Comparative analysis of automotive powertrain choices for the near to mid-term future

Abstract

This thesis attempts a technological assessment of automotive powertrain technologies for the near to mid term future. The powertrain types to be assessed include naturally aspirated gasoline engines, turbocharged gasoline engines, diesel engines, electric hybrids using gasoline engines and advanced transmissions. Advancements in aerodynamics, weight reduction and tire rolling friction are also taken into account. The basis for the comparison is the potential of these powertrain technologies for reduction of oil consumption and green house gas emissions at the same level of performance as current vehicles. The fuel consumption and performance of future vehicles was estimated using simple scaling laws and vehicle simulations. The results indicate that the potential for reduction of fuel consumption is significant for all the powertrains examined. More specifically, it seems that the current relative advantage of diesel over gasoline engines in terms of fuel consumption is reduced. Future turbocharged gasoline engines especially, seem to become almost equivalent with diesel engines.

(cont.) Hybrids electric vehicles do maintain a competitive advantage over other powertrains in terms of reduction of fuel consumption. This advantage is however much more pronounced for urban than for highway driving.