World Bank 2016a, Electric power transmission and distribution losses (% of output) Available at (http://data.worldbank.org/indicator/EG.ELC.LOSS.ZS). World Bank 2016b, Renewable electricity output (% of total electricity output). Available at (http://data.worldbank.org/indicator/EG.ELC.RNEW.ZS/countries). ZF 2013, ZF axle systems for city buses and coaches. Available at (http://www.zf.com/corporate/en_de/products/product_range/buses/buses_axles_ave130. shtml#tabs1-1) APPENDIX: Bus energy calculation Definitions A bus frontal area (m2) EFFC full fuel cycle energy (MJ/km) aa average acceleration (m/s2) engine and power train efficiency η Aa, Constants used in acceleration well to tank energy conversion efficiency ηwt Ba function acceleration multiplier- sets Ca N number of stops/km deceleration rate Cal accessory power load fraction Pmax max engine power (W) Cd drag coefficient R Regeneration factor Ci transmission mass multiplier ts time whilst stopped (sec) Cr rolling resistance ta time spent accelerating and decelerating (sec) distance travelled during da tc time spent on cruise (sec) acceleration (m) distance travelled during cruise dc td deceleration time (sec) (m) distance travelled during dd Vc maximum speed of cycle- cruise speed (m/s) deceleration (m) energy intensity of acceleration Ea Vave average cycle speed including stop time (km/h) (J/km) Eal Accessory load (J/km) ts time whilst stopped (sec) Ec energy intensity of cruise (J/km) ta time accelerating and decelerating (sec) EF fuel energy intensity (MJ/km) tc time spent on cruise (sec) Drive cycle As shown in Figure A, assume that the bus drive cycle is made up of a series of accelerations and decelerations followed by a stop, and a period of cruise. Figure A: Bus drive cycle with three acceleration and deceleration events with stops, and a period of cruise.
World Bank 2016a, Electric power transmission and distribution losses (% of output) Available at (http://data.worldbank.org/indicator/EG.ELC.LOSS.ZS). World Bank 2016b, Renewable electricity output (% of total electricity output). Available at (http://data.worldbank.org/indicator/EG.ELC.RNEW.ZS/countries). ZF 2013, ZF axle systems for city buses and coaches. Available at (http://www.zf.com/corporate/en_de/products/product_range/buses/buses_axles_ave130. shtml#tabs1-1) APPENDIX: Bus energy calculation Definitions A bus frontal area (m2) EFFC full fuel cycle energy (MJ/km) aa average acceleration (m/s2) η engine and power train efficiency Aa, Ba Constants used in acceleration function ηwt well to tank energy conversion efficiency Ca acceleration multiplier- sets deceleration rate N number of stops/km Cal accessory power load fraction Pmax max engine power (W) Cd drag coefficient R Regeneration factor Ci transmission mass multiplier ts time whilst stopped (sec) Cr rolling resistance ta time spent accelerating and decelerating (sec) da distance travelled during acceleration (m) tc time spent on cruise (sec) dc distance travelled during cruise (m) td deceleration time (sec) dd distance travelled during deceleration (m) Vc maximum speed of cycle- cruise speed (m/s) Ea energy intensity of acceleration (J/km) Vave average cycle speed including stop time (km/h) Eal Accessory load (J/km) ts time whilst stopped (sec) Ec energy intensity of cruise (J/km) ta time accelerating and decelerating (sec) EF fuel energy intensity (MJ/km) tc time spent on cruise (sec) Drive cycle As shown in Figure A, assume that the bus drive cycle is made up of a series of accelerations and decelerations followed by a stop, and a period of cruise. Figure A: Bus drive cycle with three acceleration and deceleration events with stops, and a period of cruise.
ATRF2016_Full_papers_resubmission_25.docx