Amazon, Anthropic deals drive U.S. data center expansion

Aterio’s October 2026 update says September brought a surge in large U.S. data center projects, from Amazon’s 3.7 GW Homer City plan to Anthropic’s $13.7 billion GPU deal with RUM Group. The report points to a market increasingly shaped by massive power needs, customer commitments and construction visible on the ground.

Why it matters: - U.S. data center development is moving toward gigawatt-scale campuses, which raises the stakes for power access, permitting and infrastructure buildout. - Large customer commitments, like Anthropic’s agreement with RUM Group, are helping determine which projects get financed and built. - Satellite-confirmed construction is becoming a key filter for separating announced capacity from projects that are actually advancing.

What happened: - Aterio released its October 2026 U.S. Datacenter Monthly update covering major September 2026 activity across the United States. - The report highlights campus approvals, construction starts, customer commitments, behind-the-meter generation and project revisions. - Google’s Project Helium was approved by Barber County commissioners in Kansas. - Amazon’s Homer City campus in Pennsylvania is planned for 39 buildings across six sites and about 3.7 GW of allocated data center power. - Aligned Data Centers broke ground on its $10 billion, 2 GW Project Phoenix in Shippingport, Pennsylvania. - RUM Group signed a $13.7 billion, six-year GPU services agreement with Anthropic for its Maysville, Georgia data center. - Fluidstack began site clearing at its Harlingen campus near Rio Hondo, Texas. - Google advanced vertical construction at its Southland campus in Council Bluffs, Iowa.

The details: - Aterio says the September pipeline also included major activity in Ohio, Iowa, Kansas, Utah, Colorado and Georgia. - Amazon’s Homer City project is supported by a 4.5 GW power plant, with phased completion planned from 2030 through 2036. - Google’s Project Helium is expected to begin construction in early 2027, with Building 1 targeted to start operations in 2030. - Aligned Data Centers’ Project Phoenix is planned for three buildings across about 650 acres. - RUM Group’s Maysville campus is planned for two buildings with 120 MW of current capacity and potential expansion to 180 MW. - The Anthropic agreement includes a 10-year warrant that lets Anthropic buy up to 50.81 million RUM shares. - Creekstone Energy revised its Delta Gigasite in Utah to a planned 26-building campus. - Creekstone’s Phase 1 includes 220 MW, while full-campus capacity could exceed 10 GW across solar, natural gas and storage. - Karis Critical is proposing the Peosta Energy and Data Campus in Iowa with about five buildings totaling 3 million square feet and 500 MW to 850 MW of onsite natural gas generation. - The Karis Critical project remains at the concept stage because of city and county moratoria. - Meta is planning six data center buildings at its Prometheus campus in New Albany, Ohio, totaling about 1.66 million square feet. - Meta’s Prometheus campus is tied to an approximately 500 MW behind-the-meter facility across about 131 acres and a stated project cost of about $3.05 billion. - Vantage Data Centers reduced its Trident Data Center at Windler in Aurora, Colorado to two two-story buildings totaling about 859,656 gross square feet across 108 acres. - Vantage removed a third building from the earlier proposal. - Aterio’s satellite imagery shows structural steel framing rising on Google’s newly tracked Buildings 7A and 8A in Council Bluffs. - Roof work and generator-yard paving are underway on Google Building 7A. - Each of those Google buildings is estimated at about 93.5 MW and 288,000 square feet based on air-permit generator specifications. - Fluidstack’s Harlingen campus is planned for five buildings and up to 1.5 GW, with Phase 1 shown as two buildings. - The Harlingen site covers about 1,065 acres and sits near Rio Hondo, Texas. - A worksite permit from Cameron County preceded the clearing activity at the Fluidstack site.

Between the lines: - The report shows a shift from simple announcements to projects paired with power plants, onsite generation or dedicated utility commitments. - Behind-the-meter power is becoming a major strategy for campuses that need large capacity without waiting on traditional grid expansion. - Aterio’s framing suggests that approval alone is no longer enough; visible construction and secured power access are now the best signs of forward momentum.

What's next: - Project Helium is scheduled to move into construction in early 2027. - Amazon’s Homer City campus is expected to phase in through 2036. - Google’s Southland and Fluidstack’s Harlingen campuses should offer more visible construction milestones if current work continues. - Permit approvals, air modeling and utility coordination will likely determine how quickly the larger Utah, Iowa and Colorado projects can move forward.

The bottom line: - September’s biggest data center stories were not just about scale, but about whether campuses could secure the power, customers and site progress needed to turn plans into buildings.