KNOB
SubstationCalifornia · IMPERIAL IRRIGATION DISTRICT
At a glance
KNOB is an electric transmission substation in California, on IMPERIAL IRRIGATION DISTRICT'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
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 |
|---|---|---|---|---|
| #304920 | 230 kV | IMPERIAL IRRIGATION DISTRICT | IN SERVICE | 21.7 mi |
| #311848 | 161 kV | — | IN SERVICE | 20.3 mi |
| #313170 | 161 kV | IMPERIAL IRRIGATION DISTRICT | IN SERVICE | 3.2 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of KNOB, 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 |
|---|---|---|---|---|---|---|---|
| NORTH GILA | Substation-Adjacent | AZ | Yuma County | 500 kV | 1,000 MW | 3.5 yrs | 60.1 |
| OZ Yuma | Greenfield | AZ | Yuma | — | — | 3.5 yrs | 58.4 |
| OZ Yuma | Greenfield | AZ | Yuma | — | — | 3.5 yrs | 57.8 |
| OZ Yuma | Greenfield | AZ | Yuma | — | — | 3.5 yrs | 55.8 |
| OZ Yuma | Greenfield | AZ | Yuma | — | — | 3.5 yrs | 55.5 |
| OZ Yuma | Greenfield | AZ | Yuma | — | — | 3.5 yrs | 53.9 |
| GILA | Substation-Adjacent | AZ | Yuma County | 161 kV | 100 MW | 3.5 yrs | 52.4 |
| DOME TAP | Substation-Adjacent | AZ | Yuma County | 161 kV | 100 MW | 3.5 yrs | 52.3 |
How does KNOB compare with other substations in California?
California has 4,260 substation records in HIFLD, of which 3,003 carry a station name; the rest are unnamed tap points, risers and line ends. 697 named substations in the state are in KNOB's 115–229 kV band (23% of named stations). 428 sit in a higher band. 44 named substations in California operate at 345 kV or above. The highest voltage recorded in the state is 500 kV, and the state median is 69 kV.
Who owns the transmission lines at KNOB?
The 3 connected lines listed above are owned by IMPERIAL IRRIGATION DISTRICT. Line voltages range from 161 kV to 230 kV. Their combined recorded length is about 45.3 miles.
How do candidate sites near KNOB score?
The 8 highest-scoring candidate sites within about 25 miles range from 52 to 60 on the 0–100 DC Readiness scale. They fall in Yuma County, Yuma. The California average across 8,490 scored sites is 45.4. 1,573 of those California sites are classed as substation sites (candidate locations generated at an existing substation).
Frequently asked questions
What voltage is KNOB substation?
KNOB has a maximum voltage of 161 kV. That places it in the 115–229 kV band. The median named US substation in this dataset is 115 kV, so KNOB is above the national midpoint.
How many transmission lines connect to KNOB substation?
3 transmission lines terminate at or pass through KNOB in the HIFLD line data. The connected lines listed here run at 230 kV, 161 kV. Together the listed lines cover about 45.3 miles.
Who owns KNOB substation?
HIFLD does not publish substation owners directly. Most of the transmission lines that end at KNOB belong to IMPERIAL IRRIGATION DISTRICT. GridCensus derives this from the line data, so confirm ownership with the utility for anything contractual.
Where is KNOB substation located?
KNOB is in California at 32.7604, -114.7486. The datacenter candidate sites closest to it are in Yuma County, Yuma.
Are there datacenter candidate sites near KNOB substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of KNOB. The highest-scoring is NORTH GILA at 60/100. Across California, the average DC Readiness score is 45.4.
Other 161 kV substations in California
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, “KNOB substation, California”, https://gridcensus.com/substations/california/knob-31005c33 (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 KNOB substation, California 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.