Octane and the environment

One of the most important technical issues of the automotive fuel regulatory regime that has evolved in the United States since 1973 is the need to provide sufficient octane while at the same time meeting increasingly stringent fuel content requirements designed to reduce emissions and protect public health. There are several ways for refiners to provide octane and all of them have environmental consequences. This paper traces the technological and environmental trade-offs that have occurred from initial lead reduction rules in 1973 through the first phase of the reformulated gasoline program ending in 2000. Overall, increasingly stringent fuel regulations during this period have contributed to significant declines in pollutant emissions and concurrent reductions in risks to public health. Each improvement, however, was accompanied by a unique trade-off that sometimes led to unintended consequences. To address these trade-offs as they emerged, more regulation was required and additional trade-offs resulted. This analysis suggests that the complex process of gasoline regulation and the technological response to maintain octane quality is characterized by the continual emergence of new risks as the regulatory system evolves. This pattern demonstrates the omnipresence of risk trade-offs and potential for unintended consequences to occur as a result. Public perception, regulatory design, and technological choice influence the nature of these trade-offs and play an important role in addressing unintended consequences.