Ecoutes tu affirmes qu'on fait de l'éthanol au Brésil à partir de canne à sucre et qu'on déforeste pour la cultiver, je te réponds que tu ne peux pas cultiver dans la canne à sucre là où il y a de la forêt et que la production d'éthanol ne se fait pas avec de la canne à sucre directement mais qu'elle est faite uniquement à partir des déchets de l'industrie du sucre. C'est pas un point de détail que je remets en cause c'est l'ensemble de ton argumentation.
Tape ethanol brazil molasse sur google ou sur google scholar et tu as quantité de documents qui t'expliques le système, je te copie colle un exemple:
Ce qui pousse la production de canne à sucre au Brésil c'est d'abord l'abandon des barrières douanières qui protégeait la betterave sucrière... La production d'éthanol c'est juste du collatéral...Admirers of the Brazilian experiment love to point out how cheap Brazilian ethanol is, and it is cheap, under a dollar a gallon to produce. People assume that such a figure is attributable to some combination of the inherent superiority of the sugarcane feedstock, Brazil’s relatively low labor costs, and high efficiency of Brazilian plants, and indeed the second and third factors are significant. The first is not, however, and the real reason that Brazilian ethanol is so cheap is that it isn’t manufactured with sugar. If it were, the industry would have probably failed.
Why Sugar Ain’t It
But that can’t be true, can it? Everybody says that it’s the sugar, so it must be.
But it’s not. Can sugar is not used in Brazil to produce ethanol except for use in potable spirits.
Instead the distillers use a cane byproduct, namely molasses which mostly goes into animal feed otherwise. The cane sugar continues to sell into its traditional markets, foods and confections and booze, and what had been a low value co-product suddenly becomes valuable.
If, on the other hand, you try to divert the whole sugar crop into ethanol production, then the economics don’t look so good anymore. Making ethanol from cane juice, which is the prinicipal product of the sugar refinery, is actually more expensive than making it out of corn the North American way. More total energy is required, and you also have to deal with the fact that ethanol distilleries are necessarily idle much of the year due to the near impossibility of storing the cut cane for any length of time.
Both the USDA and the government of the Philippines have done lengthy and rigorous studies on the economics of ethanol produced sugar cane, and both have come to the same conclusion, that there is only a good business case when molasses alone is utilized.
The implications of this are pretty grim. At the point where traditional markets for cane sugar are saturated the side business in ethanol starts to founder.
Après sur le potentiel des biocarburants, l'uranium, le charbon, le pétrole et le gaz naturel qui sont consommés en France ne sont pas produit sur le territoire français, pourquoi voudrais-tu que les biocarburants consommés en France soient obligatoirement produits sur le territoire national?
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Envoyé par Tilleul 