|Source:||National Renewable Energy Laboratory|
|Date:||1/1/95 Record No.: 10099|
|Contact:||Charles Wyman, 303-275-4453|
Alternate Fuels Division
Most current production of fuel ethanol is by fermentation of cane sugar or corn or other starch-rich grains (using enzymatic conversion of starches to sugar). However, the cellulose and hemicellulose in biomass materials such as agricultural and forestry residues, waste paper, municipal and industrial waste, and dedicated herbaceous and wood energy crops can also be converted into sugars for fermentation to ethanol
Significant refinements to these processes have made the concept financially and environmentally viable for direct blending of ethanol with gasoline. NREL has developed new procedures to improve fungi and bacteria that produce the enzymes ("cellulases") needed for hydrolysis. A major CRADA is underway with New Energy Company of Indiana to increase the ethanol yield from corn. Another CRADA with Amoco is directed at commercial production of ethanol from various cellulosic wastes that generally end up in land fills
NREL is also working to perfect a process called SSF (simultaneous saccharification and fermentation), which makes it possible to do both steps in one process. A new genetically engineered bacterial has just been developed that significantly reduces the costs for this process toward the goal of achieving costs competitive with gasoline as a pure fuel without subsidies.
Meanwhile, the market for ethanol is in a complex state of flux, as decisions are pending whether to choose ethanol, EBTE or other oxygenates as the additives for reformulated gasoline, for compliance with CAA requirements.
The Alternative Fuels Users Facility has a one-ton/day pilot plant that enables industry partners to test scale-up and integration of ethanol production methods. This is important for both the near term objectives in support of CRADAs and long-term technical improvements.
The Alternate Fuels Data Center provides a clearinghouse for information on performance, emissions, and operating and maintenance costs of using alternative transportation fuels .
Other programs are working on production of petrochemical feedstocks from biomass or waste materials; e.g., the recycling of plastics, all directed at reducing emissions (including CO2), reliance on petroleum, and landfill.