When cellulosic ethanol will become commercially viable is a big question that has many answers.

There are those, for instance, who believe the challenges to making cellulosic commerically viable are too great to be overcome in less than a decade, maybe even two decades.

Agriculture Secretary Mike Johanns says, “You get some difference of opinion, but I really do think it’s fair to say that somewhere near the end of this decade, the first part of the next decade, you’ll see it as viable.” Johanns believes that is actually a conservative estimate – he is optimistic that commercial viability will happen sooner.

The question will be a topic at the National Ethanol Conference this week in Tucson, AZ. The answers will be explored during the final panel discussion of the conference on Wednesday by Nathanael Greene, Senior Policy Analyst with the Natural Resources Defense Council; Dr. Daniel De La Torre Ugarte, Associate Professor at the University of Tennessee; and Corey Radtke, Idaho National Laboratory scientist.

Follow the proceedings of the conference, which starts Monday, on the National Ethanol Conference blog.