Hybrid Electric Vehicles, 2nd Edition

1Introduction

Modern society relies heavily on fossil fuel based transportation for economic and social development – freely moving goods and people. There are about 800 million cars in the world and about 260 million motor vehicles on the road in the United States in 2014 according to the US Department of Transportation’s estimate [1]. In 2009, China overtook the United States to become the world’s largest auto maker and auto market, with output and sales respectively hitting 13.79 and 13.64 million units in that year [2]. With further urbanization, industrialization, and globalization, the trend of rapid increase in the number of personal automobiles worldwide is inevitable. The issues related to this trend become evident because transportation relies heavily on oil. Not only are the oil resources on Earth limited, but also the emissions from burning oil products have led to climate change, poor urban air quality, and political conflict. Thus, global energy system and environmental problems have emerged, which can be attributed to a large extent to personal transportation.

Personal transportation offers people the freedom to go wherever and whenever they want. However, this freedom of choice creates a conflict, leading to growing concerns about the environment and concerns about the sustainability of human use of natural resources.

First, the world faces a serious challenge in energy demand and supply. The world consumes approximately 85 million barrels of oil every day but ...