Biodiesel, Necessary or Unnecessary.

                Today Biodiesel has become one of the hot topics in the field of fuel for transportation. It is noticeable that a large number of countries are stepping forward to implement the biodiesel manufacturing. Due to the rise of the petroleum diesel prices the demand for the biodiesel is increasing. The article that is to be discussed on is by the Energy Information Administration of the United States.

                The Energy Information Administration claims about a number of benefits about the implementation of the Biodiesel. In the United States the major source for the biodiesel production are the soya bean oil and yellow grease. There are two kinds of way in which the biodiesel can be used. The first one is blending with normal petroleum diesel and the other one is using the bio diesel as a primary fuel.

                The biodiesel has a higher cetane number compared to petroleum diesel. This helps it autoignite faster when compared to the normal diesel. The cetane number of biodiesel has an average of 50.9 whereas the cetane number of normal diesel is somewhere in between 30 and 45. Another great property of biodiesel is the lack of sulphur. This property gives biodiesel a better lubricate than the petroleum diesel. Biodiesel also have some performance disadvantages. The performance of biodiesel in cold weather conditions is much worse than the normal petroleum diesel. The cloud point and the pour point of the biodiesel are higher when compared to the petroleum diesel.

                Another main disadvantage is that the biodiesel tends to reduce the fuel economy. Energy efficiency and the volumetric efficiency of biodiesel is low when compared to the petroleum diesel. The energy content per gallon of biodiesel is 11% lower than that of petroleum diesel and using the biodiesel is expected to reduce the volumetric efficiency by 2.2%. About 11% of the weight of the biodiesel is oxygen. The presence of oxygen causes the nitrogen oxide emissions which will affect the ozone layer at a higher level when compared to the carbon monoxide by the petroleum diesel.

                Biodiesel can be produced by various processes. Among all the main way for the production of the bio fuel is from the soya bean oil. From the data acquired from the past few years the price of the soya bean is increasing every year. This exponential increase in the price soya bean has caused an increase in the price of the biodiesel. This price hike made biodiesel expensive to use than the normal petroleum diesel. However, in the United States the government has given incentives to support the expansion of biodiesel production.

                Biodiesel made from the yellow grease is more cost – competitive with the petroleum diesel than is the biodiesel from the soya bean oil. But the available supply of the yellow grease will limit its use for biodiesel production by 100 million gallons per year or less. Unless the soya bean oil prices decline dramatically, it does not appear that biodiesel can be produced in large quantities at a cost that is competitive with petroleum diesel.

Evaluation

                Although many advantages of biodiesel is mentioned in the article above, the disadvantages it shows is equally high too. The first one is the lack of performance is the cold weather conditions. The U.S and China are cold countries and since the majority of the vehicle users in the world comes from here. This makes it difficult to implement the use of biodiesel in these two countries.

                The article also mention that the biodiesel also tend to decrease the fuel economy. Since the energy efficiency and the volumetric efficiency of biodiesel is low when compared to the petroleum diesel, the users are reluctant to change the fuel from petroleum diesel to the biodiesel. Another major issue is the pollution of the atmosphere. While the operation, vehicles using biodiesel causes nitrogen oxide emissions which is much more dangerous than the carbon monoxide.

                All these disadvantages are equally high than that of the normal diesel. This makes it necessary to think twice about implementing the biodiesel to replace the petroleum diesel.

Reference:

Energy Information Administration (US).  “Biodiesel Performance, Costs and Use.” Retrieved on March 10, 2009 from http://www.eia.doe.gov/oiaf/analysispaper/biodiesel/

Vocabulary Reference

Cetane number: A measure of the ignition quality of a diesel engine fuel by comparison with various mixtures in which the alpha form of methylnaphthalene is given a standard value of 0 and cetane is given a standard value of 100.

Could Point: The temperature at which a sample of the fuel starts to appear cloudy

Pour Point: The temperature below which the fuel will not flow.

Energy Efficiency: The percentage of the fuel’s thermal energy that is delivered as engine output.

Volumetric Efficiency: Mile travelled per gallon of fuel.