Reliability benefits of wide-area renewable energy planning across the Western United States

In response to near- and long-term market and policy shifts, power systems are integrating increasingly-distant renewable energy resources. No analyses quantify the spatial heterogeneity of resource adequacy contributions of renewables at the interconnection-scale in the United States, which would indicate the value to resource adequacy of integrating increasingly-distant renewables. To fill this gap, we develop a Monte Carlo-based probabilistic reliability model to estimate the effective load carrying capability (ELCC) of wind or solar generators. We apply our model to estimate the ELCCs of new solar or wind generators at 1406 locations across the Western Interconnection when contributing to each of five power pools within the Interconnection. Across the five power pools, we find solar ELCCs range from 0% to 44% and wind ELCCs range from 0% to 55% across the Western Interconnection. Solar ELCCs increase from east to west for all but one power pool, incentivizing integration of western renewables into eastern power pools. Deploying storage with wind or solar generators increases their ELCCs, with larger increases occurring at locations with lower renewable-only ELCC values. Thus, resource adequacy gains from deploying storage with renewables can partly substitute for those from integrating increasingly-distant renewables.