A recent U.S. Supreme Court decision has limited the Environmental Protection Agency’s (EPA) powers. The decision in West Virginia v. Environmental Protection Agency curbs the EPA’s authority on power plant emissions, leaving the matter to the states. The case stems from the Obama-era Clean Power Plan regulations. The Clean Power Plan (CPP) set limits on power generation-borne carbon dioxide emissions across the country. As part of the plan, the states would be required to submit emissions reports to the EPA, which claimed the authority to intervene in non-compliant states via the Clean Air Act. The coal industry immediately challenged the plan, and several coal-producing states filed lawsuits against the EPA in federal court claiming that the EPA had overstepped its authority and that the plan would effectively end the U.S. coal industry. The CPP was put on hold while under litigation, and never took effect. At the same time, increased focus on carbon emissions put coal-fired plans under pressure to reduce their emissions, and the emergence of lower-cost and less-emissive natural gas as a fuel source led many plants to convert. The Trump Administration's Affordable Clean Energy Rule effectively nullified the Clean Power Plan, but was itself contested in the courts, eventually being vacated by the U.S. Court of Appeals for the D.C. Circuit. In response, the North American Coal Corp. appealed the decision to the Supreme Court, questioning the EPA’s legal authority to broadly regulate CO2 emissions through the Clean Air Act. In a 6-3 decision, the Supreme Court ruled in favor of West Virginia, citing that Congress did not give the EPA power to devise its own emissions-capping regulation. Chief Justice John Roberts, who wrote the majority opinion, argued that though the plan may be a “sensible solution” to the issue of climate change and greenhouse gas emissions, “it is not plausible that Congress gave the EPA the authority to adopt on its own such a regulatory scheme”. As such, the power is thus given back to the states, unless there is federal legislation passed to specifically give the EPA such powers. Though controversial, the ruling will likely have little effect in Pennsylvania, and other states with their own environmental protection agencies, laws, and regulations. In Pennsylvania, for example, the ruling does not affect the commonwealth’s decision to join the Regional Greenhouse Gas Initiative (RGGI). Pennsylvania officially implemented the rules associated with RGGI one day after the Supreme Court ruling. The authority of Pennsylvania to regulate carbon emissions comes from the Environmental Rights Amendment of the state constitution.
Carbon emissions will likely continue to be closely monitored even as states develop their own rules as the U.S. and other countries strive to meet climate goals set in the Paris Accord. As a result, the use of coal-fired plants is likely to decline as advances to make renewable energy more affordable and the use of cleaner-burning natural gas continues to increase.