I. BACKGROUND
As China enjoys its booming economy, its environmental issues are gaining more and more attention from the government. According to CleanTech Group's report, China is expected to be the largest energy consumer after 2010. As China's economy and energy consumption grow rapidly, the greenhouse gases emissions from fossil fuels are soaring simultaneously. Car sales in China, which surpassed Japan in 2007, are expected to surpass the United States by 2015. Increasing car sales will lead to fostering demand for oil and severe toll on the environment. China also faces severe water shortage and water pollution, especially in Northern China.