Identifying high power-Density stream reaches through refined geospatial resolution in hydropower resource assessment

Aided by the rapid development of multiple geospatial data sets for topography, hydrology, and existing energy-water infrastructures, reconnaissance-level hydropower resource assessment can now be conducted using geospatial models in all regions of the United States. The updated techniques can be used to estimate the total undeveloped hydropower potential across all regions, and they may eventually help to identify additional hydropower resources that were previously overlooked. To enhance the characterization of higher power-density stream reaches, this paper explored how the degree of geospatial resolution affects the identification of hydropower stream reaches, using the geospatial merit matrix-based hydropower resource assessment (GMM-HRA) model. GMM-HRA model simulation was conducted at eight different spatial resolutions on six USGS eight-digit hydrologic units with terrains classified as flat, mild, and steep. The results showed that more hydropower potential from higher power-density stream reaches can be identified with increasing spatial resolution. Both flat and mild terrains exhibited lower impacts from resolution differences than did the steep terrain. The findings indicate that greater care should be taken in selecting the discretization resolution for hydropower resource assessments in future studies.