Gasoline octane quality and demand

Vehicle octane requirements have increased each year since 1975, and the automobile industry may further increase octane requirements to improve fuel economy. The technical (knock-related) need in 1979 for higher-octane unleaded gasoline is approximately 14Vertical Bar3<, and this is projected to grow to 19-23Vertical Bar3< of gasoline demand by 1985. If 1979 grade octane levels remain constant, the U.S. clear gasoline pool would have to increase 2.2 octane numbers (Research + Motor)/2 by 1980 to accommodate the original EPA lead phasedown to 0.5 g/gal. An arrest of the phasedown by continuation of current refining waivers and an elimination of the 0.5 g/gal limit on lead would virtually eliminate the increase needed in clear gasoline pool octane quality through 1981. The displacement of vehicles using leaded gasoline by vehicles using unleaded gasoline is producing a lead phasedown independent of the EPA requirement, but an arrest of the phasedown would increase gasoline availability and reduce crude oil requirements through 1981.