Fairwater

Microsoft unveiled a datacenter called Fairwater in September 2025¹ which built on a talk that Scott Guthrie gave at Build 2025.² The site is 315 acres with a total of 1.2 million square feet of floor space, and it was built with “46.6 miles of deep foundation piles, 26.5 million pounds of structural steel, 120 miles of medium-voltage underground cable and 72.6 miles of mechanical piping.”¹ It will begin production in 2026.³

The facility has three major components:

The GPU system is housed in the large, two-story building in the center of the above photo¹ and contains “hundreds of thousands of interconnected NVIDIA GB200 GPUs.”²

Storage and non-GPU compute systems are housed in the the long, single-story building to the side of the GPU datacenter. This building contains “exabytes of storage and literally millions of CPU compute cores”² which are used for data processing around AI training:¹

The water cooling facility is the third major building and is comprised of a large building and two “fins” which support the closed-loop dry coolers.¹ “Over 90%” of the facility uses dry cooling, while the remaining 10% use outside air and evaporative cooling.

Power and cooling

Photos of Fairwater suggest it is the $3.3 billion, 450 MW AI datacenter that Microsoft was building in Mount Pleasant, WI.⁴.

This facility is tied to a PPA that Microsoft signed with National Grid Renewables for 250 MW of solar generation.³⁵

History

Here’s a photo of the facility while it was still under construction in early 2025:²

Footnotes

1. Inside the world’s most powerful AI datacenter ↩ ↩² ↩³ ↩⁴ ↩⁵

2. Scott Guthrie’s keynote at Microsoft Build 2025 - Unpacking the tech ↩ ↩² ↩³ ↩⁴

3. https://www.cnbc.com/2025/09/18/microsoft-wisconsin-data-center.html ↩ ↩²

4. Microsoft data center will be the state’s largest electricity user. Power needs equal 300,000 homes ↩

5. https://www.datacenterdynamics.com/en/news/microsoft-signs-solar-ppa-with-national-grid-renewables-in-wisconsin/ ↩