Quantifying land-use metrics for solar photovoltaic projects in the western United States
摘要
Growth in solar photovoltaic capacity supports grid decarbonization but can result in land transformation. Quantifying land–solar interactions is hampered by inconsistent methods and data. We develop a consistent, replicable framework to quantify land-solar interactions and apply it to annotated aerial imagery covering 719 solar photovoltaic projects (13,272 megawatts of installed capacity) connected to the Western Interconnection in the United States. We train a deep-learning convolutional neural network to characterize solar photovoltaic land footprints, post-process outputs with geospatial land-cover overlays, and compute land-use efficiency and energy-normalized land transformation per project. Across the sample, mean capacity-based land-use efficiency is 24.7 ± 15.2 watts per square meter and mean lifetime land transformation is 0.846 ± 0.722 square meters per megawatt-hour; regional differences and engineering choices explain project-level variability. Our open-source inventory and method enable more consistent large-scale assessments of planning, life cycle impacts, and ecological trade-offs of solar expansion.