Insight note · 1 November 2026

Transformer lead times: what a comparable figure states, and what published figures often leave out

Published lead-time figures for the same year and class of transformer can sit more than ten times apart. Two figures can be compared only when each says what it counts.

Anvilmore Research Team

Illustration: A large power transformer core and its copper windings standing uncased on a factory floor, laminated steel core visible, a long run of thick copper busbar leading in from the left.

Figures as of 30 October 2026.

A transformer lead time usually arrives as one figure, in a quote, an offer or a news release. Before anyone plans around it, the useful question is what that figure measures. This note draws on 38 dated transformer lead-time figures compiled for this research from 19 public documents. For the same year and broad class, they sit anywhere from about 3% apart, for one benchmark's generator step-up pair, to more than ten times apart across sources (our arithmetic). In the pairs set out below, the sources' own wording shows they differ on, or leave unstated, where the clock starts and stops, which statistic is given, which class, and which market.

One year, three figures

In February 2022 the US Department of Energy (DOE) reported a stakeholder average of 12 to 16 weeks to manufacture a large power transformer, "if all the materials are available" [1]. The report lists testing, shipping preparation, transport and the last miles to site as separate stages, so this figure counts the build alone. In July 2022 a utility consultant told T&D World that a large transformer could once be ordered in under a year, and that one relatively large US manufacturer was at about 38 months [2]. In December 2022 DOE's Office of Policy said the average time to receive a new large power transformer is "often more than two years" [3]. Neither of the later figures says when its clock starts.

A later pair differs on several points at once

Wood Mackenzie's benchmark, in a US-focused report with American Clean Power from September 2025, gives a second-quarter 2025 average of 128.0 weeks "ARO" for power transformers [4]. The report does not spell out the term or say where the count ends. In February 2025 the International Energy Agency (IEA) said it can take "up to four years" to secure a large power transformer, a global maximum with no stated start [5]. The gap is about 1.6 times, but it mixes clock, statistic and geography, and the record does not allow it to be split among them.

One definition, one class: the closest pair

The same benchmark put generator step-up transformers at 147.7 and 143.4 weeks ARO in the first and second quarters of 2025 [4]. Class still matters at that level: in the second quarter, pad-mount distribution transformers averaged 24.0 weeks single-phase and 46.4 weeks three-phase, close to double (our arithmetic) [4].

Most figures state one end of the clock or neither

Of the 38 figures, 7 state both ends of the clock and 16 state neither. Careful sources can blur the terms too. DOE's July 2024 report to Congress, drawing on interviews in June 2023, calls 36-month lead times "acquisition" lead times on one page and discusses them under "manufacturing lead times" on another [6].

What a comparable figure states

On this evidence, a lead-time figure can be compared with another, or planned against, when it states five things. It names when the clock starts and when it stops, and the class, with the sub-class where that matters. It says whether it is an average, a commonly quoted figure or a maximum, which market it describes, and which date. A figure without them may still be accurate. It cannot be set beside another figure, and a gap between two such figures cannot show which one is right, so a shorter quoted figure is not yet evidence of an earlier date.

Related: US transformer prices showed the 2021 squeeze as it happened, but not its peak or its easing

Sources

  1. Electric Grid Supply Chain Review: Large Power Transformers and High Voltage Direct Current Systems, US Department of Energy, 24 February 2022, printed pp. 21 and 53. https://www.energy.gov/sites/default/files/2022-02/Electric%20Grid%20Supply%20Chain%20Report%20-%20Final.pdf
  2. Transformative Times: Update on the U.S. Transformer Supply Chain, T&D World, 12 July 2022 (secondary; quotes a utility consultant). https://www.tdworld.com/utility-business/article/21243198/transformative-times-update-on-the-us-transformer-supply-chain
  3. The Supply Chain Crisis Facing the Nation's Electric Grid, US Department of Energy Office of Policy, 12 December 2022, p. 1. https://www.energy.gov/sites/default/files/2022-12/The%20Supply%20Chain%20Crisis%20Facing%20the%20Nations%20Electric%20Grid_12.12.22.pdf
  4. Making the connection: meeting the electric T&D supply chain challenge, Executive Summary, Wood Mackenzie with American Clean Power, September 2025, p. 5 (copy hosted by POWER magazine). https://www.powermag.com/wp-content/uploads/2026/01/making-the-connection-executive-summary-september-2025.pdf
  5. Building the Future Transmission Grid: Executive summary, International Energy Agency, February 2025. https://www.iea.org/reports/building-the-future-transmission-grid/executive-summary
  6. Large Power Transformer Resilience: Report to Congress, US Department of Energy, July 2024, pp. 2 and 12. https://www.energy.gov/sites/default/files/2024-10/EXEC-2022-001242%20-%20Large%20Power%20Transformer%20Resilience%20Report%207-10-24.pdf