This is a really nice read. I was having a question a first but I found the answer in the body of the post. Wouldn't it compete with human for food and hence increasing the price. But I've gotten the answer.

One thing I think will work tho. What if instead of using the food part of the plant for the production of bioethanol, we can make use of the stem, the leaves, the roots... They should contain some percentage of CHO which will be all that is needed for the fermentation. Maybe not as efficient as that of the food part but a good alternative.