BUTTERNUT
SubstationWisconsin · AMERICAN TRANSMISSION CO
BUTTERNUT is an electric transmission substation in Wisconsin, operated by AMERICAN TRANSMISSION CO. 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 |
|---|---|---|---|---|
| #28835 | 138 kV | AMERICAN TRANSMISSION CO | IN SERVICE | 13.0 mi |
| #33702 | 138 kV | AMERICAN TRANSMISSION CO | IN SERVICE | 4.0 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of BUTTERNUT, 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 |
|---|---|---|---|---|---|---|---|
| FITZGERALD | Substation-Adjacent | WI | Winnebago County | 345 kV | 600 MW | 1.4 yrs | 72.3 |
| MARTIN ROAD | Substation-Adjacent | WI | Fond du Lac County | 138 kV | 100 MW | 1.4 yrs | 72.0 |
| CYPRESS | Substation-Adjacent | WI | Calumet County | 345 kV | 600 MW | 1.4 yrs | 71.5 |
| SOUTH FOND DE LAC | Substation-Adjacent | WI | Fond du Lac County | 345 kV | 600 MW | 1.4 yrs | 70.5 |
| RIENZI | Substation-Adjacent | WI | Fond du Lac County | 138 kV | 100 MW | 1.4 yrs | 69.2 |
| TAP138062 | Substation-Adjacent | WI | Washington County | 345 kV | 600 MW | 1.4 yrs | 69.1 |
| Greenfield (SOUTH FOND DE LAC - FITZGERALD) | Greenfield | WI | Fond du Lac County | 345 kV | 600 MW | 1.4 yrs | 69.0 |
| Greenfield (FOREST JUNCTION - CYPRESS) | Greenfield | WI | Calumet County | 345 kV | 600 MW | 1.4 yrs | 69.0 |
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
This page shows a public slice of the GridCensus dataset for BUTTERNUT substation, Wisconsin. Pro and Enterprise plans unlock the full 164,098-site catalog, raw sub-scores, parcel ownership, interconnection-queue detail, saved searches, and programmatic API access.