Since the completion of the Pacific Intertie, the US’s first large-scale high-voltage direct-current (HVDC) transmission line built in 1970, HVDC technology has evolved dramatically. Today, HVDC transmission plays a critical role in grid modernization efforts around the world. However, deployment of HVDC lines lags behind in the US despite the need to dramatically expand the nation’s grid to efficiently move low-cost power long distances to meet increased demand and ensure reliable power supply.

In a new multi-client report, electricity experts from Brattle and DNV explain and summarize the capabilities of HVDC transmission technologies, review the operational experience that has already been gained with modern HVDC technologies, and summarize the planning, operational, and market benefits that these technologies now offer to regional power system operators. To address the challenges to the deployment of HVDC solutions, the authors recommend that grid planning authorities collaborate with transmission owners, HVDC equipment manufacturers, the North American Electric Reliability Corporation (NERC), industry groups, regulators, states, and the US Department of Energy (DOE) and its National Labs to:

  1. Develop and implement “grid codes” for interconnecting and embedding HVDC transmission that can allow grid operators to take full advantage of modern HVDC capabilities;
  2. Adapt grid planning tools and multi-value transmission planning frameworks to take full account of modern HVDC capabilities;
  3. Provide training for planning, engineering, and grid operations staff so they are able to take advantage of modern HVDC capabilities;
  4. Address current supply chain challenges by building manufacturing capability through clear long-term commitments;
  5. Develop standardized HVDC functional and interface requirements and vendor compatibility standards, taking advantage of experience gained in similar European efforts;
  6. Develop new regulatory and cost-recovery paradigms that can take advantage of the controllable nature of HVDC technology (both regionally and interregionally), including merchant transmissions to permit greater competition and allow for more financial risk sharing with transmission owners;
  7. Update grid operations to be able to take advantage of HVDC capability;
  8. Update market designs so system operators can co-optimize controllable embedded transmission with generation; and
  9. Implement optimization of interregional transmission capabilities that can accommodate merchant HVDC transmission.

The report, The Operational and Market Benefits of HVDC to System Operators, was coauthored by Brattle Principal Johannes Pfeifenberger; Associate Dr. Linquan Bai; Senior Consultant Andrew Levitt; and Cornelis Plet and Chandra Sonnathi of DNV. The report was prepared for GridLab, the American Council on Renewable Energy (ACORE), the Clean Grid Alliance (CGA), Grid United, Pattern Energy, and Allete.

The full report and a summary presentation of its findings – presented during an ACORE webinar and panel discussion – can be found below.

Report Summary

Full Report

Webinar Presentation

Webinar Recording

ACORE Press Release