New modeling from ClearPath and Evolved Energy Research offers an important perspective on how advanced conductors, reconductoring and strategic greenfield development can work together to meet unprecedented electricity demand
America's transmission challenge is increasingly being described in terms of scale: how many miles of transmission must be built, how many gigawatts of new generation must be interconnected, and how quickly the grid can accommodate rapidly growing demand from data centers, artificial intelligence, manufacturing, electrification and other sources. Those are important questions. But an equally important question is beginning to receive greater attention: How much useful capacity and long-term value can we obtain from every transmission corridor and every dollar we invest?
A new report from ClearPath, Amping Up the Grid: The Role of High Ampacity Conductors in Transmission Expansion, offers an important contribution to that discussion. Authored by Casey Kelly and Will Bryant, with technical modeling and analysis performed by Evolved Energy Research (EER), the study uses ERCOT as a test bed for an integrated transmission modeling approach that evaluates both capacity expansion and power-flow requirements. Rather than beginning with a predetermined preference for reconductoring or new transmission, the model attempts to identify the cost-optimal combination of technologies and expansion pathways while maintaining system reliability.
The resulting message is both straightforward and important: America needs to build new transmission, and it also needs to make substantially better use of the transmission infrastructure it already has. These strategies are not competing alternatives. Properly planned, they reinforce one another.
Moving Beyond the Reconductoring-versus-Greenfield Debate
One of the strongest aspects of the ClearPath analysis is its rejection of a false choice that has sometimes shaped the transmission discussion. Reconductoring cannot eliminate the need for new transmission corridors. Likewise, relying primarily on new greenfield construction overlooks enormous opportunities to increase capacity on existing infrastructure faster and often at substantially lower cost.
In the study's high-demand case, nearly 75 percent of the capacity added by 2030 comes from reconductoring existing corridors. By 2040, the analysis estimates that reconductoring can save approximately $20 billion in transmission investment while avoiding roughly 6,500 miles of additional greenfield transmission. At the same time, the model concludes that greenfield transmission remains essential for establishing new pathways, supporting network reliability, accessing new generation and load centers, and strengthening portions of the system where existing topology cannot accommodate the required growth.
That distinction matters. Transmission capacity is not simply a function of how much current an individual conductor can carry. The surrounding network must also be capable of accepting and redistributing that power under normal and contingency conditions. ClearPath's analysis finds that reconductoring is particularly attractive in meshed networks with redundant paths, while greenfield transmission becomes increasingly important where networks are sparse or radial.
This suggests a more useful planning philosophy: upgrade where the network can support substantially greater capacity, strengthen the network where it cannot, and build new corridors where new pathways are genuinely required.
Composite-Core Conductors Move Toward Center Stage
Perhaps the most noteworthy result of the study is the role played by composite-core conductors. ClearPath describes them as the “workhorse of near-term grid expansion.” Across its scenarios, composite-core conductors are deployed most frequently, reflecting their performance advantage relative to conventional conductor technologies and their cost advantage relative to emerging high-temperature superconductors. The analysis also reports that ACSS is not selected for reconductoring in any modeled scenario.
There is an important engineering reason behind that result. Composite-core conductors replace the traditional steel core with substantially lighter materials that exhibit much lower thermal expansion. That combination enables greater aluminum content within a comparable conductor envelope while reducing high-temperature sag. ClearPath notes that replacing a conventional conductor with a composite-core design can potentially double the amount of energy transferred over the same right-of-way.
But the larger significance of the study is not simply that composite-core conductors perform well. It is where the model chooses to use them.
The analysis finds composite-core technology attractive not only for reconductoring existing lines, but also for new greenfield transmission. In fact, the Executive Summary identifies composite-core conductors as the most cost-competitive technology deployed for both applications.
That finding deserves greater attention.
For much of the industry, advanced conductors have historically been associated with solving difficult reconductoring problems: doubling capacity within an existing right-of-way, avoiding tower replacement, maintaining ground clearances, or addressing a thermal bottleneck. Those applications remain extremely important. But if a higher-performing conductor can deliver greater capacity, lower sag and greater design flexibility on an existing structure, many of those same characteristics deserve consideration when engineers are designing an entirely new transmission line.
The question should increasingly become not simply “What conductor will satisfy today's rating requirement?” but “What conductor and line design will create the greatest useful infrastructure value over the next 40, 50 or 60 years?”
From Lowest Initial Cost to Lifetime Infrastructure Value
That shift is particularly important because conductors represent only one component of the total cost and value of a transmission project. Rights-of-way, permitting, towers, foundations, substations, engineering, construction, environmental mitigation and the time required to bring capacity into service can dwarf the incremental cost of selecting a higher-performing conductor.
ClearPath's modeling highlights this broader economic perspective. In its high-growth scenario, reconductoring reduces total transmission investment by approximately $20 billion, or about 30 percent, compared with a greenfield-only approach. Yet the study also finds that transmission itself remains a relatively modest portion of overall system investment. Across the modeled load-growth scenarios, bulk transmission expansion represents only 7–8 percent of total system investment through 2040, while enabling much larger investments in generation and supporting rapidly growing demand.
