Yale Environment 360: A large majority of U.S. states 42 of 50 have already cut power plant carbon emissions ahead of the Environmental Protection Agency's Clean Power Plan, whose rules will be finalized next month, according to an analysis published this week. The plan requires each state to limit emissions from its power plants; to do this, many states have closed coal-fired plants and replaced them with natural gas power plants, which release less carbon dioxide. In fact, the report found, the 42 states that have...