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.