Steel For Fuel N° 021 of 56 4 Sep 2024
Where have all the transmission lines gone?
by Andy Lubershane, Partner and Head of Research, Energy Impact Partners
In this note
The question
With new US transmission stalled, how much can technology make up the difference?
The answer
Some of it, not all. He is increasingly confident the sector must squeeze more out of existing lines, and sees real traction there. But he stands by an earlier conclusion: transmission expansion is still, ultimately, more a collective action problem for governments and citizens than a puzzle for technologists.
03The argument
The first chart, from Grid Strategies, records the slowdown in US transmission construction through the 2020s; its numbers sit in the image, so this note carries his reading rather than the data. He calls it probably the most concerning trend for the pace of the American energy transition, because bigger, longer lines have become increasingly critical for unlocking renewable resources; their deployment should be accelerating, not slowing. Since it is not, he turns to the lines already standing. Dynamic line rating is his example: a line’s static capacity is set by the most adverse conditions it might meet in a season, or in some cases ever, while continuous measurement lets an operator lift that limit when conditions allow. Then the caveat: these tools, and advanced conductors, run into technical detail and regulatory thickets, and he warns that people who do not operate grids are easily charmed by elegant solutions that turn messy in practice. Which is why his closing ask is political, not technical.
04What you need to know first
- Dynamic line rating
- Setting a line’s capacity from real operating conditions rather than a fixed worst-case weather rating.
- Grid enhancing technologies
- Once called smart grid technology: sensing, monitoring and control that lift existing corridors’ capacity.
05Details worth keeping
- The opening chart is Grid Strategies’ “Fewer new miles”, July 2024.
- He names LineVision, Prisma Photonics and Ampacimon on dynamic line rating, and TS Conductor on advanced conductors.
- He points to a bipartisan permitting bill from Senators Manchin and Barraso (his spelling), and suggests US readers might consider calling their congressperson.
06Claims worth citing
All figures as stated on 2024-09-04.
- In one pilot of 42 sensors on five lines, dynamic line rating raised the highest-voltage line’s average summer capacity by over 25%. AES and LineVision study, April 2024, cited by Lubershane
- Federal Energy Regulatory Commission Order 1977 asserts the agency’s backstop siting authority in a small number of designated National Interest Electric Transmission Corridors. Lubershane
07Where it’s contested
Nobody argues back; the hedges are his own. He is only cautiously optimistic about the recent regulatory activity. He reaffirms rather than revises: the collective action conclusion he stands by is the assumption the technology half of the post never tests.