OpenAI Group PBC today announced that it has signed a 20-year lease for a sprawling data center cluster in Ohio.

The campus is being built on the premises of a former uranium processing plant. The construction project is led by SB Energy, a SoftBank Group Corp. unit that develops data centers and energy infrastructure. SB Energy will own and operate the Ohio campus once construction is complete. 

According to OpenAI, the site will be supported by at least 10 gigawatts of new energy infrastructure. SB Energy plans to build a $33 billion power plant and link it to the data center campus using $4.2 billion worth of power transmission lines.

OpenAI didn’t disclose how much the campus itself will cost. According to the Wall Street Journal, the site is set to host hundreds of billions of dollars’ worth of Nvidia Corp. chips.

The graphics card giant is backstopping the first 4.25 gigawatts of data center capacity. The Journal’s sources stated that Nvidia could extend the credit support to the entire campus. Furthermore, the company has reportedly agreed to cover SB Energy’s losses if OpenAI scraps the lease and no other tenant is found. Nvidia will reportedly “pay any difference in the value, up to $105 billion” if the SoftBank unit has to sell the site.

“We are securing long-lived infrastructure for Nvidia compute so OpenAI can deploy the most productive AI factories that can be upgraded repeatedly with each new generation delivering more intelligence and better economics,” said Nvidia Chief Executive Officer Jensen Huang.

Traditional data center cooling systems evaporate a portion of the water they use to absorb server heat. As a result, they have to be continuity refilled. OpenAI says that its campus will use less water thanks to “closed-loop, air-cooled cooling systems” that don’t require refills. The company didn’t detail how the systems will work.

The coolant in closed-loop cooling equipment is usually a mix of water and a food additive called propylene glycol. The latter material prevents the coolant from freezing when it’s not supposed to and thus reduces corrosion. The water, in turn, usually goes through a filtering process that removes any minerals it may contain. That makes it less conductive, which lowers the risk to data center electronics.

Pumps circulate the coolant through server racks to absorb the heat generated by the graphics cards inside. From there, the warm water is routed outside the data center, where fans cool by running air over the pipes through which it flows. The coolant subsequently returns to the server racks and the process repeats. 

OpenAI expects construction to run through 2032. According to the company, the project will create 35,000 construction jobs and 2,500 long-term data center maintenance roles. The first 800 megawatts of computing capacity is scheduled to come online in 2028.

Nvidia is buying a $1.5 billion stake in SB Energy to support the project. The chipmaker could realize a return on its investment well before construction is complete: The SoftBank unit reportedly plans to go public as early as next month. SB Energy is reportedly seeking a valuation of up to $50 billion.

Photo: OpenAI