Twenty years of trials, tribulations, and research progress in bioethanol technology - Selected key events along the way

The projected cost of ethanol production from cellulosic biomass has been r educed by almost a factor of four over the last 20 yr. Thus, it is now comp etitive for blending with gasoline, and several companies are working to bu ild the first plants. However, technology development faced challenges at a ll levels. Because the benefits of bioethanol were not well understood, it was imperative to clarify and differentiate its attributes. Process enginee ring was invaluable in focusing on promising opportunities for improvements , particularly in light of budget reductions, and in tracking progress towa rd a competitive goal. Now it is vital for one or more commercial projects to be successful, and improving our understanding of process fundamentals w ill reduce the time and costs for commercialization. Additionally, the cost of bioethanol must be cut further to be competitive as a pure fuel in the open market, and aggressive technology advances are required to meet this t arget.