Well-to-Wheel Analysis of Energy Efficiency & CO2 emissions for Hybrids & EVs in India: Current Trends & Forecasting for 2030

A comprehensive Well-to-Wheel (WTW) analysis was performed to evaluate WTW energy use, efficiency & CO2 emissions for 12 vehicle/fuel configurations for a passenger sedan in the Indian context. The WTW analysis covered gasoline, diesel, and compressed natural gas (CNG) powered conventional vehicles, series hybrids, and plug-in series hybrids. In addition, hydrogen fuel cell-powered series hybrid and its plug-in version, along with a battery-electric vehicle, were also studied. The WTW analysis was repeated for a couple of electricity generation scenarios for the year 2030 to forecast future trends and finally for a couple of hydrogen production scenarios, where hydrogen was produced via electrolysis of water in addition to being produced from natural gas. The electricity pathway showed minimum Well-to-Tank (WTT) efficiency and maximum WTT CO 2 emissions among the five fuels being considered for the study for all three electricity generation scenarios. The hybridization of vehicles showed improvement in the Tank-to-Wheel (TTW) efficiency and reduction in TTW CO 2 emissions. Plug-in hybrid configuration of gasoline, diesel, CNG, and hydrogen showed higher TTW efficiency and lower TTW CO 2 emissions than the conventional and series hybrid configurations. Battery electric configuration showed the maximum TTW efficiency of 68.2% and was associated with zero TTW CO 2 emissions. For the current electricity generation scenario, diesel hybrid showed maximum WTW efficiency, and CNG series hybrid showed lowest WTW CO 2 emissions. With the decrease in % share of coal, increased % share of renewables and reduction in transmission and distribution losses, it is expected that there would be an increase in the WTW efficiency and decrease in WTW CO 2 emissions for plug-in hybrids and battery-electric vehicles. For the year 2030, assuming that 44% of electricity is generated from renewable sources, plug-in hybrids and battery electric vehicles showed substantial improvement in WTW efficiency, with diesel plug-in hybrid still showing maximum WTW efficiency, and CO 2 emissions being the lowest for the CNG plug-in hybrid. For the hydrogen generation scenarios, WTW efficiency was the lowest, and WTW CO 2 emissions were the highest for the fuel cell series hybrid electric vehicle when hydrogen was produced via electrolysis using electricity from the current grid mix. Hydrogen plug-in hybrid showed the highest WTW efficiency and zero WTW CO 2 emissions when hydrogen was produced via electrolysis of water using electricity generated from 100% renewable sources.