Upgrading Existing Power Lines Could Rapidly Expand Grid Capacity

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The author argues that upgrading existing power lines with advanced conductor technology could significantly expand the U.S. transmission grid's capacity much faster and at lower cost than building new transmission lines. While permitting reform is needed to speed up new transmission projects, upgrading existing infrastructure by reconductoring could deliver large capacity increases in the near-term without the same permitting challenges.

Why it matters

Rapidly increasing electricity demand from new technologies like data centers, electric vehicles, and electrified industry is outpacing the ability to build new transmission lines. Upgrading existing transmission corridors with advanced conductors could provide a faster and more cost-effective way to expand grid capacity and meet growing demand.

The details

The author, who has over 20 years of experience in the transmission sector, explains that thousands of miles of high-voltage transmission lines in the U.S. were built with outdated steel-core aluminum conductors that limit their capacity. Upgrading these lines with modern composite-core conductors can increase their capacity by 50-75% or even double the original rating, often without needing to replace towers or expand corridors. This "advanced reconductoring" can be completed in 1-2 construction seasons, avoiding years of permitting and routing disputes required for new transmission lines.

• The Energy Institute at Haas at UC Berkeley published research in 2024 on the benefits of advanced reconductoring.

What’s next

Policymakers and regulators will need to ensure that utilities are incentivized to pursue capital-efficient upgrades like advanced reconductoring, rather than just being rewarded for large capital investments in new transmission lines.