San Antonio / Austin.
Seventy-two data centers make San Antonio the workhorse of Texas colocation, anchored by a ~505 MW hyperscale cluster at Westover Hills. An hour north, Williamson County — Round Rock, Hutto, Taylor — is sprinting toward 1.6–1.9 GW at full buildout beside Samsung's fab, and a 1.2 GW gas-supplied AI campus is rising between New Braunfels and San Marcos.
The market right now
The corridor's signature is behind-the-meter power: CloudBurst's Energy Transfer gas deal, Calpine's powered land beside its own plant, on-site generation planned at Jarrell. CPS Energy is spending over a billion dollars on transmission for the load it can serve. Federal OSHA jurisdiction and a single statewide TDLR license make this the simplest regulatory picture of any major market — the hazards, not the paperwork, are the story.
- San Antonio hosts 72 data centers from 17 providers; 15th-largest US market with power capacity up 150% since 2022 (Baxtel, 2026)
- Microsoft is the market's largest operator: 19 San Antonio-area facilities, ~505 MW operational, plus a $482M Castroville project announced July 2024 (Baxtel 2026; DCD 2024)
- Williamson County (Round Rock/Hutto/Taylor/Georgetown) has 8 operating data centers (~500 MW) and ~30 built or planned across 9 campuses; 1.6-1.9 GW at full buildout (Austin Free Press, 2026)
- CloudBurst broke ground on a 1.2 GW AI campus near New Braunfels/San Marcos, supplied under a natural gas agreement with Energy Transfer (Energy Transfer / w.media, 2025)
- CPS Energy plans upwards of $1.3B in transmission and generation over five years to serve data center growth (DCD, 2024)
- Skybox's Hutto campus is planned for 600 MW and $10B+ at full buildout (Austin Free Press, 2026)
Every campus on the map
Solid copper markers are operating campuses; white markers are under construction; dashed outlines are announced or planned. Locations are approximate campus-level centroids compiled from public sources — county records, operator announcements, and market reports — as of August 2026. Dense clusters are grouped. Corrections are welcome through the contact page.
Operating campuses mapped
- Microsoft Westover Hills cluster — Microsoft · West San Antonio. 14 operational buildings, ~505 MW; largest is SAT81 at 50 MW (Baxtel, 2026)
- CyrusOne San Antonio — CyrusOne · West San Antonio. 8 operational facilities, ~142 MW (Baxtel, 2026)
- Vantage San Antonio — Vantage Data Centers · West San Antonio. Two operational buildings, ~72 MW (Baxtel, 2026)
- QTS San Antonio — QTS · Northwest San Antonio. ~338,700 sq ft mega data center, ~45 MW (Baxtel, 2026)
- H5 100 Taylor — H5 Data Centers · Downtown San Antonio. Downtown carrier hotel / colo (Baxtel, 2026)
- Switch Round Rock — Switch · Round Rock. Two operational data centers serving the Dell ecosystem (Austin Free Press, 2026)
- Sabey Round Rock — Sabey Data Centers · Round Rock. Operational campus hosting UT Austin's Horizon research supercomputer (Austin Free Press, 2026)
- Skybox Hutto — Skybox Datacenters · Hutto. Two buildings operating; 600 MW / $10B+ planned at full buildout (Austin Free Press, 2026)
Under construction & planned
- Microsoft SA expansion — Microsoft · West San Antonio · under construction. 5 buildings under construction, 4 more planned (Baxtel, 2026)
- Microsoft Castroville — Microsoft · Castroville (Medina Co.) · planned. $482M facility announced July 2024 (DCD, 2024)
- Stream SA III — Stream Data Centers · West San Antonio · under construction. 200 MW hyperscale campus, third in region; broke ground 2024 (Stream/BusinessWire, 2024)
- Rowan Cinco — Rowan Digital Infrastructure · South Bexar County · under construction. 60 MW, targeted Q2 2026 launch (Baxtel, 2026)
- Vantage TX12 — Vantage Data Centers · San Antonio · under construction. 48 MW / ~432,800 sq ft, est. Q3 2027 (Baxtel, 2026)
- CyrusOne 6th SA campus — CyrusOne · San Antonio · planned. Sixth San Antonio campus announced (DCD)
- CloudBurst New Braunfels — CloudBurst / Evolve · Between New Braunfels & San Marcos · under construction. 1.2 GW AI campus; Energy Transfer natural gas supply agreement (w.media / Energy Transfer, 2025)
- Skybox Old Settlers — Skybox Datacenters · Round Rock · planned. Approved Feb 2026 without municipal tax incentives (Community Impact, 2026)
- Sabey Round Rock expansion — Sabey Data Centers · Round Rock · under construction. Campus expansion announced Aug 2025 (Community Impact, 2025)
- Project Comal (KDC) — KDC Real Estate · Taylor · planned. Six data centers permitted adjacent to Samsung's Taylor fab (Austin Free Press, 2026)
- Iron Mountain Taylor — Iron Mountain · Taylor · planned. Seven proposed buildings on ~500 acres SW of Samsung (Austin Free Press, 2026)
- Blueprint Georgetown — Blueprint Data Centers · Georgetown · under construction. $160M committed (Austin Free Press, 2026)
Power
Service territory: CPS Energy (San Antonio) · Oncor (Williamson County) · Austin Energy · New Braunfels Utilities.
- ERCOT large flexible load consumption hit ~54B kWh in 2025, up ~60% year over year; Texas SB6 (2025) adds interconnection and curtailment rules for 75+ MW loads (DCD, 2024; ERCOT)
- On-site/behind-meter gas is a corridor trend: CloudBurst-Energy Transfer 1.2 GW supply deal; Calpine-CyrusOne 'powered land' at Thad Hill Energy Center; Mesones Jarrell plans on-site generation
- CPS Energy has 15 ERCOT-approved transmission lines and ~$120M in recent contracts tied to data center load (DCD, 2024)
The regulatory picture
Enforcement. Texas is under federal OSHA jurisdiction (no state plan).
Licensing. Statewide electrician licensing through TDLR under the Texas Electrical Safety and Licensing Act (apprentice, journeyman, master); no separate municipal licenses.
Also in play. Texas SB6 (2025) imposes new ERCOT rules on 75+ MW loads; Round Rock approved Skybox's Old Settlers campus in Feb 2026 amid resident pushback and without tax incentives (Community Impact, 2026).
What it means for the work
SB6 curtailment obligations mean big sites will practice load-shed and transfer switching as routine operations. Every one of those evolutions is a planned switching event under 70E — and the discipline of treating routine operations as risk assessments is exactly what separates good programs here.
Texas SB6 curtailment rules mean 75+ MW sites will perform more live load-shed and switching operations - procedure-heavy NFPA 70E territory.
Behind-the-meter gas generation (CloudBurst 1.2 GW, Calpine powered land, Jarrell) puts facility crews around generation-class medium-voltage gear and gen-tie interconnections.
Williamson County's 1.6-1.9 GW buildout next to the Samsung Taylor fab is straining the regional electrical construction workforce - large new-hire safety training demand.
Federal OSHA jurisdiction with statewide TDLR licensing makes one uniform training offer viable across both metros.
Market context is half the picture. The other half is the decision walk — the nine questions the 2027 edition asks before anyone opens a door on energized gear. Run it against the task, then check the room pages in the Data Center Application Series.
NFPA 70E classes taught on the 2027 edition, against data center topology, about 55 times a year — live virtual weekly, and private onsite days in San Antonio / Austin run against your one-lines for crews of 15 or more.