On February 17, 2022, FERC launched an inquiry to examine whether the use of dynamic line ratings would improve the accuracy and transparency of transmission line ratings.
Transmission line ratings represent the maximum transfer capability of each transmission line. The use of dynamic line ratings, which are based on a wide range of weather and line-specific factors affecting the operation of transmission lines, would build upon Order No. 881’s direction to use ambient-adjusted ratings, which include forecasted ambient air temperature and the presence of solar heating (see December 22, 2021 edition of the WER). In Order No. 881, FERC determined that static transmission line ratings can cause transmission providers to either understate or overstate transmission capability. Chairman Glick remarked, “[i]f we are going to meet the needs of the grid of the future while keeping customer rates just and reasonable and maintaining grid reliability, we need to squeeze everything out of our existing grid.” Glick also noted that Order No. 881 was a “huge step forward in making more efficient use of our transmission system and saving money for customers. But our work isn’t done. I look forward to working with my colleagues to explore the adoption of dynamic line ratings to further increase the efficiency of our grid.”
FERC’s Notice of Inquiry seeks to evaluate the relative benefits, costs and challenges associated with a dynamic line rating implementation. In particular, FERC asks whether the lack of dynamic line rating requirements render current wholesale rates unjust and unreasonable and to discuss potential criteria for dynamic line rating requirements.
Initial comments are due 60 days after publication in the Federal Register, with reply comments due 30 days later.
A copy of the notice is available here.