美国能源情报署(EIA)的统计数据表明,2011年美国已首次成为62年来的净石油产品出口国。这个历史性转变的一个促因是乙醇和生物柴油快速进入运输燃料体系。生物燃料现在已成为全球运输燃料供应的贡献者。长期 Statistics from the U.S. Energy Information Administration (EIA) show that for the first time in 2011, the United States has become a net oil exporter for 62 years. A contributing factor to this historic shift is the rapid introduction of ethanol and biodiesel into the transportation fuel system. Biofuels have now become contributors to the global transportation fuel supply. long