TAP209866
SubstationMontana
At a glance
TAP209866 is an electric transmission substation in Montana. It is classified as distribution (69–115 kv) and connects 2 transmission lines. Substation proximity is one of the strongest speed-to-power signals for siting a datacenter — interconnection distance to an energized, high-voltage bus is often the binding constraint on time-to-energization.
Voltage & classification
Ownership
No owner is recorded for the lines that connect here.
Connected transmission lines
Lines terminating at or passing through this substation, by HIFLD line ID, highest voltage first.
| Line ID | Voltage | Owner | Status | Length |
|---|---|---|---|---|
| #212242 | 69 kV | — | IN SERVICE | 1.4 mi |
| #212243 | 69 kV | — | IN SERVICE | 1.6 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of TAP209866, ranked by DC Readiness. Sites this close to an energized substation carry a strong speed-to-power advantage.
| Site | Type | State | County | Voltage | Capacity | Queue wait | Score |
|---|---|---|---|---|---|---|---|
| EC Near Colstrip | Greenfield | MT | Rosebud | — | — | 1.1 yrs | 65.7 |
| EC Near Colstrip | Greenfield | MT | Rosebud | — | — | 1.1 yrs | 64.9 |
| UNKNOWN205569 | Substation-Adjacent | MT | Rosebud County | 115 kV | 100 MW | 1.1 yrs | 63.9 |
| EC Near Colstrip | Greenfield | MT | Rosebud | — | — | 1.1 yrs | 62.7 |
| TAP206859 | Substation-Adjacent | MT | Rosebud County | 115 kV | 100 MW | 1.1 yrs | 62.1 |
| UNKNOWN206861 | Substation-Adjacent | MT | Rosebud County | 115 kV | 100 MW | 1.1 yrs | 62.1 |
| OZ Big Horn | Greenfield | MT | Big Horn | — | — | 1.1 yrs | 60.9 |
| UNKNOWN205574 | Substation-Adjacent | MT | Treasure County | 115 kV | 100 MW | 1.1 yrs | 59.9 |
How do candidate sites near TAP209866 score?
The 8 highest-scoring candidate sites within about 25 miles range from 60 to 66 on the 0–100 DC Readiness scale. They fall in Rosebud, Rosebud County, Big Horn, Treasure County. The Montana average across 2,542 scored sites is 54.3. 815 of those Montana sites are classed as substation sites (candidate locations generated at an existing substation).
Frequently asked questions
What voltage is TAP209866 substation?
TAP209866 has a maximum voltage of 69 kV. That places it in the 69–114 kV band. The median named US substation in this dataset is 115 kV, so TAP209866 is below the national midpoint.
How many transmission lines connect to TAP209866 substation?
2 transmission lines terminate at or pass through TAP209866 in the HIFLD line data. The connected lines listed here run at 69 kV. Together the listed lines cover about 3 miles.
Where is TAP209866 substation located?
TAP209866 is in Montana at 45.7936, -107.0559. The datacenter candidate sites closest to it are in Rosebud, Rosebud County, Big Horn.
Are there datacenter candidate sites near TAP209866 substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of TAP209866. The highest-scoring is EC Near Colstrip at 66/100. Across Montana, the average DC Readiness score is 54.3.
More in Montana
About this data
Source: HIFLD Electric Substations and Transmission Lines (U.S. Department of Homeland Security), as published June 29, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: GridCensus, “TAP209866 substation, Montana”, https://gridcensus.com/substations/montana/tap209866-f82ceefc (data as of June 29, 2026).
Dataset updated . Screening estimates derived from public data sources.
Substation attributes are derived from public HIFLD / EIA infrastructure data and may lag real-world upgrades or retirements. Voltage and connected-line counts are screening figures — confirm available capacity and interconnection terms directly with the operating utility and ISO.
Go deeper than the public screen
Every site and score for TAP209866 substation, Montana is free to browse. Pro adds Watchtower on 25 sites, alerts when new candidate sites, datacenters or interconnection-queue requests appear in your markets, score and capacity history, and CSV export. Enterprise adds team seats, weekly data files for all 147,272 sites, the REST API and an MCP server for AI tools.