Comparative Studies on Life Cycle Costs (LCC) Between Diesel Powered and Compressed Natural Gas (CNG) Powered Bus in Shanghai City

Compressed natural gas (CNG) is often regarded as a cleaner fuel than diesel used in vehicles, but its economical performance is not clear. This article reports on a study that investigated the economic differences between a diesel-powered and a CNG-powered bus in Shanghai, China. The authors utilized life cycle cost assessment methods, using 2003 prices. Their results show that the life cycle costs of the CNG powered bus were less than the diesel bus, if the discount rates are below 8% and environmental costs are not included. If the environmental costs of air pollution are included, the life cycle costs of the CNG-powered bus is still less than the diesel bus. The authors remind readers that the price of diesel and CNG, environmental life cycle costs, and the discount rate adopted are the main factors that affect a comparative conclusion. They call for additional study on quantifying the environment costs of unit mass pollutants in China.