This is an important perspective for planners and regulators. Optimizing a conductor primarily around its purchase price can be a poor economic decision if doing so reduces the productive capacity of infrastructure that costs hundreds of millions - or billions - of dollars to permit and build.
Transmission should increasingly be evaluated in terms of lifetime infrastructure productivity: how much reliable, deliverable capacity a corridor provides; how quickly that capacity can become available; how efficiently electricity can be transported; how much future growth the design can accommodate; and how effectively the investment reduces the need for additional infrastructure later.
Twenty Years of Field Experience Matter
The growing recognition of composite-core conductors is also occurring at an important point in the technology's evolution. Advanced composite-core conductors are sometimes still discussed as though they are relatively new technologies awaiting large-scale validation. That characterization is increasingly difficult to reconcile with actual field experience.
At CTC Global
, ACCC® Conductor has now been deployed on more than 1,600 projects in 30 U.S. states and 70 countries. Over more than two decades, the technology has progressed from early development and qualification through large-scale commercial deployment across a broad range of voltages, climates, operating environments and project types.
The evolution has involved much more than simply replacing steel with a composite material. It has required advances in composite-core manufacturing, conductor design, purpose-built installation hardware, engineering practices, installation methods, testing protocols, manufacturing scale, international standards and field quality assurance. More recently, CTC Global has continued that progression through technologies such as InfoCore®, which supports conductor-core integrity verification, and GridVista™, which extends the role of the conductor itself by integrating fiber-based sensing capabilities that can provide greater visibility into transmission-system conditions.
These advances illustrate a broader point about innovation in critical infrastructure. A technology leap is important, but commercial maturity is created through continuous engineering, testing, standardization, manufacturing discipline and accumulated field experience. The transmission system is too important for innovation to be measured solely by novelty. It must ultimately be measured by demonstrated performance.
Better Technology Also Requires Better Planning Tools
Another particularly valuable contribution of the ClearPath/EER study is its focus on the tools used to make transmission decisions.
Historically, conductor selection often occurs relatively late in project development, after planners have already determined that a particular transmission project or upgrade is required. ClearPath argues that this sequencing can prevent advanced technologies from being properly evaluated because the capabilities of the conductor may fundamentally change which project represents the least-cost solution.
EER's proof-of-concept model attempts to address that problem by connecting long-term capacity-expansion modeling with detailed power-flow analysis. The model iterates between long-term planning and system reliability assessments so that reconductoring, greenfield construction and different conductor technologies can be considered as part of the optimization process rather than after the basic transmission decision has already been made.
This may ultimately be one of the report's most consequential ideas.
Advanced transmission technologies cannot deliver their full value if planning tools cannot recognize their capabilities. Better conductors, dynamic line ratings, topology optimization, advanced power-flow controls and other technologies increasingly require planning methods capable of comparing performance, timing, reliability and lifecycle value, rather than simply comparing equipment categories.
Recognizing the Limits - and the Opportunity
ClearPath is appropriately careful about the limitations of its analysis. The model does not contain detailed information about the age or structural condition of individual transmission assets, does not fully represent outage constraints associated with construction, and does not constrain the rate at which modeled transmission expansion can physically occur. It evaluates thermal limitations without fully modeling stability constraints, and it does not dynamically capture all of the electrical-loss implications associated with different reconductoring choices.
Those qualifications are important. This is a proof-of-concept planning study, not an engineering design for the ERCOT system.
But they do not diminish the larger lesson. If anything, they point toward the next stage of work: integrating better asset information, conductor-specific electrical characteristics, structural condition, losses, stability, construction schedules, outage requirements and other real-world considerations into increasingly sophisticated planning models.
The objective should not be to prove that one technology belongs everywhere. It should be to give planners the tools to determine where each technology creates the greatest system value.
A More Productive Way to Think About the Grid
The transmission system built over the next several decades will likely combine technologies and strategies that were once considered separately. New 500-kV and 765-kV backbones can provide enormous long-distance transfer capability and strengthen network topology. Reconductoring can unlock substantial additional capacity from existing corridors. Composite-core conductors can increase the productivity of both existing and new infrastructure. Emerging technologies may solve specialized constraints that conventional solutions cannot address economically.
The ClearPath analysis offers compelling quantitative support for this portfolio approach. It also reinforces an increasingly important engineering principle: the objective is not simply to build more transmission. It is to create more useful transmission capacity, more quickly and with greater lifetime value.
For those of us who have spent many years working to advance conductor technology, that is an encouraging development. The conversation is moving beyond whether advanced conductors deserve consideration. The more important questions now concern where they should be deployed, how their capabilities should influence system planning, and how much additional value they can help extract from every transmission corridor we already have - and every new one we build.
Congratulations to ClearPath, Casey Kelly and Will Bryant; Evolved Energy Research; Ryan Jones, Ben Preneta, Jeremy Hargreaves, Ben Haley, Alexandra von Meier and Jim Williams; and the many reviewers and contributors who supported this work. Their report adds meaningful analysis to an increasingly important discussion and provides another valuable step toward a transmission system designed not simply around what we have done before, but around what today's engineering and technology can now make possible.