Friday, the U.S. District Court for Colorado cleared the path for appellate review by the U.S. Court of Appeals for the 10th Circuit of the question as to whether Colorado can force renewable energy producers in other states to meet Colorado regulations. A three-judge panel in Colorado ruled they could, while the U.S. Court of Appeals in Minnesota ruled it was over reaching. That sets up a showdown in the U.S. Supreme Court. The Colorado renewable energy mandate establishes renewable quotas that can only be met through generation that meets Colorado’s renewable energy definitions. That means some of the renewable energy credits must come from other states, but they must meet Colorado regulatory definitions. The Colorado court held this was not “extraterritorial” regulation. The Minnesota Court held that it was. Because the law on these questions is unsettled, all 30 states with similar regulatory quotas will watch with great attention what next happens in the appellate court. As an environmental matter, the Colorado renewable energy mandate has had no meaningful impact on air quality within the State. Colorado met all National Ambient Air Quality Standards related to electricity production many years ago and the air has been safe to breathe ever since. The effect of the Colorado renewables quotas has no measureable effect on global warming or local weather or climate. At most, the Colorado energy quotas would prevent 0.00001 degree of warming.