Ethanol

Today, renewable energy sources are commonly used to replace fossil fuels due to the lacking of oil, gas, etc. An alternative energy source is ethanol (C2H5OH). It is an alcohol fuel manufactured by fermentation and distillation of crops that are high with starch and sugar, such as grains, sugarcane (most commonly used), corn, and fruit. Other names for ethanol are ethyl alcohol, drinking alcohol, and grain alcohol. It can also be made from trees, grasses, woods, and plant waste. It is a colourless, flammable liquid that is categorized under bio-fuel. Brazil is the largest suppler and consumer of ethanol in the world. Ethanol functions in the same way as gasoline. In vehicles, it is blended with conventional gasoline to make gasohol (90% gasoline and 10% ethanol). It is clean-burning and consists of high energy.

The use of ethanol has brought lots of advantages to the society. A benefit of it is that it is renewable. It has a higher energy density than some other alternative fuels. This means that less volume is required to travel the same distance. Secondly, ethanol decreases the emissions of the toxic ozone-forming compounds. For example, tailpipe emission of carbon monoxide from vehicles can be reduced by preferring ethanol over gasoline. Since ethanol is made from plants, it improves the agricultural economies by providing a stable market for a certain crops.

Although ethanol has positive impacts on our countries, few disadvantages are found in researches. First of all, the cost of ethanol is quite high. In the year of 1987, it cost 2.5 to 3.75 times as much as gasoline. As it is stated above, ethanol has a high energy density, so it needs 1.5 times as much as gasoline to go the same distance. Also, large amount of land is required to crops and the conversion of plants to ethanol is very inefficient because of the large water contents in plants. Burning it does not produce toxic substances, but it may increase the emission of pollutants. Utilizing