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Energy Transmission

Bulk Power System

The generating resources and high-voltage transmission equipment that make up the backbone of the U.S. electricity grid constitute the bulk power system. The bulk power system does not include local distribution systems, which generally operate at lower voltages. Obligated with ensuring safe, reliable, and affordable services for customers in their states, public utility commissions have an inherent interest and responsibility in understanding and supporting a robust bulk power system. As the electricity system is changing, new issues, challenges, and opportunities are arising at the bulk power system level and between the distribution system and bulk power system. These issues can include resource adequacy, system stability, system reliability, market design, electricity planning, impacts of distributed energy resources and storage on the bulk power system, and more.

In 2021, NARUC began offering training on bulk power system issues, which complements other NARUC initiatives, such as Distribution Systems and Planning trainingNARUC-NASEO Task Force on Comprehensive Electricity Planning, and National Council on Electricity Policy (NCEP) annual workshops.

  • Resource Adequacy Primer for State Regulators, July 2021

    This primer was developed by the National Association of Regulatory Utility Commissioners (NARUC) and is intended to be used as an aid to state commissioners, their staff, and the regulatory community to provide a basic explanation of resource adequacy practices throughout the United States.

  • NRRI Insights Report: The Intersection of Decarbonization Policy Goals and Resource Adequacy Needs: A California Case Study, March 2021

    This piece explains the changing role of resource adequacy in the context of pressing industry issues such as: the rapid retirement of baseload and dispatchable generation; the state regulator’s finding that future procurement decisions should balance RPS requirements with resource adequacy needs; the continued development of advanced reliability metrics, which can help bridge the gap between decarbonization policy goals and resource adequacy needs; and the state’s responses to the ongoing supply shortages.

  • Battery Energy Storage Technology Adoption & Electric Utility Structure, September 2020

    This research paper explores the extent to which the structure of investor-owned utilities in vertically integrated and restructured states may influence the commercialization of battery energy storage (BES) and enable storage to contribute to a low-carbon electricity transition. The report identifies barriers and drivers of adoption of BES, including cost, externalities, institutional design, market design, innovation treatments, regulatory support, and political feasibility. The report specifically categorizes, summarizes, and examines the correlation between policy and market support for BES and number and size of BES installations.

  • NARUC-NASEO Task Force on Comprehensive Electricity Planning Library

    Through the Task Force on Comprehensive Electricity Planning, Task Force members, NARUC and NASEO staff, technical and subject matter experts, and others have developed a robust set of resources to support state decision makers in advancing aligned electricity system planning processes, including distribution, resource, and transmission planning. The Comprehensive Electricity Planning Library enables further learning about important issues related to comprehensive electricity planning by linking to existing publications and webinars. The library is organized across 15 key topical areas.

  • National Council on Electricity Policy Transmission & Distribution Coordination Resource Catalog

    The National Council on Electricity Policy (NCEP) T&D Resource Catalog documents an ongoing conversation about the intersection and coordination of the transmission and distribution systems. The documents contained in the resource catalog provide state electricity system decision-makers with examples and resources to support their decision making. Resources are organized into categories of: Planning, Operations, and Markets.

  • Innovations in Electricity Modeling Training Series, October-November 2021
    The National Council on Electricity Policy (NCEP) and Lawrence Berkeley National Laboratory will offer training on innovations in electricity system modeling, in partnership with Pacific Northwest National Laboratory and National Renewable Energy Laboratory, on October 1, October 12, October 20, and November 1, 2021. Participants will learn:

    • What modeling tools and methods are available to plan distribution and bulk power systems with distributed energy resources (DERs), including comprehensive planning approaches.
    • How utilities analyze utility-scale and distributed storage in integrated resource planning, ways state officials can review the analysis, and how to improve evaluation of storage in planning.
    • How to assess technical and economic impacts of DERs for distribution and bulk power systems, and what changes are needed in load forecasting, potential assessments, and modeling to treat energy efficiency and demand response on a comparable basis to other resources during planning.
    • Ways to improve planning throughout the electricity system in the face of climate change.

    Learn more

  • Bulk Power System Issues Training Series, May-June 2021
    NARUC, NASEO, and NASUCA partnered with Energy Systems Integration Group (ESIG) to offer a series of four training sessions on the reliability of the bulk power system. Sessions introduced non-technical attendees to key technical concepts and their practical applications in an evolving electricity system. The four-part course included discussions of: resource adequacy, balancing of the system in daily operations, system stability, and impacts of DERs on the bulk power system. Recording and presentations are available. Learn more

  • NARUC Electricity Committee Session: A Primer on Transmission: Basics and More, May 21, 2021


    • Daniel Hall, American Clean Power
    • Jay Caspary, Grid Strategies
    • Steve Gaw, Advanced Power Alliance

    View recording

    View presentation

  • NARUC-NASEO Task Force: Transmission Planning Coordination in Comprehensive Electricity Planning, July 7, 2020
    This webinar focused on key issues related to coordination between distribution planning, resource planning, and utility and RTO transmission planning processes. Speakers shared experiences and real-world examples of how DER growth affects transmission planning; how DERs are used to meet or offset transmission needs; and how states, utilities, and RTOs can coordinate planning to meet future goals for the electricity system.


    • Dan Robicheaux, Planner, Policy Regulatory Planning, Midcontinent Independent System Operator (MISO)
    • Neil Millar, Vice President of Transmission Planning & Infrastructure Development at the California ISO
    • Nick Chaset, Chief Executive Officer, East Bay Community Energy (EBCE)
    • Doug Scott, Vice President of Strategic Initiatives, Great Plains Institute

    View recording

    View presentation

NARUC thanks Energy Systems Integration Group (ESIG) for its partnership in providing training to NARUC, NASEO, and NASUCA members.

NARUC staff experts who support these activities include: