A recent article in Scientific American makes a lot of good points about carbon markets and emission trading. Perhaps most important among them is the recognition that the simple existence of a market cannot ensure good environmental outcomes: there must be strong and appropriately designed institutions backing it up. Otherwise, well-connected firms will be able to wriggle through loopholes, fraud will occur at an unacceptable level, and cheating will be endemic.
The article points out some of the big failures in carbon markets so far. Within the European Union Emission Trading Scheme, far too many permits to emit were distributed for free. As a result, their price collapsed in April 2006. Even worse, coal companies in Germany and elsewhere were given free permits to pollute, able to sell some of those permits for cash, and willing to charge their customers for carbon costs that never existed. Also problematic has been the prominence of HFC-23 (trifluoromethane) projects within the Clean Development Mechanism of the Kyoto Protocol. Getting rid of HFC-23 entirely should have only cost about $136 million. It has an absurdly high global warming potential (12,000 times worse than CO2), and is easy to destroy and replace with less problematic chemicals. So far, firms have been able to earn $12.7 billion for partial elimination. The authors of the article suggest that simply paying for the $136 million worth of equipment would be far more sensible than allowing firms to exploit the price difference between the value of emission reduction credits and the cost of eliminating HFC-23.
Other problems with markets include the difficulty of working out what emissions would have been in the absence of some change (the approach used for many carbon offsetting systems) and the way markets can encourage incremental approaches to emission reduction rather than the fundamental overhaul of industrial sectors and energy infrastructures.
None of this is to say that markets are not important. Indeed, carbon pricing is an essential component in the fight against climate change. What it shows is that participants in markets cannot be implicitly trusted, and neither can the governments operating them. There must be mechanisms for oversight and enforcing compliance and a constant awareness about possibilities for cheating or gaming the system. Insofar as it has helped people to develop a better sense of these things, the Emission Trading System of the EU has been a valuable front-runner.