emissions would become highly negative. Because geologic storage of CO2 from biochemical conversion of biomass to fuels could be important in reducing greenhouse gas emissions in the transportation sector, it could be evaluated and demonstrated in parallel with a program of geologic storage of CO2 from coal-based fuels.
Future improvements in cellulosic technology that entail invention of biocatalysts and related biological processes could produce fuels that supplement ethanol production in the next 15 years. In addition to ethanol, advanced biofuels (such as lipids, higher alcohols, hydrocarbons, and other products that are easier to separate than ethanol) should be investigated because they could have higher energy content and would be less hygroscopic than ethanol and therefore could fit more compatibly into the current petroleum infrastructure than ethanol can. Large-scale commercial application of advances in biosciences (genomics, molecular biology, and genetics) and in biotechnologies to convert biomass directly to produce lipids, higher alcohols, and hydrocarbons fuels (that can be directly integrated into the existing transportation infrastructure) poses many challenges. These challenges will need to be resolved by R&D and demonstration if major advances in the production of alternative liquid fuels from renewable resources are to be realized. Research support from the federal government could help focus advances in bioengineering and the expanding biotechnologies on the development of advanced biofuels.
The need to expand the delivery infrastructure to meet a high volume of ethanol deployment could delay and limit the penetration of ethanol into the U.S. transportation-fuels market. Replacing a substantial proportion of transportation gasoline with ethanol will require a new infrastructure for ethanol’s transport and distribution. Although the cost of delivery is a small fraction of the overall ethanol fuel cost, the logistics and capital requirements for widespread expansion could present many hurdles if they are not well planned.
A comprehensive study could be conducted jointly by the DOE and the biofuels industry to identify the infrastructure system requirements of, the research and development needs in, and the challenges facing the expanding biofuels industry. Such a study would consider the long-term potential of truck or barge delivery versus the potential of pipeline delivery that is needed to accommodate increasing volumes of ethanol, in addition to the timing and role of advanced biofuels that are compatible with the existing gasoline infrastructure.