Electric Vehicles in China: Emissions, Health Impacts, and Equity

E-bikes in China are the single largest adoption of alternative fuel vehicles in history, with more than 100 million e-bikes purchased in the past decade and vehicle ownership about 2× [time] larger for e-bikes as for conventional cars; e-cars sales, too, are rapidly growing. Electric vehicles (EVs) in China are being considered as a strategy to improve air quality, energy efficiency, and reduce health impacts due to transport emissions. Because EVs have different pollution sources, namely electric generating units (EGUs), quantitative analysis for health impacts requires understanding the exposure efficiency of related pollution sources. In this dissertation, EVs will be analyzed in the context of the impacts on the environment, the differences in exposure efficiency of pollutants, the impacts on health, and the distribution of those impacts among different sectors of the population. This study compares emissions (CO₂ [Carbon Dioxide], PM_2.5 [Particulate Matter], NO_X [Nitrogen Oxide], HC [Hydrocarbon]) and environmental health impacts (primary PM_2.5) from the use of conventional vehicles (CVs) and EVs in 34 major cities in China. CO₂ emissions (g km^-1) vary and are an order of magnitude greater for e-cars (135–274) and CVs (150-180) than for e-bikes (14–27). PM_2.5 emission factors generally are lower for CVs (gasoline or diesel) than comparable EVs. However, intake fraction is often greater for CVs than for EVs because combustion emissions are generally closer to population centers for CVs (tailpipe emissions) than for EVs (EGU emissions). For most cities, the net result is that primary PM_2.5 environmental health impacts per passenger-km are greater for e-cars than for gasoline cars (3.6× on average), lower for e-cars than for diesel cars (2.5× on average) and equal between e-cars and diesel buses. In contrast, e-bikes yield lower environmental health impacts per passenger-km than the three CVs investigated: gasoline cars (2×), diesel cars (10×), and diesel buses (5×). In addition, adoption of EVs could cause environmental equity problems in China at this time, since a vast majority (>83%) of pollutant emissions inhaled and subsequent health effects due to urban EV use could be distributed to communities whose incomes are lower than the cities where EVs are promoted. The findings highlight the importance of considering exposures, and especially the proximity of emissions to people, when evaluating environmental health impacts and equity concerns for EVs.