BIG STONE SOUTH
SubstationSouth Dakota · OTTER TAIL COMPANY
BIG STONE SOUTH is an electric transmission substation in South Dakota, operated by OTTER TAIL COMPANY. It is classified as high-voltage (345 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
Connected transmission lines
Lines terminating at or passing through this substation, by HIFLD line ID, highest voltage first.
| Line ID | Voltage | Owner | Status | Length |
|---|---|---|---|---|
| #65902 | 345 kV | OTTER TAIL COMPANY | IN SERVICE | 30.4 mi |
| #65910 | 345 kV | — | — | 31.0 mi |
| #65911 | 230 kV | — | — | 0.2 mi |
| #65918 | 230 kV | — | — | 1.7 mi |
| #65920 | 230 kV | — | — | 1.6 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of BIG STONE SOUTH, 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 |
|---|---|---|---|---|---|---|---|
| BIG STONE SOUTH | Substation-Adjacent | SD | Grant County | 345 kV | 600 MW | 1.0 yrs | 71.5 |
| UNKNOWN131144 | Substation-Adjacent | MN | Big Stone County | 230 kV | 300 MW | 1.0 yrs | 69.9 |
| UNKNOWN175846 | Substation-Adjacent | SD | Grant County | 345 kV | 600 MW | 1.0 yrs | 69.8 |
| UNKNOWN175849 | Substation-Adjacent | MN | Big Stone County | 345 kV | 600 MW | 1.0 yrs | 69.5 |
| BIG STONE | Substation-Adjacent | SD | Grant County | 230 kV | 300 MW | 1.0 yrs | 69.3 |
| UNKNOWN175855 | Substation-Adjacent | SD | Grant County | 230 kV | 300 MW | 1.0 yrs | 69.1 |
| UNKNOWN175856 | Substation-Adjacent | SD | Codington County | 230 kV | 300 MW | 1.0 yrs | 67.0 |
| Greenfield (UNKNOWN175846 - UNKNOWN175847) | Greenfield | SD | Deuel County | 345 kV | 600 MW | 1.0 yrs | 66.1 |
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 BIG STONE SOUTH substation, South Dakota. 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.