NORTH LOOP
SubstationArizona
At a glance
NORTH LOOP is an electric transmission substation in Arizona. It is classified as sub-transmission (138 kv) and connects 8 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
No owner is recorded for the lines that connect here.
Connected transmission lines
Lines terminating at or passing through this substation, by HIFLD line ID, highest voltage first.
| Line ID | Voltage | Owner | Status | Length |
|---|---|---|---|---|
| #302746 | 138 kV | — | IN SERVICE | 11.4 mi |
| #303699 | 138 kV | — | IN SERVICE | 13.7 mi |
| #306706 | 138 kV | — | IN SERVICE | 14.5 mi |
| #308409 | 138 kV | — | IN SERVICE | 10.9 mi |
| #309046 | 138 kV | — | IN SERVICE | 6.0 mi |
| #309548 | 138 kV | — | IN SERVICE | 14.5 mi |
| #312197 | 138 kV | — | IN SERVICE | 14.5 mi |
| #313088 | 138 kV | — | IN SERVICE | 14.5 mi |
Nearby datacenter candidate sites
Scored candidate sites within roughly 25 miles of NORTH LOOP, 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 |
|---|---|---|---|---|---|---|---|
| SAGUARO | Substation-Adjacent | AZ | Pinal County | 500 kV | 1,000 MW | 3.5 yrs | 63.8 |
| Tucson International Airport Area | Brownfield | AZ | Pima | 230 kV | 3 MW | 3.5 yrs | 62.9 |
| OZ Pima | Greenfield | AZ | Pima | — | — | 3.5 yrs | 62.8 |
| TUCSON | Substation-Adjacent | AZ | Pima County | 345 kV | 600 MW | 3.5 yrs | 62.7 |
| OZ Pima | Greenfield | AZ | Pima | — | — | 3.5 yrs | 62.4 |
| TORTOLITA | Substation-Adjacent | AZ | Pinal County | 500 kV | 1,000 MW | 3.5 yrs | 62.0 |
| IRVINGTON | Substation-Adjacent | AZ | Santa Cruz County | 230 kV | 300 MW | 3.5 yrs | 61.7 |
| OZ Pima | Greenfield | AZ | Pima | — | — | 3.5 yrs | 61.6 |
How does NORTH LOOP compare with other substations in Arizona?
Arizona has 892 substation records in HIFLD, of which 466 carry a station name; the rest are unnamed tap points, risers and line ends. 87 named substations in the state are in NORTH LOOP's 115–229 kV band (19% of named stations). 138 sit in a higher band. 47 named substations in Arizona operate at 345 kV or above. The highest voltage recorded in the state is 500 kV, and the state median is 69 kV.
How do candidate sites near NORTH LOOP score?
The 8 highest-scoring candidate sites within about 25 miles range from 62 to 64 on the 0–100 DC Readiness scale. They fall in Pinal County, Pima, Pima County, Santa Cruz County. The Arizona average across 3,816 scored sites is 48.5. 614 of those Arizona sites are classed as substation sites (candidate locations generated at an existing substation).
Frequently asked questions
What voltage is NORTH LOOP substation?
NORTH LOOP 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 NORTH LOOP is above the national midpoint.
How many transmission lines connect to NORTH LOOP substation?
8 transmission lines terminate at or pass through NORTH LOOP in the HIFLD line data. The connected lines listed here run at 138 kV. Together the listed lines cover about 100.2 miles.
Where is NORTH LOOP substation located?
NORTH LOOP is in Arizona at 32.4011, -111.1263. The datacenter candidate sites closest to it are in Pinal County, Pima, Pima County.
Are there datacenter candidate sites near NORTH LOOP substation?
GridCensus lists at least 8 scored candidate sites within roughly 25 miles of NORTH LOOP. The highest-scoring is SAGUARO at 64/100. Across Arizona, the average DC Readiness score is 48.5.
Other 138 kV substations in Arizona
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, “NORTH LOOP substation, Arizona”, https://gridcensus.com/substations/arizona/north-loop-44079998 (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 NORTH LOOP substation, Arizona 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.