Implications of alternative emission trading plans: Experimental evidence

Two approaches to emissions trading are cap-and-trade, with an aggregate cap on emissions distributed as emission allowances, and baseline-and-credit, with firms earning emission reduction credits for emissions below baselines. Theory suggests the long-run equilibria of the plans will differ with baselines proportional to output. To test this prediction we develop a computerized environment in which subjects representing firms can adjust their emission rates and capacity levels and trade emission rights in a sealed-bid auction. Demand for output is simulated. We report on six laboratory sessions with variable emissions rates, but fixed capacity: three each with the cap-and-trade and baseline-and-credit mechanisms.