Resource Accreditation in U.S. Resource Adequacy Mechanisms: Emerging Challenges and Solutions

Resource adequacy (RA) mechanisms in the U.S. are currently undergoing significant changes, to address several emerging challenges: an increase in extreme weather events, higher reliance on intermittent and energy-limited resources, retirement of older generation, and data center load growth. A key part of these changes is in how resources are credited toward RA needs (“resource accreditation”). 

This paper provides an overview of resource accreditation in U.S. RA mechanisms, the drivers behind recent changes in accreditation methods, and recent and forthcoming changes in resource accreditation in two regions: California and the Midcontinent Independent System Operator (MISO) region (see map, below). Other regions, including the PJM and ISO-NE regions, are also implementing major changes to their RA mechanisms, but California and MISO are most advanced in implementing changes to resource accreditation. The paper also discusses PJM’s current approach to resource accreditation, as an illustration of a region that is currently considering changes in its RA mechanism.