Tham khảo tài liệu 'biofuels, solar and wind as renewable energy systems_benefits and risks episode 1 part 5', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 84 D. Koplow R. Steenblik ethanol industry but they were overturned in a court challenge a year later Johnson and Libecap 2001 . MTBE methyl tertiary butyl ether a petroleum-derived additive emerged as the oxygenate of choice primarily because the oil industry already had more than a decade of experience using it as an octane enhancer. Then in 2004 concerns over the carcinogenicity of MTBE and contamination of groundwater from leaky storage tanks led several key states starting with California New York and Connecticut to ban the additive Yacobucci 2006 . By early 2006 nineteen other states had banned or limited the use of MTBE. The demise of MTBE was then accelerated by the Energy Policy Act of 2005 EPACT05 . In addition to not granting MTBE producers liability protection Congress decided that the oxygenate mandates had yielded mediocre results and so ended them. Effective 6 May 2006 non-oxygenated reformulated gasoline could be sold in most parts of the country Yacobucci 2006 . With MTBE effectively no longer an option ethanol remains as the main surviving competing fuel additive for increasing octane a position that has helped further boost demand for the More significantly EPACT05 also included the first federal purchase mandates for liquid biofuels. Referred to as the Renewable Fuels Standard RFS it fixed minimum consumption levels of particular specified fuels for each year with the mandated level rising over time. Most of the mandated volumes under present law are expected to be fulfilled by ethanol from corn. Current Policies Supporting Ethanol Using a standard economic classification scheme for industry support we provide an overview of the many types of incentives now in place to support the ethanol industry. As we were able to identify more than 200 support measures benefitting ethanol nationwide in 2006 some of which also cover biodiesel which is not discussed here this section provides illustrations rather than a catalog. Volume-Linked
