As with other commodity markets, markets for trading pollution permits have not been immune to market power concerns. In this paper, I survey the existing literature on market power in permit trading but also contribute with some new results and ideas. I start the survey with Hahns (1984) dominant-firm (static) model that I then extend to the case in which there are two or more strategic firms that may also strategically interact in the output market, to the case in which current permits can be stored for future use (as in most existing and proposed market designs), to the possibility of collusive behavior, and to the case in which permits are auctioned off instead of allocated for free to firms. I finish the paper with a review of empirical evidence on market power, if any, with particular attention to the U.S. sulfur market and the Southern California NOx market.

Chile has pioneered the implementation of emission offseting programs pursuing simultaneously economic growth and environmental protection. In this paper, emission trading programs implemented in Santiago of Chile are analyzed and its relevance for developing countries is evaluated. It is argued that emission trading programs can be the best tool to deal with air pollution problems even in cases in which the institutional capacities are not well developed. Moreover, the inclusion of the transport system into the emission trading programs and the possibility of moving towards a system of interpollutant exchange are both nouvelle and relevant elements in the context of air pollution control policies. However, these innovations involve rather more complex elements in the design of emission trading programs.

This paper provides an empirical evaluation of the efficiency of allowance banking (i.e., abating more in early periods in order to abate less in later periods) in the nationwide market for sulfur dioxide (SO2) emission allowances that was created by the U.S. Acid Rain Program. We develop a model of efficient banking, select appropriate parameter values, and evaluate the efficiency of observed temporal pattern of abatement based on aggregate data from the first eight years of the Acid Rain Program. Contrary to the general opinion that banking in this program has been excessive, we find that it has been reasonably efficient. We also show that this optimal banking program is robust to the errors in expectation that characterized the early years of this program; however, this property is due to design features that are unique to the U.S. Acid Rain Program.

We consider an infinitely-repeated oligopoly in which at each period firms not only serve the spot market by either competing in prices or quantities but also have the opportunity to trade forward contracts. Contrary to the pro-competitive results of finite-horizon models, we find that the possibility of forward trading allows firms to sustain collusive profits that otherwise would not be possible. The result holds both for price and quantity competition and follows because (collusive) contracting of future sales is more effective in deterring deviations from the collusive plan than in inducing the previously identified pro-competitive effects.