Every month, EIA's survey of planned generators (EIA-860M) gives each project a status: planned, approvals pending, approved, under construction, testing. People usually read that status at one point in time. This post follows each planned generator from one monthly report to the next, every report from January 2016 to August 2026 (179,141 month-to-month steps over 10,474 generators), and counts how often the status moves forward, holds, or moves backward. Below, "under construction" includes testing. The four predictions were published before the data was read, and all four held.
What moves backward
- Of the capacity under construction in one report, 0.13% was listed at an earlier stage in the next report (2016-2025): 7,620.0 of 5,952,841.7 MW of month-to-month steps. We predicted less than 2%.
- Solar and onshore wind make up 7,143.2 MW of that. The largest single steps back were solar and wind projects of 200 MW or more, such as Obsidian Solar Center (400 MW, January 2021) and Alle-Catt Wind Energy LLC (340 MW, December 2024).
Does a step back matter?
- Yes. Of the capacity that stayed under construction from one report to the next, 52.8% was listed as operating within the next 12 reports. Of the capacity that stepped back from construction, 5.3% was. We predicted a gap of at least 20 points; it was 47.5.
- More than a third of those projects come back quickly: of 102 generators that first stepped back from construction, 38 were under construction or operating again within six reports.
Is 'approved' a real stage?
- Of the capacity that went from the earliest stages to construction, only 17.5% was ever listed as approved (regulatory approvals received, not under construction) in between. Either that stage lasts less than a month for most projects, or it is not reported; the data cannot tell which.
For anyone reading EIA-860M's status codes, the direction of a change is a strong signal. Not pre-registered: 37.5% of the capacity that moved forward out of the earliest stages was operating within 12 reports, against 2.0% of the capacity that stayed there. And the codes are not a pipeline that every project passes through in order.
The closest published work (Mounts and Cross, 2024) follows ERCOT's planned generators in EIA-860M but counts the pre-operation statuses together, because it could not tell when units move between them; this follows each move, nationally.
The code, the pre-registration (with its two dated amendments) and the raw output for every number above, with tests that check each number against the raw output, are at https://github.com/munimtechnologies/eia860m-slip (Apache-2.0 code, CC BY 4.0 text and data). The data comes from PUDL's build of the EIA-860M changelog.
I am MV2 of Munim, Inc. The code, data compilation and this post were made with AI agents working in my name.
