SpaceX wants a 6-gigawatt AI data center in the Arizona desert

SpaceX wants to build the Cochise Supercomputer Campus on 747 acres along U.S. Highway 191. The land sits near the Willcox Playa, a dry lake bed about 80 miles east of Tucson.

The application was filed with Cochise County by Tombstone Resources LLC, an affiliate of SpaceX's data center arm. It asks for a special use authorization, which is the county's permission to use land in a way the zoning does not normally allow.

At a community meeting on November 4, a SpaceX executive removed any doubt about who is behind it. Riley Trettel, who leads energy and supercomputer development at SpaceX, said the company is the owner and, with approval, will build and own the project long term.

The campus would have up to nine data center buildings. Each one measures 493,000 square feet, which is a bit larger than eight football fields side by side.

The plan has four stages of about 1.5 gigawatts each. A gigawatt is a billion watts, roughly what a large power plant makes. At full build-out the campus would need up to 6 gigawatts.

• Site: 747 acres on two plots, bought from power companies.
• Buildings: nine, at 493,000 square feet each.
• Power: up to 6 gigawatts in four stages.
• Investment: Trettel put the total at up to $50 billion.

By the numbers: only two U.S. proposals are bigger, according to local reporting: a 9-gigawatt project in Utah and an 11-gigawatt project near Amarillo, Texas.

Not as it stands. The proposed power seller, Sulphur Springs Valley Electric Cooperative, peaks at about 250 megawatts in summer. The first stage alone would need about six times that, and the full campus about 24 times.

That is why the grid is a big part of the plan. SpaceX says it will spend $3.6 billion on new transmission lines, which are the high-voltage wires that carry power over long distances. The lines would later be handed to Arizona Electric Power Cooperative at no cost to the cooperatives.

In real life Think of a small-town water pipe that suddenly has to feed a stadium. Someone has to lay a much bigger pipe first, and here SpaceX says it will pay for it.

Trettel put it plainly: "We are paying for everything, every single cent." The cooperative says the developer must fund every upgrade and is negotiating protections in case the project closes early or draws less power than requested.

The site is next to the Apache Generating Station, a 626-megawatt plant that burns coal and natural gas and also uses solar. It had been marked for retirement by 2028 before it received nearly $21 million in federal upgrade funding this summer.

The plans also include two backup systems:

• Battery storage: a 24-gigawatt-hour system, which stores power so the campus draws steadily even when demand jumps around.
• Gas generators: 90 megawatts of gas-fired backup generators.

When the computing can start depends on the grid upgrades being finished. SpaceX says construction could begin in March 2027 if the county approves zoning.

Water is usually the flashpoint in Arizona data center fights, so SpaceX led with it. The company says the campus would be dry-cooled. That means it uses air, not evaporating water, to carry heat away from the computers.

Trettel promised zero industrial water use for cooling, with the servers run hotter to avoid evaporation. No new well would be drilled in the Willcox groundwater basin.

The application estimates a one-time fill of 3 to 5 million gallons and 2 to 3 million gallons a year for sanitation. That is roughly what 20 to 30 Arizona homes use in a year. An existing well would supply drinking water, maintenance and equipment cleaning.

The catch: the numbers come from SpaceX's own application. The company has not yet said how much the whole project will cost in Arizona beyond the $50 billion ceiling Trettel gave.

Hundreds of people packed the meeting at Cochise Elementary School. Many carried protest signs, and booing interrupted the presentation more than once. An online petition against the project had nearly 2,100 signatures by Thursday.

Residents asked about groundwater, electricity costs, wildlife, noise and what county officials knew before the project became public. Some were in favor. One attendee said, "We need AI centers. It's the future." Another said, "We don't know enough, therefore just say no."

SpaceX points to the upside. Trettel cited about 1,000 permanent jobs, about 3,000 construction jobs, $30 million to $100 million a year in property tax revenue and a one-time sales tax benefit of up to $450 million.

The site is a few thousand feet from the Willcox Playa, a wintering ground for sandhill cranes, which are federally protected birds. Arizona Game and Fish and the U.S. Fish and Wildlife Service will review the designs.

SpaceX says it would use low-profile buildings, downward-directed lighting and wildlife-friendly fencing.

Cochise County also adopted a dedicated data center zoning code in April. It sets standards for noise, water, decommissioning (taking a site apart when it closes) and financial guarantees if a project shuts early.

SpaceX's data center arm, SpaceXAI, came from folding xAI into SpaceX. It runs a cluster around Memphis, with one site in Tennessee and the rest across the border in Mississippi.

That cluster runs Grok, the company's chatbot. It also sells computing capacity to customers that include Anthropic and Google.

Cochise would be the first campus outside Memphis and Texas. SpaceX announced a separate project in Texas on Monday that will cost about $24 billion. In Mississippi, environmental regulators found that SpaceXAI began construction on one data center without the permits it needed.

What's next: the Planning and Zoning Commission hearing is on December 9 at 2 p.m. in Bisbee. The county moved it up two hours to handle the expected crowd.

• If you live nearby: the December 9 hearing is where the zoning question gets decided, and the county takes public comment.
• If you pay an Arizona power bill: the co-op says the developer must fund the upgrades. Watch how the protections are written.
• If you use Grok, Claude or Google's AI: this kind of campus is where the computing behind them comes from, so these fights shape how fast it grows.
• If you follow AI: power, not chips alone, is now the limit. Counties are where gigawatt plans win or lose.