Outcomes and timelines for state-based energy facility permitting in the United States

Permitting is a critical process shaping the pace, scale, impacts, cost, and distribution of energy supply. This study documents recent timelines and outcomes of state-based permitting processes for wind and solar projects across 19 states in the U.S. Ninety percent of projects obtained permit approval and most within a year or so of entering the process. State-level policies for permitting vary considerably, and two states (KY, MS) have substantially shorter average timelines than other states in our sample. Additional research is needed to identify factors responsible for the outcomes and timelines and clarify how different permitting regimes influence important factors such as public participation in permitting or the environmental impact of projects.