Executive Summary

America’s electricity grid is the foundation of a modern and growing economy, yet the existing transmission system is rapidly approaching its capacity limits. The rapid rise of domestic manufacturing, the electrification of transportation and industrial sectors and the emergence of Artificial Intelligence (AI) are driving unprecedented electricity demand. At the same time, much of the electricity transmission system is more than 25 years old, and must be upgraded or replaced. Expanding the grid is essential to meeting growing demand, keeping electricity affordable and ensuring America can outcompete China. Meeting future demand will require both new transmission infrastructure and innovative technologies that can expand the capacity of the existing grid.

Greenfield transmission projects expand the grid by creating new paths that move electricity from new and remote generation sources to load centers. They are critical for unlocking remote resources, such as geothermal, and for enabling new power plants, including advanced nuclear reactors, to deliver power to the grid. But historically, many of these projects have taken a decade or more to complete due to barriers related to permitting, siting, cost allocation and litigation.

As a result of these challenges, increasing attention is paid towards innovative grid technologies that can unlock more capacity on existing infrastructure faster and at a lower cost than greenfield development. This suite of technologies includes conductors with higher ampacity, or current-carrying capacity, that replace existing wires to increase power transfer over existing transmission paths. However, these technologies are underutilized due to their perceived risk, misaligned investment incentives and limitations in today’s transmission modeling tools.

Existing transmission software models can either plan for the long-term future of the grid or determine whether the system can operate reliably under worst-case conditions, but not both at the same time due to computational limitations. This means that existing models cannot optimize transmission expansion while also accounting for engineering and reliability constraints. As a result, long-term planning frameworks can’t evaluate the cost-optimal mix of transmission expansion options – like greenfield transmission, reconductoring with high-ampacity conductors, or deployment of other innovative grid technologies – to meet growth while maintaining reliability.

To address these analytical limitations, Evolved Energy Research (EER) developed a proof-of-concept integrated transmission model that bridges the gap between capacity expansion and power flow modeling. Using the Electric Reliability Council of Texas (ERCOT) system as a test-bed, this report finds that an integrated modeling approach is both a possible and powerful means to identify the opportunity and role for high-ampacity conductors and high-voltage transmission to meet surging demand reliably and affordably.

Key takeaways from this analysis include:

1. Cost-optimal grid expansion requires both reconductoring and new greenfield transmission. A reconductoring-only approach with commercially mature technologies could fail by 2030 without new greenfield transmission expansion. A greenfield-only approach is not fast enough to meet near-term demand growth and is more expensive and land-use-intensive.
2. Composite Core Conductors are the workhorse of near-term grid expansion. In the high data center demand case, nearly 75% of the capacity added to the grid by 2030 comes from reconductoring existing corridors. By 2040, reconductoring saves an estimated $20 billion in transmission investment and avoids 6,500 additional miles of greenfield transmission. Composite core conductors are the most cost-competitive technology deployed for reconductoring and for greenfield transmission, too.
3. Greenfield transmission is essential to creating a network capable of supporting demand growth. Greenfield transmission is vital for establishing new pathways, unlocking economic growth and energy resources across the state and maintaining reliability-based contingency standards.
4. Transmission expansion of all types is an affordable technology solution that complements generation. Transmission investment – for both reconductors and greenfield lines – is key to meeting demand growth and enabling energy addition affordably. Across all scenarios, expanding the bulk transmission system represents just 7-8% of total system investment by 2040.

Policy Recommendations

1. Regulatory Reform
   1. Establish Conductor Standards with Rebuttable Presumptions: Regulators could make high-ampacity composite conductors the default option in utility planning processes for lines facing thermal constraints while enabling utilities to make the case for alternative technologies.
2. Support the Next Generation of Transmission Planning Tools and Practitioners
   1. Fund Next-Generation Modeling Tools: The Department of Energy (DOE) could provide grants, technical assistance and national laboratory model development to help grid operators and utilities develop and implement transmission planning tools that more effectively assess deployment opportunities for advanced transmission technologies.
   2. Enhance Data Access and Transparency: Increasing access to information necessary to identify cost-effective deployment opportunities or barriers to advanced transmission technologies can facilitate cost-effective deployment.
   3. Expand Advanced Technology Evaluation to More Transmission Planning Processes: State and Federal entities could provide additional direction for utilities and other transmission planning entities to evaluate advanced transmission technologies during all planning, generation interconnection and large-load interconnection processes.
   4. Integrate Interconnection Needs in Transmission Planning: Improve coordination among transmission planning, load interconnection and generation interconnection to build more efficient transmission infrastructure.
   5. Leverage DOE Funding to Support Research, Development, Demonstration and Deployment: Bipartisan federal initiatives, including the Transmission Facilitation Program (TFP), Energy Dominance Financing (EDF) and Speed to Power through Accelerated Reconductoring and other Key Advanced Transmission Technology Upgrades (SPARK), provide crucial funding to de-risk and commercialize advanced grid technologies.
3. Siting and Permitting Modernization
   1. Effective Implementation of CITAP: Ensure robust staffing and support for the Department of Energy’s Coordinated Interagency Transmission Authorizations and Permits (CITAP) program to successfully reduce federal transmission permitting timelines.
   2. Enact Federal Permitting Reforms: Streamline environmental reviews under the National Environmental Policy Act (NEPA) and reform judicial review timelines to decrease litigation risks and delays for vital transmission projects.
   3. Improve Sub-National Coordination: Encourage states, localities and Tribes to form multi-jurisdictional task forces to harmonize and streamline transmission approvals.