URBAN MASS TRANSIT ENERGY USE AND CONSERVATION POTENTIAL

Presently bus and rail systems carry only 2.5% of the urban passenger traffic. Although mass transit carries only a tiny fraction of urban traffic, existing bus and rail systems are two to three times as energy efficient as automobiles. Transit efficiencies vary widely depending on city size, time of day, and type of route. Based on the limited data presented here, it appears that transit efficiency improves with increasing metropolitan area population. Bus system efficiency also depends strongly on both time of day and direction of flow. The energy implications of a number of recent transit improvements are discussed. Unfortunately, the energy impacts are slight-in part because transit now carries so few people relative to the total and in part because the increased ridership only slightly reduces automobile traffic. Thus the short-term energy-saving potential of improved and expanded transit service is small relative to the savings possible through measures that directly affect the automobile and its use.