The Committee on Regional Electric Power Cooperation (CREPC) welcomed the opportunity to provide comments on the report prepared for California Assembly Concurrent Resolution 188 (ACR 188) titled Impacts of Expanded Regional Cooperation on California and the Western Grid. ACR 188 requested that the California Independent System Operator (California ISO) conduct an independent report summarizing regional studies and policies that focus on the impact of expanded regional cooperation on California. The California ISO hired the National Renewable Energy Laboratory (NREL) to co-author the study and perform an independent review. The following comments address this preliminary report published for stakeholder review on January 13, 2023.