Application of Biodiesel in Automotive Diesel Engines

Diesel engines due to the better fuel economy have been widely used in automotive area. However, the limited reserve of fossil fuel and deteriorating environment have made scien‐ tists seek to alternative fuels for diesel while keeping the high efficiency of diesel engine. Fuel consumption is expected to increase from 86 million barrels per day to 112 million bar‐ rels per day by 2035 according to the report published by US Energy Information Adminis‐ tration in 2011 [1]. The limited reserve cannot afford this usage. Another challenge is environmental deterioration and climate change. Excessive emissions of carbon dioxide (CO2) to the atmosphere are regarded as the leading cause of global warming. In addition, other emissions, such as NOx, SO2, also have a close relationship with other forms of climate change, such as photochemical smog and acid rain. Due to these, the regulations on fuel economy and emission limits are increasingly stringent. Table 1 shows the EU emissions regulations for passenger cars came into force since 1992.