What is biodiesel?
Biodiesel is the name of a clean burning alternative fuel, produced from domestic, renewable resources. Biodiesel contains no petroleum, but it can be blended at any level with petroleum diesel to create a biodiesel blend. It can be used in compression-ignition (diesel) engines with little or no modifications. Biodiesel is simple to use, biodegradable, nontoxic, and essentially free of sulfur and aromatics.
Biodiesel can also be used as a heating fuel in domestic and commercial boilers. Existing oil boilers may require conversion to run on biodiesel, but the conversion process is believed to be relatively simple.
How is biodiesel made?
Biodiesel is made through a chemical process called transesterification whereby the glycerin is separated from the fat or vegetable oil. The process leaves behind two products -- methyl esters (the chemical name for biodiesel) and glycerin (a valuable byproduct usually sold to be used in soaps and other products).
The use of biodiesel in cars
Biodiesel can be used in unmodified diesel-engined vehicles. It is thus distinguished from the straight vegetable oils or waste vegetable oils used as fuels in some diesel vehicles.
Biodiesel is biodegradable and non-toxic, and typically produces about 60% less net carbon dioxide emissions than petroleum-based diesel, as it is itself produced from atmospheric carbon dioxide via photosynthesis in plants.
Biodiesel is a better solvent than standard diesel, it 'cleans' the engine, removing deposits in the fuel lines, and this may cause blockages in the fuel injectors. For this reason, car manufacturers recommend that the fuel filter is changed a few months after switching to biodiesel.
Fuel stations and Biodiesel.
Biodiesel can be distributed using today's infrastructure, and its use and production are increasing rapidly. Fuel stations are beginning to make biodiesel available to consumers, and a growing number of transport fleets use it as an additive in their fuel. Biodiesel is generally more expensive to purchase than petroleum diesel but this differential may diminish due to economies of scale, the rising cost of petroleum and government tax subsidies. In Germany, biodiesel is generally cheaper than normal diesel at gas stations that sell both products. Biodiesel is available at many gas stations in Europe.
Transitioning fully to biofuels could require immense tracts of land if traditional crops are used. The problem is especially severe for nations with large economies, since energy consumption scales with economic output. If using only traditional plants, most such nations do not have sufficient arable land to produce biofuel for the nation's vehicles. Nations with smaller economies (hence less energy consumption) and more arable land may be in better situations, although many regions cannot afford to divert land away from food production.
Unused desert land,which receives high solar radiation, could be most effective for growing certain species of algae, and the algae could utilize farm waste and excess CO2 from factories to help speed the growth of the algae. In tropical regions, such as Malaysia and Indonesia, oil palm is being planted at a rapid pace to supply growing biodiesel demand in Europe and other markets. The direct source of the energy content of biodiesel is solar energy captured by plants during photosynthesis.
- Biodiesel reduces emissions of carbon monoxide (CO) by approximately 50% and carbon dioxide by 78%
- Biodiesel contains fewer aromatic hydrocarbons: benzofluoranthene: 56% reduction; Benzopyrenes: 71% reduction
- Biodiesel is biodegradable and non-toxic, it is less toxic than table salt and biodegrades as quickly as sugar.
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