Credible projections of future changes in climate, energy, and related human and natural systems are dependent on realistic scenarios of future electricity system growth. However, electricity capacity expansion models typically do not account for water availability, interconnection costs, regulatory constraints, or other factors that may restrict power plant construction. A team from the U.S. Department of Energy’s Pacific Northwest National Laboratory used the Capacity Expansion Regional Feasibility (CERF) model to evaluate the potential for siting different energy production technologies over the contiguous United States at a resolution of 1 km2.
By accounting for economic, environmental, and practical constraints that influence power plant siting, CERF will improve projections of future energy system growth and, ultimately, attendant changes in the integrated human-Earth system. Improved understanding of electricity capacity expansion constraints can also provide insight into factors that may influence long-term energy system resilience.
The open-source CERF model evaluates the feasibility of electricity capacity expansion plans by considering a wide range of factors that restrict power plant siting, including land use, environmental regulations, water availability, infrastructure access, and net operational costs. By combining this high-spatial-resolution information with larger-scale information about energy supply and demand from an integrated human-Earth system model such as GCAM, CERF can provide a comprehensive assessment of how many power plants of each type can be accommodated across a given region under a given scenario. Power plant siting is first evaluated based on geospatial suitability, which includes 32 base constraint layers and an additional seven layers of technology-specific constraints for 17 different power production technologies. The feasibility of the expansion plan is then further evaluated by considering economic factors such as the distance to existing transmission infrastructure, technology-specific marginal operating costs, and technology- and location-specific marginal energy values. Finally, an economic optimization algorithm is used to assign power plants to each 1 km2 grid cell. CERF thus provides a holistic, multi-sector, multi-scale assessment of the on-the-ground feasibility of a given electricity capacity expansion scenario. This information can be used to evaluate and refine projections of future energy system growth, which is a key factor driving future Earth system changes.