IRONWOOD
SubstationMichigan · NORTHERN STATES POWER CO - WISCONSIN
At a glance
IRONWOOD is an electric transmission substation in Michigan, on NORTHERN STATES POWER CO - WISCONSIN's transmission network. It is classified as sub-transmission (115 kv) and connects 5 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
Connected transmission lines
Lines terminating at or passing through this substation, by HIFLD line ID, highest voltage first.
| Line ID | Voltage | Owner | Status | Length |
|---|---|---|---|---|
| #109162 | 115 kV | NORTHERN STATES POWER CO - WISCONSIN | IN SERVICE | 1.5 mi |
| #117451 | 115 kV | NORTHERN STATES POWER CO - WISCONSIN | IN SERVICE | 1.9 mi |
| #173947 | — | NORTHERN STATES POWER CO - WISCONSIN | IN SERVICE | 2.1 mi |
| #173953 | — | NORTHERN STATES POWER CO - WISCONSIN | IN SERVICE | 10.0 mi |
| #173960 | — | NORTHERN STATES POWER CO - WISCONSIN | IN SERVICE | 18.5 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of IRONWOOD, 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 |
|---|---|---|---|---|---|---|---|
| OZ Gogebic | Greenfield | MI | Gogebic | — | — | 2.2 yrs | 59.7 |
| IRONWOOD | Substation-Adjacent | MI | Iron County | 115 kV | 100 MW | 2.2 yrs | 56.5 |
| NORRIE | Substation-Adjacent | MI | Iron County | 115 kV | 100 MW | 2.2 yrs | 56.4 |
| HURLEY | Substation-Adjacent | WI | Iron County | 115 kV | 100 MW | 4.3 yrs | 55.2 |
| UNKNOWN132506 | Substation-Adjacent | WI | Iron County | 115 kV | 100 MW | 4.3 yrs | 53.8 |
| EC FFE Gogebic County | Greenfield | MI | Gogebic County | — | — | 2.2 yrs | 51.3 |
| Mine Site | Former Mine | MI | Gogebic County | — | — | 2.2 yrs | 50.5 |
| Mine Site | Former Mine | MI | Gogebic County | — | — | 2.2 yrs | 50.5 |
How does IRONWOOD 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 IRONWOOD'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 IRONWOOD?
The 5 connected lines listed above are owned by NORTHERN STATES POWER CO - WISCONSIN. Line voltages range from 115 kV to 115 kV. Their combined recorded length is about 34.1 miles.
How do candidate sites near IRONWOOD score?
The 8 highest-scoring candidate sites within about 25 miles range from 51 to 60 on the 0–100 DC Readiness scale. They fall in Gogebic, Iron County, Gogebic 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 IRONWOOD substation?
IRONWOOD has a maximum voltage of 115 kV. That places it in the 115–229 kV band. The median named US substation in this dataset is 115 kV, so IRONWOOD is at the national midpoint.
How many transmission lines connect to IRONWOOD substation?
5 transmission lines terminate at or pass through IRONWOOD in the HIFLD line data. The connected lines listed here run at 115 kV. Together the listed lines cover about 34.1 miles.
Who owns IRONWOOD substation?
HIFLD does not publish substation owners directly. Most of the transmission lines that end at IRONWOOD belong to NORTHERN STATES POWER CO - WISCONSIN. GridCensus derives this from the line data, so confirm ownership with the utility for anything contractual.
Where is IRONWOOD substation located?
IRONWOOD is in Michigan at 46.4484, -90.1669. The datacenter candidate sites closest to it are in Gogebic, Iron County, Gogebic County.
Are there datacenter candidate sites near IRONWOOD substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of IRONWOOD. The highest-scoring is OZ Gogebic at 60/100. Across Michigan, the average DC Readiness score is 55.2.
Other 115 kV substations in Michigan
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, “IRONWOOD substation, Michigan”, https://gridcensus.com/substations/michigan/ironwood-37c4703b (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 IRONWOOD 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.