Climate Progress: The Regional Greenhouse Gas Initiative had its first auction this week since lowering its cap -- and the results suggest the system is once again effectively reducing carbon emissions.
Encompassing nine states in the northeast, RGGI is a cap-and-trade system that started operating in 2008. It sets an overall cap on the amount of carbon dioxide that can be emitted by the participating states. Then it breaks that amount into permits -- each allowing for one ton of emissions in a given year -- and...