For each of the past eight years, EPRI’s research program on Integrated Energy System Planning, Fuels, and Market Analysis (Project Set 178-B) in conjunction with member electric companies has developed different scenarios of potential future technology, regulatory, and market conditions that may exist in the United States in the coming decades, and then analyzed how the United States electric sector might evolve under these scenarios. This report, and the accompanying slide presentation and Excel spreadsheet dataset, highlights the analysis conducted and results from our 2020 REGEN Scenarios Analysis Project. In 2020, we analyzed how the U.S. electric power generation mix may evolve from 2020 to 2050 under a 2020 Reference scenario and twelve different scenarios. These scenarios explored low carbon dioxide (CO2) emissions targets, with a goal of achieving 0%, 5% or 10% CO2 emissions by 2050 compared to 2020. These scenarios also explored the potential impacts of key sensitivities including: (i) capital costs for new nuclear generation; (ii) capital costs for wind and solar photovoltaics (PV); and (iii) limitations on future construction of new inter-regional transmission infrastructure. The results focus on a deep dive into power system investment decisions in 2040.