Yes indeed! Ethanol at >$3.00/gallon in a scalable production format would be a very significant development.  My calculations indicate that, at $100/B a  square mile of facility could generate >$6,000,000/year.  This would provide a strong incentive to build and a strong incentive to develop algae that could produce butanol, which would have the same energy density as gasoline. An awful lot of landowners within a mile or so of a coast would be interested in growing ethanol or butanol.  Competitive pressures would likely improve efficiency and drive the price down still further.

 

If sanity be culturally normative, then by the norms of this culture I claim insanity.