Regulated firms in pollution permit markets with banking

This paper examines a competitive intertemporal market for bankable emission permits, such as sulfur dioxide allowances. Without profit regulation, firms are willing to bank permits if permit prices rise over time with the rate of interest, but will not bank if prices rise more slowly.The market achieves aggregate emission targets at least total cost if there is no profit regulation, but may not do so if firms are subject to profit regulation. Firms must arbitrage differences both in abatement cost and in the regulatory treatment of permits to achieve least total cost.The impetus for this work came from research we initiated during the Summer of 1990 for the Energy Information Agency. We would like to thank Chuck Howe for his detailed comments and enthusiasm, and Jim Alm, Dave Bjornstad, Charles deBartolome, Mike Greenwood, Robert Hahn, Douglas Hale, Carolyn Lang, Jim Markusen, Edward Morey, Till Requate, and Tom Tietenberg. We are grateful to the editor and two anonymous referees for stressing the importance of regulation in these markets and for their helpful and clarifying advice.