Hello, as always, I'm here to put some people out of their misery. I am a compassionate person, so I do this for free. Let's roll:
1. sugar cane does not grow where rainforests grow. In Brazil, Sao Paulo State is where most sugar cane is grown.
Now check where that State is located, then check a map of where the tropical rainforest is:
The forest:
Sao Paulo State:
Enough said.
2. In most modern sugar cane operations, 50% of the residue is left in the field, the other residue is used to power the cane pressing and sap boiling operations. These residues deliver electricity to the Brazilian grid. So they are a bioenergy source in themselves.
3. This is no different than the traditional operations where the same ratio was used: 50% residue-to-field versus 50% residue-to-fodder. These cane fields have high productivities for 100, 200, even 300 years.
The EROEI of Brazilian sugar cane ethanol varies between 6 and 10.
4. About the rainforests: one can think of an ethanol future based on cassava, a crop which yields almost as much as sugar cane. Cassava *explicitly* cannot stand rainforest zones; it's agro-ecological zone is *explicitly* located outside rainforests.
So please let's stop this continuous desinformation once and for all.