Microsoft Castroville SAT83: Hyperscale Cloud & AI Infrastructure Hub in Texas

Status: Active Development / Phased Buildout | Location: 18844 FM1957 #2580, Castroville, TX 78009, USA

Project Overview

Microsoft Castroville SAT83 is a flagship hyperscale data center expansion representing an investment of more than $480 million, located within Microsoft's master-planned cloud campus in Castroville, Medina County, Texas. Developed to strengthen Microsoft's rapidly expanding Azure cloud platform and artificial intelligence (AI) infrastructure, SAT83 has been purpose-built to support next-generation cloud computing, high-performance computing (HPC), machine learning, enterprise applications, and large-scale GPU-based AI training and inference workloads. The facility spans more than 244,000 square feet and houses five dedicated high-density data halls designed to deliver scalable compute capacity while accommodating the increasing power and cooling requirements of modern AI infrastructure. Its modular architecture enables flexible deployment and future expansion, allowing Microsoft to rapidly scale services in response to growing customer demand across North America. In line with Microsoft's sustainability strategy, SAT83 incorporates advanced zero-water evaporative cooling technology that significantly reduces freshwater consumption during normal operating conditions, making it well suited to the climate of South Central Texas. The facility also integrates Direct-to-Chip Liquid Cooling (DLC) capabilities, enabling efficient thermal management for high-density GPU clusters and AI servers operating at elevated rack power densities. Power is supplied through dedicated high-voltage substations engineered to provide reliable, redundant electrical infrastructure capable of supporting mission-critical cloud operations. SAT83 is further connected to Microsoft's extensive San Antonio enterprise dark fiber network, providing high-bandwidth, low-latency connectivity between regional Azure facilities, cloud availability zones, and major telecommunications carriers. Combined with resilient electrical and mechanical systems, enterprise-grade physical security, continuous environmental monitoring, and 24/7 operational management, Microsoft Castroville SAT83 delivers a secure, energy-efficient, and future-ready hyperscale platform that supports Microsoft's long-term cloud expansion strategy while enabling reliable, scalable, and sustainable digital services for customers worldwide.

Quick Facts

Field	Value
Project Name	Microsoft Castroville SAT83: Hyperscale Cloud & AI Infrastructure Hub in Texas
Location	18844 FM1957 #2580, Castroville, TX 78009, USA
Status	Active Development / Phased Buildout
Commissioning	Phase 1 Go-Live: Target 2026–2028 / Active Multi-Building Campus Construction
Total IT Load	~50 MW to 70 MW Critical IT Power Capacity Allocation (SAT83 Building Allocation)
Total Capacity	~244,676 sq ft (~22,730 m²) gross facility footprint across 5 colocation halls (Campus total: 1M+ sq ft across 150+ acres)
Tier Level	Tier III Equivalent Hyper-Resilient Design / LEED Gold Certified Target / ISO 27001, ISO 14001, SOC 2 Type II Compliant
Project Type	Purpose-Built Owner-Occupied Hyperscale AI Cloud, Deep Learning & Enterprise Infrastructure Facility

City Profile

Header	Details
City Name	Castroville
Population	~3,500
Urban Agglomeration	San Antonio Metropolitan Area (~2.7 million population)
City GDP	estimated USD 180+ billion
Per Capita Income	~USD 55,000 (estimated)
City Tier	Tier 3 – Emerging Industrial & Digital Infrastructure Location
Key Strengths	Strategic location along Interstate 35 and near San Antonio; access to Texas' reliable power and fiber infrastructure; proximity to major enterprise and technology markets; business-friendly environment; available land for industrial and hyperscale developments; growing logistics and manufacturing base; increasing interest in data center and renewable energy projects.

Companies Involved

Header	Details
Developer / Operator	Microsoft
Strategic Infrastructure Partner	CPS Energy / Medina Electric Cooperative Utility Network & City of Castroville / Medina County Municipal Authorities
Construction Contractor	Specialized US Mission-Critical General EPC Contractors
MEP Engineering	Microsoft In-House Global Technical Infrastructure & Engineering Teams
Network Connectivity	Private enterprise optical backbone; subterranean path-diverse fiber entrance vaults; redundant Meet-Me-Rooms (MMRs); direct low-latency backhaul connecting Medina County to Microsoft's San Antonio fiber ring and major US network interchanges.
Power Infrastructure	High-voltage utility grid substations on-site, static distributed 2N / Block Redundant uninterruptible power supply (UPS) modules, automated switchgear, and multi-megawatt emergency backup generators running on renewable biofuel with multi-day on-site fuel autonomy.

Technical Specifications

Header	Details
Power Capacity	~50 MW to 70 MW Secured Utility Power Allocation (SAT83 Building Allocation)
UPS Redundancy	Block Redundant / 2N Static UPS Architecture
Cooling System	Closed-loop zero-water evaporation cooling system, Direct-to-Chip Liquid Cooling (DLC) readiness for high-density AI clusters, and automated BMS environmental controls.
Connectivity	Proprietary low-latency global fiber network connecting directly to regional Microsoft Azure cloud availability zones and major peering points.
PUE Target	< 1.18 Annualized Operational Design PUE
Energy Mix	100% Carbon-Free Renewable Energy backed by local Texas solar and wind Power Purchase Agreements (PPAs) under Microsoft's sustainability commitments.

Milestones

Header	Details
Announcement	2024
Construction Start	2024–2026
Phase 1 Go-Live	Target 2026–2028
Full Buildout	Active Building Development

Investment Details

Header	Details
Total Investment	Estimated $480,000,000 USD to $500,000,000 USD Building Capital Expenditure
Funding	Corporate Capital Expenditure (Microsoft Corporation)