(translated by Sean R. Stevens)
The green-house effect is currently one the most talked about themes in the public, political, and scientific realms. Attempts are currently being made to reduce carbon dioxide production by the burning of fossil fuels, such as oil and natural gas, in order to reduce the human impact on global warming. Alternative energy sources are being intensively researched: solar power, fuel cells, wind power, and hydropower point to possible ways of totally replacing fossil fuels one day. One alternative particularly favored and discussed by the public and politicians is biofuel, especially bioethanol. The proportion of bio ethanol used in gasoline is currently being increased in the EU yearly (1.2% in 2007, to 3.6% in 2010).
The fermentation of sugary fruits into alcohol (=ethanol) was already described by the ancient Egyptians 5000 years ago. In the bible, alcohol is mentioned in the first book of Moses (Gen. 9, 18-29). Alcohol containing beverages are produced in the same way even today. Alternatively, the industrial production of alcohol, used in large amounts by the chemical industry as solvent and in medicine as a disinfectant, is carried out by the addition of water (hydration) to ethylene, a chemical derived from oil (diagram to the right, click in order to enlarge). As this reaction is reversible, ethylene, important in the production of plastics (Polyethylene, Polypropylene, Polystryrene), can be possibly produced from sugar. For countries such as Brazil, which has no natural sources of oil, and, due to financial reasons, cannot import the required amounts of oil, the utilization of sugar cane and other biomass that contains starches as sugar sources, offers a way of plastic production independent of oil.
Ethanol can also be used as automotive fuel, a usage that, at least in Brazil, is already well established. There, gasoline typically contains 25% ethanol; in the meantime, automobiles that can burn ever-increasing amounts of ethanol are being developed. Although carbon dioxide being held responsible for global warming is produced by the burning of ethanol, just as with gasoline, the fact that bio ethanol comes from plants - regenerative resources that use carbon dioxide taken from the air for growth - suggests that its usage does not increase the production of green-house gases, and is therefore climactically neutral.
> > > Part 2: Bio ethanol - a climate friendly source of energy?
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