AEP COLBY
SubstationMichigan · INDIANA MICHIGAN POWER CO
At a glance
AEP COLBY is an electric transmission substation in Michigan, on INDIANA MICHIGAN POWER CO's transmission network. It is classified as sub-transmission (138 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
Connected transmission lines
Lines terminating at or passing through this substation, by HIFLD line ID, highest voltage first.
| Line ID | Voltage | Owner | Status | Length |
|---|---|---|---|---|
| #120214 | 138 kV | — | IN SERVICE | 0.1 mi |
| #131479 | 138 kV | INDIANA MICHIGAN POWER CO | IN SERVICE | 11.2 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of AEP COLBY, 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 |
|---|---|---|---|---|---|---|---|
| OLIVE | Substation-Adjacent | IN | St. Joseph County | 345 kV | 600 MW | 3.0 yrs | 70.9 |
| WEEDS LAKE | Substation-Adjacent | MI | Kalamazoo County | 345 kV | 600 MW | 2.2 yrs | 68.8 |
| KENZIE CREEK | Substation-Adjacent | MI | Cass County | 345 kV | 600 MW | 2.2 yrs | 68.4 |
| JACKSON ROAD | Substation-Adjacent | IN | St. Joseph County | 345 kV | 600 MW | 3.0 yrs | 67.0 |
| TAP138974 | Substation-Adjacent | IN | Elkhart County | 345 kV | 600 MW | 3.0 yrs | 66.7 |
| BENTON HARBOR | Substation-Adjacent | MI | Van Buren County | 345 kV | 600 MW | 2.2 yrs | 66.1 |
| TWIN BRANCH (345 KV) | Substation-Adjacent | IN | St. Joseph County | 345 kV | 600 MW | 3.0 yrs | 66.0 |
| UNKNOWN122939 | Substation-Adjacent | IN | Elkhart County | 345 kV | 600 MW | 3.0 yrs | 65.9 |
How does AEP COLBY compare with other substations in Michigan?
Michigan has 1,880 substation records in HIFLD, of which 277 carry a station name; the rest are unnamed tap points, risers and line ends. 106 named substations in the state are in AEP COLBY's 115–229 kV band (38% of named stations). 44 sit in a higher band. 43 named substations in Michigan operate at 345 kV or above. The highest voltage recorded in the state is 765 kV, and the state median is 138 kV.
Who owns the transmission lines at AEP COLBY?
The 2 connected lines listed above are owned by INDIANA MICHIGAN POWER CO. Line voltages range from 138 kV to 138 kV. Their combined recorded length is about 11.3 miles.
How do candidate sites near AEP COLBY score?
The 8 highest-scoring candidate sites within about 25 miles range from 66 to 71 on the 0–100 DC Readiness scale. They fall in St. Joseph County, Kalamazoo County, Cass County, Elkhart County. The Michigan average across 5,157 scored sites is 55.2. 768 of those Michigan sites are classed as substation sites (candidate locations generated at an existing substation).
Frequently asked questions
What voltage is AEP COLBY substation?
AEP COLBY 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 AEP COLBY is above the national midpoint.
How many transmission lines connect to AEP COLBY substation?
2 transmission lines terminate at or pass through AEP COLBY in the HIFLD line data. The connected lines listed here run at 138 kV. Together the listed lines cover about 11.3 miles.
Who owns AEP COLBY substation?
HIFLD does not publish substation owners directly. Most of the transmission lines that end at AEP COLBY belong to INDIANA MICHIGAN POWER CO. GridCensus derives this from the line data, so confirm ownership with the utility for anything contractual.
Where is AEP COLBY substation located?
AEP COLBY is in Michigan at 41.9973, -86.0911. The datacenter candidate sites closest to it are in St. Joseph County, Kalamazoo County, Cass County.
Are there datacenter candidate sites near AEP COLBY substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of AEP COLBY. The highest-scoring is OLIVE at 71/100. Across Michigan, the average DC Readiness score is 55.2.
Other 138 kV substations in Michigan
- JACKSON· 14 lines
- VERONA· 11 lines
- DELHI· 10 lines
- BEECHER· 9 lines
- CHANDLER· 9 lines
- WEADOCK· 9 lines
- PRESQUE ISLE STATION· 8 lines
- BLACK RIVER· 7 lines
- All named substations in Michigan· 277 stations
- Datacenter candidate sites in Michigan· 5,157 sites
- Brownfield and retired plant sites in Michigan
- Substations by state
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, “AEP COLBY substation, Michigan”, https://gridcensus.com/substations/michigan/aep-colby-c02a5e18 (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 AEP COLBY substation, Michigan 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.