July 9, 2007
New U.S. coalition argues for caution in ethanol blends
Washington, D.C. – A new coalition, the Alliance of a Safe Alternative Fuels Environment (AllSAFE), has been formed with the mission to assure the “safe and successful introduction” of new bio-based and other alternative fuels, reports the Green Car Congress. The coalition wants to slow down increasing Congressional movement toward shifting to a higher, 20 per cent ethanol blend in the general national fuel supply, in addition to current E85 blends for flexible-fuel vehicles.
Thirteen member organizations make up AllSAFE, including the Alliance of Automobile Manufacturers, the Specialty Vehicle Institute of America, the Association of International Automobile Manufacturers, the Engine Manufacturers Association, and others representing motorcycles, marine industries, snowmobiles and power equipment.
The alliance notes that last month, the House Energy and Commerce Committee added an amendment to its energy bill, requiring an open, public process to review the impacts of renewable energy fuels on the environment, and on consumers and their products. However, a similar amendment was blocked during the Senate floor vote on its energy bill.
At its formation, AllSAFE released a report on the potential effects of mid-level ethanol blends – fuels with more than 10 per cent ethanol – on existing engines, vehicles, boats and equipment. “Important data gaps aside, with present knowledge, it is likely that there will be adverse, large-scale impacts if higher than E10 is required as motor gasoline for the existing fleet of on-road and off-road equipment, particularly the latter,” says Dr. Ranajit Sahu, author of the report. “Minimizing these likely adverse impacts on existing equipment and vehicles would require significant and expensive adaptation and mitigation measures.”
The report states that some of the changes in fuel properties due to the addition of ethanol include a change in octane number; changes in the energy density; water absorption; material compatibility; and the effect on emissions.
Sahu notes the number of changes that Brazilian automakers implemented in their vehicles to support the use of E20, but says that while there are international standards for E85, which cover formulations ranging from E70 to E85, there are no standards for mid-level blends between E10 and E70. He also notes that U.S. emission standards are more stringent than those in Brazil, and that U.S. vehicle manufacturers select oxygen sensors and onboard diagnostic systems (OBD) specifically to cover the expected range of oxygen in the exhaust gas. “If the fuel ethanol pushes the exhaust oxygen content outside the range of the oxygen sensor, the vehicle’s OBD system won’t work properly and may erroneously illuminate or fail to illuminate the dashboard warning light,” he says.