Ethanol vs Biodiesel
 

Energy crisis is a major problem in the present world. Therefore, energy production has been the most commonly discussed topic lately. Energy sources can be divided into two types as renewable energy sources and non-renewable energy sources. Renewable energy sources are replenished continuously, and they are natural. For example, wind, water, sunlight and tides are some of the renewable energy sources. Non-renewable energy sources exist only for a certain period, and they cannot be regenerated once they are gone. Coal and petroleum (fossil fuels) are non-renewable energy sources. These take millions of years to form, and once they are used, they cannot be easily regenerated. Scientists are looking for various energy sources, which can be used to replace the non-renewable energy sources we are having. Other than the amount of energy produced from each of these sources, today priority is given to the sources, which cause minimum environmental harm.

Ethanol

Ethanol is a simple alcohol with the molecular formula of C₂H₅OH. It is a clear, colorless liquid with a characteristic odor. Furthermore, ethanol is a flammable liquid. Melting point of ethanol is -114.1 ^oC, and the boiling point is 78.5 ^oC. Ethanol is polar due to the electronegativity difference between the oxygen and hydrogen in the –OH group. In addition, due to –OH group, it has the ability to form hydrogen bonds.

Ethanol is used as a beverage. Ethanol can be easily obtained by the sugar fermentation process using zymase enzyme. This enzyme naturally presents in yeast, so in the anaerobic respiration, yeast can produce ethanol. Other than a beverage, ethanol can be used as an antiseptic to clean surfaces from microorganisms. Ethanol is miscible with water, and it serves as a good solvent. In addition, it is mainly used as a fuel and a fuel additive in vehicles. Ethanol is a renewable fuel made from plants. It does not emit harmful emissions after burning, as petrol does. Further it is biodegradable; therefore, ethanol is environmentally safe fuel alternative. In addition, ethanol can be easily used in petrol engines without much modification.

Biodiesel

Biodiesel is a fuel, which can use instead of petroleum fuel. This is produced from renewable sources. Biodiesel is produced from vegetable oil or animal fat from a chemical process known as transesterification. Biodiesel consists of mono-alkyl esters of long chain fatty acids. Therefore, the transesterification gives these esters as the biodiesel product and glycerin as the by-product. This biodiesel is known as pure biodiesel. Biodiesel also can be mixed with petroleum fuel and can form biodiesel blend. This can be easily used in diesel engines. Since the raw material for producing biodiesel is domestic, production process causes less harm to the environment. Biodiesel itself is environmentally friendly, because it burns cleanly (emit less amount of pollutants upon burning compared to petroleum fuel). It is free from sulfur or aromatic compounds, which cause health problems to humans. Further, biodiesel is simple to use, biodegradable, and nontoxic.