The Geospatial Raster Input Data for Capacity Expansion Regional Feasibility (GRIDCERF) data package has been developed to evaluate siting suitability for renewable and non-renewable power plants in the United States. It offers 264 suitability layers for use with 56 power plant technologies in a harmonized format that can be easily ingested by geospatially-enabled modeling software. The data package includes information on factors such as water stress, technology change, climate change, and socioeconomic change that affect power plant siting choices. The GRIDCERF data package provides suitability data for most of the electricity generating technologies represented in the 50-state U.S. version of the Global Change Analysis Model (GCAM-USA). The data has been validated against operational power plants and wind farms, and the results support the use of GRIDCERF for understanding potential regional-scale wind expansion. The data package is designed to be used with the Capacity Expansion Regional Feasibility (CERF) software, which simulates power plant siting for regional capacity expansion planning. GRIDCERF is the only open-source data package providing centralized data to evaluate power plant siting suitability in a harmonized, rasterized format for use with energy system expansion planning models. [f5bf8375]