Does biofuel production use water efficiently?

Answer 1

Excellent question.

No; it takes, I think, about 100 tons of water to make 1 ton of grain; and the grain then needs to be converted to ethanol.

The US ethanol industry serves the needs of agribusiness, no one else. We could import the ethanol from Brazil, where it is made much more cheaply (and with less use of natural resources) from sugar cane.

What we really need is a way of converting cellulose (not just starch) to usable fuel.

We certainly need to do something about global warming, or we will be in BIG trouble within your lifetime. But that is not a reason for doing things that make matters worse.