Biofuels
From Alternative Energy Wiki
Biofuel is defined as solid, liquid or gas fuel derived from relatively recently dead biological material and is distinguished from fossil fuels, which are derived from long dead biological material. Theoretically, biofuels can be produced from any (biological) carbon source; although, the most common sources are photosynthetic plants. Various plants and plant-derived materials are used for biofuel manufacturing. Globally, biofuels are most commonly used to power vehicles, heating homes, and cooking stoves. Biofuel industries are expanding in Europe, Asia and the Americas. Recent technology developed at Los Alamos National Lab even allows for the conversion of pollution into renewable bio fuel.[1] Agrofuels are biofuels which are produced from specific crops, rather than from waste processes such as landfill off-gassing or recycled vegetable oil.[2]
There are two common strategies of producing agrofuels. One is to grow crops high in sugar (sugar cane, sugar beet, and sweet sorghum[3]) or starch (corn/maize), and then use yeast fermentation to produce ethyl alcohol (ethanol). The second is to grow plants that contain high amounts of vegetable oil, such as oil palm, soybean, algae, or jatropha. When these oils are heated, their viscosity is reduced, and they can be burned directly in a diesel engine, or they can be chemically processed to produce fuels such as biodiesel. Wood and its byproducts can also be converted into biofuels such as woodgas, methanol or ethanol fuel[4]. It is also possible to make cellulosic ethanol from non-edible plant parts, but this can be difficult to accomplish economically.
Biofuels are discussed as having significant roles in a variety of international issues, including: mitigation of carbon emissions levels and oil prices, the "food vs fuel" debate, deforestation and soil erosion, impact on water resources, and energy balance and efficiency. The use of biofuels reduces dependence on petroleum and enhances energy security.[5] Also, unlike fossil fuels, which return carbon that was stored beneath the surface for millions of years into the atmosphere, biofuels can produce energy without causing a net increase of atmospheric carbon. This is because as new plants are grown to produce fuel, they remove the same amount of Template:Co2 from the atmosphere as they will release as fuel. Some studies have found that certain crops may produce more harmful greenhouse gases than Template:Co2, indicating that the specific biofuel used is an important factor.
