Alternative Fuels

30/04/2007

With the recent Brazilian efforts so that etanol is changedded into one “commodity” international, the debate was lit on the benefits of the biocombustíveis versus fósseis fuels, to the oil base. The diverse arguments, against and the favor, leave clearly that the solution of the question is far from being easy.

Comparative degree between fuels
This also is the conclusion of a study that finishes to be published by two Norwegian scientists. Karl Hoyer and Erling Holden had compared the ambient costs of diverse fuels for automobiles, since the gasoline and the oil diesel, until that they are only technological promises, still far from the viabilização, as hydrogen.
The result is one “ranking” that it can seem logical to the first sight: the gasoline and diesel, as it would be of if waiting, are in the last ranks. But zebras in the classification has some hidden supreendentes.
The comparative degree enters alternative fuels for vehicles was made taking in consideration the energy expenses and the emission of pollutants in the stages of production, industrialization and consumption of some fuels. The use of energy, the emission of gases .causing of the effect greenhouse and the emission of pollutants had been computed local and regionally.
Gasoline , diesel and natural gas and alternative fuel sources had been compared, as etanol, methanol, biocombustíveis and hydrogen.
Of low to top in the classification, then after the vehicles the gasoline they come the vehicles bicombustible that consume gasoline and natural gas. “Any alternative fuel that we consider is better of what the cars who we use today, “ say the researchers.
The great champion in terms of ambient profits is the hydrogen, extracted of methanol and generating energy by means of cells the fuel. This is, however, an option still far from the economic viabilização and that, exactly of the point of view strict technician, still possesss problems to be decided.

Ambient costs
The researchers had mounted its ranking attributing to one weight of 1 the 16 for each one of the considered item: use of energy, carbon emissions and pollution with nitrogenados oxides. The weights had been attributed collecting the total data since the extration or production of the fuel until its burning in the engine of the car - of the well to the exhaust pipe, as the researchers say.
When the weights of each stage are added, the result are a note that is equivalent to all the energy chain of each fuel, in each one of the three item. For example, in the case of hydrogen, they had been considered the extration of the natural gas in the well, its processing for extration of liquefeito hydrogen, the storage of hydrogen and its use in a cell the fuel equipping an automobile.
The energy chain that possesss the lesser general addition was best placed in ranking, since the addition of its impacts in the considered item was the possible minor. The energy chains with the biggest general addition are considered the those potentially most harmful ones to the half-environment.

Better combustible
It does not leave of to be interesting the fact of that the hydrogen, exactly generating only water as by-product in its use in the cell the fuel, either also a “fossil alternative” - after all, the natural gas is practically “brother-twin” of the oil, being also a finite resource.
It is for that the researchers so are interested in extracting hydrogen of other sources - of the water, more specifically (only for the results most recent, sees Super molecule is true plant of force, generating hydrogen with solar energy e Biocélula the fuel generates energy of hydrogen in surrounding air).
The same natural gas, for another side, when burnt directly in the engine, only is behind the gasoline and of diesel, in terms of efficiency, energy expense and pollution.
Another disillusionment was biometanol - the extracted methanol of sources you renewed. Exactly when used in cells the fuel, as hydrogen, it it is in the last ranks, with great ambient impacts.
“He must be emphasized that no energy chain individually has the best rank in all the categories of impact, “the researchers say. “It always has some type of involved commitment. In such a way, it does not have obvious winners; only good and bad counterparts between the different categories of impact. “

Route of the biocombustíveis
It is not to toa that a consensus does not exist currently on what would be the option most sustainable or more ambiently correct when the subject the biocombustíveis are the fuels - exactly. What it has been seen they are partial arguments, based in partial research, that takes in account only partial aspects. The result is that they finish if sobressaindo the arguments politicians. As an unequivocal winner does not exist, he can also be considered routes to follow in the attempt of if reaching a auto-sustainable system of transports. The route of the efficiency can be followed - improving the energy income of each fuel, - the route of the substitution and the route of the reduction of the consumption. Exactly there, however, it has problems. “Each [route] has its defenders,” says the scientists, “but, in the reality, it has enormous zones leached ashes between them.”


VOCABULÁRIO:

Commodity – Conveniência, mercadoria, artigos de primeira necessidade, moeda neutra, bolsa de mercadorias, mercado de utilidades.
Published – Divulgador, editor, publicador.
Hidden- esconder, encobrir, esconder-se, ocultar-se.
Vehicles- veículo, carro.
Profits- proveito, lucro, benefício, ganho.
Weights- peso, gravidade, ponderação, consideração, importância, conseqüência.
Disillusionment- desilusão, desengano, desenganar, desiludir.
Counterparts- contraparte, reprodução, translado.
Currently – comum, corrente.




PERGUNTAS:

1- O QUE SERIA COMMODITY INTERNACIONAL?
2- QUAL É A DIFERENÇA ENTRE BIOCOMBUSTIVEIS E COMBUSTÍVEIS FOSSEIS?
3- QUAL O INTERESSE DOS PESQUISADORES EM EXTRAIR HIDROGÊNIO DE OUTRAS FONTES?
4- O QUE SE ENTENDE POR ROTA DOS COMBUSTÍVEIS?
5- QUAIS SÃO OS RECURSOS FINITOS?

Grupo:

Drielly nº 2
Jéssica nº 18
Joice nº 19
Larissa nº 24