Wide-Area Resource Adequacy Assessments: Probabilistic Planning for Interconnected Grids describes the need for, and key elements of, interconnection-wide or continental resource adequacy assessments. These wide-area resource adequacy assessments can provide a clearer understanding of how regions may be able to assist one another during system stress, while supporting and validating local and regional assessments.
Regions’ varied approaches to resource adequacy planning limit the ability to assess reliability risk across the broader electricity grid. While individual regions often plan conservatively to ensure local reliability, this approach overlooks the value of geographical diversity, the potential for external assistance, and the benefits of coordinated planning. Without a clear understanding of how regions may be able to assist one another during system stress, planners risk both overbuilding in some areas and underpreparing in others.
A wide-area resource adequacy assessment spans multiple regions and planning authorities, and can assess both near-term risks and long-term needs under shared assumptions about load, weather, outages, and transmission. The report discusses several ways that wide-area assessments can improve planning, including by supporting scenario consistency in local and regional assessments, increasing neighboring system visibility, evaluating the availability of external assistance, improving extreme weather event evaluation, and aligning methods and metrics.
A coordinated, probabilistic wide-area resource adequacy assessment is essential to ensure reliability, reduce unnecessary costs, help harmonize accreditation methods, and unlock the full value of coordinated reliability assistance and interregional transmission. By better aligning planning across regions, such an assessment provides a clearer picture of system-wide risks and supports smarter, more efficient investment and policy decisions.
