Simulation model performance analysis of a multiple station shared vehiclesystem

As an alternative transportation paradigm, shared vehicle systems have beco me increasingly popular in recent years. Shared vehicle systems typically c onsist of a fleet of vehicles that are used several times each day by diffe rent users. One of the main advantages of shared vehicle systems is that th ey reduce the number of vehicles required to meet total travel demand. An a dded energy/emissions benefit comes when low-polluting (e.g., electric) veh icles are used in the system. In order to evaluate operational issues such as vehicle availability, vehicle distribution, and energy management, a uni que shared vehicle system computer simulation model has been developed. As an initial case study, the model was applied to a resort community in South ern California. The simulation model has a number of input parameters that allow for the evaluation of numerous scenarios. Several measures of effecti veness have been determined and are calculated to characterize the overall system performance. For the case study, it was found that the most effectiv e number of vehicles tin terms of satisfying customer wait time) is in the range of 3-6 vehicles per 100 trips in a 24 h day. On the other hand, if th e number of relocations also is to be minimized, there should be approximat ely 18-24 vehicles per 100 trips. Various inputs to the model were varied t o see the overall system response. The model shows that the shared vehicle system is most sensitive to the vehicle-to-trip ratio, the relocation algor ithm used, and the charging scheme employed when electric vehicles are used . A preliminary cost analysis was also performed, showing that such a syste m can be very competitive with present transportation systems (e.g., rental cars, taxies, etc.). (C) 1999 Elsevier Science Ltd. All rights reserved.