fuels Vs. Biofuels
Fossil fuels, such as coal, oil and natural gas, come from organic matter, just as biofuels do. However, fossil fuels form from decaying organic matter after millions of years of heat and pressure underground. Biofuels, on the other hand, can be created from organisms that are still alive or have died only recently.
Types of Biofuel
Biofuels can be produced several ways. Ethanol is the most commonly used biofuel in the United States -- the U.S. used almost 13 billion barrels of ethanol in 2012. Ethanol can be made from crops such as corn and sugar cane, and is mixed with gasoline to be fuel for vehicles. Cellulosic biofuel, a type of ethanol, comes from plant matter. Algal fuels use algae to produce fuel from nutrients, water, light and carbon dioxide.
Biofuel and the Environment
Biofuels have some environmental benefits. For example, biofuels derived from plants are carbon-neutral, because they take in carbon over their lifespan and then emit it when they are burned. However, producing and transporting ethanol is energy and carbon-intensive, so that more carbon may be released and more energy expended in making it than would have been done in creating and using a comparable amount of fossil fuels.
So far, no biofuel has enough widespread use to replace fossil fuels. Ethanol is the most commonly used biofuel, and it relies on large corn subsidies to reduce the costs of production. Similarly, other fuels like algae biodiesel have problems with scalability, so it is hard to produce a lot of it cheaply. Furthermore, the Environmental Protection Agency mandates that a certain amount of renewable fuel be produced and added to domestic gasoline. The Renewable Fuel Standard for 2013 requires, for example, producing 6 million barrels of cellulosic biofuel. So much of the current U.S. use of biofuels is motivated simply by legal compliance.
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