In 2009, the U.S. Congress considered but ultimately failed to enact legislation aimed at limiting U.S. greenhouse-gas (GHG) emissions. The bill under consideration at that time, the American Clean Energy and Security Act of 2009, was the last in a series considered over several years. Sponsored by Representatives Henry Waxman (D-California) and Edward Markey (D-Massachusetts), the bill passed the U.S. House of Representatives but failed to win sufficient support in the Senate. No legislation was enacted, and by 2010, both Congress and the White House had abandoned efforts to pass federal climate legislation.
Over months of contentious debate, while the Waxman-Markey bill and subsequent Senate action were being considered, millions of Americans were introduced for the first time to the phrase "cap and trade," a regulatory approach that first came to prominence in the 1990s as the centerpiece of a national program to address the threat of acid rain by limiting emissions of sulfur dioxide (SO2), primarily from electric power plants.
The 1990 SO2 cap-and-trade program was conceived by the administration of President George H. W. Bush and was widely viewed as a success. Yet cap and trade became a lightning rod for congressional opposition to climate legislation from 2009 through 2010.
Some of that hostility reflected skepticism about whether climate change was real and, if it was, whether humans played a key role in causing it. A larger group of opponents in Congress worried about the proper role of government and the costs of combating climate change, particularly given the lack of commitments for action by the large emerging economies of China, India, Brazil, Korea, South Africa, and Mexico. The congressional debate touched only lightly on the relative merits of various policy options to reduce greenhouse-gas emissions. Thus, cap and trade may not have been defeated on its merits (or demerits), but rather as collateral damage in the larger climate policy wars.
Congress (to the extent it did assess policy alternatives to cap and trade), as well as the broader community of analysts and observers in the late 2000s, raised a number of substantive questions about the merits of this policy instrument as a means for responding to a major environmental policy challenge of the sort posed by climate change:
- How do the costs of a market-based approach, such as cap-and-trade, compare with traditional regulatory policies to reduce pollution?
- Can market-based policies—and the markets they create—be trusted to reduce emissions? That is, are they environmentally effective?
- What are the distributional impacts of market-based environmental policies; who are the winners and losers?
- How well does a cap-and-trade system stimulate technological innovation, as compared with an environmental policy that sets performance standards, specifies technologies for reducing pollution, or both?
In May 2011, the Harvard Environmental Economics Program hosted a two-day research workshop and policy roundtable in Cambridge, Massachusetts, to reflect on these and other questions in light of twenty years of experience implementing the SO2 cap-and-trade program, established under Title IV of the Clean Air Act Amendments (CAAA) of 1990. Also known as the Acid Rain Program and the SO2 allowance-trading system, Title IV represented the first large-scale application of cap and trade to control pollution—in the United States or any other country. (Of course, the largest emissions trading program in the world is now the European Union Emissions Trading System (EU ETS), a greenhouse-gas, cap-and-trade system that was implemented in 2005 and whose design was influenced by the U.S. SO2 program.)
A "policy brief" synthesizing the main conclusions and insights that emerged from the May 2011 Harvard workshop and roundtable has just been released, The SO2 Allowance Trading System and the Clean Air Act Amendments of 1990: Reflections on Twenty Years of Policy Innovation. The workshop and roundtable—sponsored by the Alfred P. Sloan Foundation—featured a dream team of economists and legal experts who had conducted extensive research on the SO2 allowance-trading system, as well as leaders of non-governmental organizations and former government officials who had guided the formulation and passage of the CAAA.
The new policy brief examines the design, enactment, implementation, and performance of the SO2 allowance trading system, with an eye toward identifying lessons learned for future efforts to apply cap and trade to other environmental challenges, including global climate change. The first section provides background on the acid rain program and summarizes data and analysis on its benefits. Subsequent sections examine key questions regarding cost, environmental effectiveness, market performance, distributional implications, and effects on technology innovation. The report also examines the political context of the formulation, enactment, and implementation of the SO2 allowance-trading system. Finally, the conclusions feature some reflection on implications for climate change policy.
The participants in the research workshop were: Joseph Aldy, Assistant Professor of Public Policy, Harvard Kennedy School; Dallas Burtraw, Darius Gaskins Senior Fellow, Resources for the Future; Denny Ellerman, Part-time Professor, European University Institute, Robert Schuman Centre for Advanced Studies; Michael Greenstone, 3M Professor of Environmental Economics, Massachusetts Institute of Technology; Lawrence H. Goulder, Shuzo Nishihara Professor of Environmental and Resource Economics, Stanford University; Robert Hahn, Director of Economics, Smith School, University of Oxford; Paul L. Joskow, President, Alfred P. Sloan Foundation; Erin T. Mansur, Associate Professor of Economics, Dartmouth College; Albert McGartland, Director, National Center for Environmental Economics, U.S. Environmental Protection Agency; Brian J. McLean, Former Director, Office of Atmospheric Programs, U.S. Environmental Protection Agency; W. David Montgomery, Senior Vice President, NERA Economic Consulting; Erich J. Muehlegger, Associate Professor of Public Policy, Harvard Kennedy School; Karen L. Palmer, Senior Fellow, Resources for the Future; John Parsons, Executive Director, Center for Energy and Environmental Policy Research, MIT Sloan School of Management; Forest L. Reinhardt, John D. Black Professor of Business Administration, Harvard Business School; Richard L. Schmalensee, Howard W. Johnson Professor of Economics and Management, MIT Sloan School of Management; Daniel Schrag, Sturgis Hooper Professor of Geology, Harvard University; Robert N. Stavins, Albert Pratt Professor of Business and Government, Harvard Kennedy School; Thomas Tietenberg, Mitchell Family Professor of Economics, Emeritus, Colby College; and Jonathan B. Wiener, William R. and Thomas L. Perkins Professor of Law, Duke University Law School.
The participants in the policy and politics roundtable were: Robert Grady, General Partner, Cheyenne Capital Fund (1989–1991: Associate Director, Office of Management and Budget for Natural Resources, Energy & Science; 1991–1993 Executive Associate Director, OMB, and Deputy Assistant to the President); C. Boyden Gray, Principal, Boyden Gray & Associates (1989–1993: White House Counsel); Fred Krupp, President (1984–present), Environmental Defense Fund; Mary D. Nichols, Chairman, California Air Resources Board (1993–1997: Assistant Administrator for Air and Radiation, U.S. Environmental Protection Agency); Roger Porter, IBM Professor of Business and Government, Harvard Kennedy School (1989–1993: Assistant to the President for Economic and Domestic Policy); Richard L. Schmalensee, Howard W. Johnson Professor of Economics and Management, MIT Sloan School of Management (1989–1991: Member, President's Council of Economic Advisers); and Philip Sharp, President, Resources for the Future (1975–1995: Member, U.S. House of Representatives, Indiana, and Chairman, Energy and Power Subcommittee, House Committee on Natural Resources).
I want to acknowledge the contributions of all of these participants in the research workshop and policy roundtable, as well as the comments and edits some provided on earlier drafts of the policy brief. Their expertise and experience made this project possible. And, of course, I'm very grateful to the Alfred P. Sloan Foundation for having provided generous support for the workshop and for the preparation of the study. I hope you find it of interest and value.