This report begins by looking at the current production capacity of the oil refineries operating in the United States, and the sources and changes in crude oil supply. It then examines the changing characteristics of petroleum and petroleum product markets and identifies the effects of these changes on the refining industry. The report concludes with discussion of the policy and regulatory factors that are likely to affect the structure and performance of the industry during the next decade.

" The U.S. petroleum refining industry-the largest refining industry in the world-experienced a period of high product prices and industry profits from the early 2000s through about 2007. Since the recession of 2007 to 2009, the industry has been in transition. Federal and state agencies regulate petroleum refining and the use of petroleum products to protect human health and the environment, as well as for other purposes. EPA, DOT, and California recently proposed or strengthened five key regulations, including EPA and DOT's coordinated fuel economy and GHG vehicle emission standards, and EPA's RFS, which has required that refiners and others ensure transportation fuels include increasing amounts of renewable fuels such as ethanol produced from corn. GAO was asked to provide information on the domestic petroleum refining industry. This report examines: (1) major changes that have recently affected the industry and (2) the future of the industry. GAO reviewed information including studies by agencies and consultants and company financial filings; interviewed stakeholders, including agency officials and representatives of refiners and environmental organizations; and reviewed forecasts by the Energy Information Administration and others. "