Investigation of the Use of Methanol-Gasoline Blends

About the report:

An 18-month field test was conducted to determine if the Virginia Department of Highways & Transportation should give serious consideration to the use of methanol as a substitute for gasoline in the operation of its motor vehicles. Five of the eight 1973 and 1974 model vehicles involved in the test were operated for a total of 92,000 miles on a fuel blend containing an average of 10.7% methanol and 89.3% lead-free gasoline. The fuel was dispensed from a commercial type gasoline blending pump by blending at the nozzle and by pumping directly from a storage tank containing a specified blend of methanol and gasoline. The vehicles operating on the blend averaged 4.0% fewer miles per gallon but were 1.3% more efficient from a miles/Btu standpoint than the vehicles operating on lead-free gasoline. Exhaust emissions data suggested that emissions are more dependent on carburetor adjustments than on the percentage of methanol in the fuel. Drivability was impaired enough in two of the vehicles operating on the blend to warrant carburetor modifications before the vehicles could be operated safely and satisfactorily because the addition of methanol made the fuel air mixture too lean for good engine performance and because the methanol was incompatible with certain fuel system parts. Since methanol and gasoline are not completely miscible at all temperatures and moisture conditions, a major effort was required to properly store and dispense the desired blend. From a consideration of economic and supply factors, it was concluded that the use of methanol-gasoline blends in Department vehicles would not be justified at this time. Implementation would require that special attention be directed to vehicular adjustments and to the storage and handling of the blends.

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