An Electrification Solution For Istanbul Metrobus Line

Abstract

In the present case, Istanbul Metrobus Line is operated by Metrobus vehicle with internal combustion engines. This situation is not suitable and sustainable in terms of operating cost and environment pollution. If this line was operated with electric vehicles, it would have lower operation costs and would reduce harmful effects to the environment. As an alternative solution, in this thesis, economically and technically the most suitable electric vehicle solution is determined according to the requirement obtained by driving cycle, environmental conditions, passenger occupancy rates and characteristic of the vehicle. In July 2018, in order to determine the characteristic of the vehicle, a coast down test was performed with an 18 meter articulated Metrobus. Additionally, to create the driving cycle; position, velocity, acceleration and time data were acquired from a Metrobus in service with IMU and GPS. Passenger flow data were generated from data that were obtained from the bus operator company. So as to find out HVAC system requirement of the Metrobus, weather data of Istanbul is obtained from Turkish State Meteorological Service and with the solar position data calculated heat loads of the vehicle were determined according to ASHRAE Standard. According these data, all system requirements are obtained. ii First of all, according to power requirements of the 18-m articulated bus, the traction system is selected and a suitable gearbox ratio for that traction system is determined to fulfill the system requirements. Secondly, the most important sub-system for passenger comfort, HVAC, is selected in compliance with the weather data. Thirdly, charger and batteries of different chemistry are selected for different lines. Finally, two types of fleets with different charging strategies are designed. At the end of the study, fleets that have different batteries and different charging strategies are compared with each other and with current diesel Metrobus fleet. For the comparison cost of all components are obtained and total cost of ownership of these three fleets are calculated. The most suitable electrification solution is obtained according to these calculations.