TAP139402
SubstationIllinois · AMEREN ILLINOIS COMPANY
At a glance
TAP139402 is an electric transmission substation in Illinois, on AMEREN ILLINOIS COMPANY's transmission network. It is classified as sub-transmission (138 kv) and connects 3 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
Connected transmission lines
Lines terminating at or passing through this substation, by HIFLD line ID, highest voltage first.
| Line ID | Voltage | Owner | Status | Length |
|---|---|---|---|---|
| #104870 | 138 kV | AMEREN ILLINOIS COMPANY | IN SERVICE | 0.0 mi |
| #145680 | 138 kV | AMEREN ILLINOIS COMPANY | IN SERVICE | 15.9 mi |
| #176004 | 138 kV | AMEREN ILLINOIS COMPANY | IN SERVICE | 2.1 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of TAP139402, 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 |
|---|---|---|---|---|---|---|---|
| COFFEEN | Substation-Adjacent | IL | Bond County | 345 kV | 600 MW | 4.8 yrs | 65.8 |
| UNKNOWN122158 | Substation-Adjacent | IL | Shelby County | 345 kV | 600 MW | 4.8 yrs | 60.9 |
| RAMSEY | Substation-Adjacent | IL | Fayette County | 345 kV | 600 MW | 4.8 yrs | 60.4 |
| EC FFE Marion County | Greenfield | IL | Marion County | — | — | 4.8 yrs | 58.7 |
| EC Coal Montgomery County | Greenfield | IL | Montgomery County | — | — | 4.8 yrs | 57.9 |
| OZ Bond | Greenfield | IL | Bond | — | — | 4.8 yrs | 57.1 |
| OZ Fayette | Greenfield | IL | Fayette | — | — | 4.8 yrs | 57.0 |
| EC Near Coffeen | Greenfield | IL | Montgomery | — | — | 4.8 yrs | 56.7 |
Who owns the transmission lines at TAP139402?
The 3 connected lines listed above are owned by AMEREN ILLINOIS COMPANY. Line voltages range from 138 kV to 138 kV. Their combined recorded length is about 17.9 miles.
How do candidate sites near TAP139402 score?
The 8 highest-scoring candidate sites within about 25 miles range from 57 to 66 on the 0–100 DC Readiness scale. They fall in Bond County, Shelby County, Fayette County, Marion County. The Illinois average across 3,641 scored sites is 54.3. 795 of those Illinois sites are classed as substation sites (candidate locations generated at an existing substation).
Frequently asked questions
What voltage is TAP139402 substation?
TAP139402 has a maximum voltage of 138 kV. That places it in the 115–229 kV band. The median named US substation in this dataset is 115 kV, so TAP139402 is above the national midpoint.
How many transmission lines connect to TAP139402 substation?
3 transmission lines terminate at or pass through TAP139402 in the HIFLD line data. The connected lines listed here run at 138 kV. Together the listed lines cover about 17.9 miles.
Who owns TAP139402 substation?
HIFLD does not publish substation owners directly. Most of the transmission lines that end at TAP139402 belong to AMEREN ILLINOIS COMPANY. GridCensus derives this from the line data, so confirm ownership with the utility for anything contractual.
Where is TAP139402 substation located?
TAP139402 is in Illinois at 38.9897, -89.0085. The datacenter candidate sites closest to it are in Bond County, Shelby County, Fayette County.
Are there datacenter candidate sites near TAP139402 substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of TAP139402. The highest-scoring is COFFEEN at 66/100. Across Illinois, the average DC Readiness score is 54.3.
More in Illinois
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, “TAP139402 substation, Illinois”, https://gridcensus.com/substations/illinois/tap139402-f3d4d77d (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 TAP139402 substation, Illinois 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.