Digital Realty Commits $10 Billion to Quadruple Japan Data Center Capacity

Digital Realty will pour another $10 billion into Japanese data centers over the next decade, a buildout with joint venture partner Mitsubishi Corp. that would lift its capacity in the country from 193 megawatts to roughly 700 MW — nearly a quadrupling, CEO Andy Power told Nikkei Asia.

The commitment makes Japan the company's top investment destination in Asia. Digital Realty has already sunk $4 billion into the country, counting projects still in development. Its existing 193 MW sits mostly around Tokyo and Osaka, two metro markets where land and power for hyperscale facilities have grown scarce.

Nikkei published its report on Nov. 15 Tokyo time, drawing on an interview with Power conducted last month. Digital Realty has not issued its own release on the plan, and the report leaves open how the $10 billion splits between Digital Realty and Mitsubishi.

Why Japan, and why now?

Power didn't mince words about the geopolitical calculus behind the bet. He described Japan as a "safe haven" with "foundational strength" in the rule of law, regulation and business focus. Many other Asian countries, he said, "have not had the history and consistency when it comes to infrastructure, when it comes to business, when it comes to law, like Japan has."

That stability argument matters commercially. Data center operators weigh decades-long asset lives against political and regulatory risk, and Power is effectively saying Japan's premium is worth paying.

He also conceded that the AI spending wave may not run in a straight line. "We're certainly navigating what I would call a volatile capital markets backdrop," Power said. "In the long term, this is a tremendous opportunity up and to the right. But that doesn't mean there's not going to be peaks and valleys along the way."

What gets built: inference first

In Japan, Digital Realty plans to prioritize facilities for AI inference — the stage where trained models answer user queries, rather than the training runs that have driven the largest GPU clusters. Inference workloads favor distributed capacity close to end users, which fits a multi-site Tokyo-Osaka footprint.

The customer base backs that strategy. Digital Realty's Japanese roster is approaching 100 companies, and it spans:

• Amazon Web Services and Microsoft
• Financial institutions
• Autonomous driving developers
• A Japanese AI model developer, with a working relationship set to begin soon, according to Nikkei

Globally, the picture is larger still. Digital Realty runs about 3,000 MW of capacity worldwide and plans to add another 9,000 MW. Asia-Pacific, Japan included, accounts for 10% of revenue — against 53% for North America and 29% for Europe — which leaves substantial room for the region's share to grow if the Japanese bet pays off.

The Mitsubishi joint venture and KIX15

Digital Realty operates in Japan through MC Digital Realty, a 50/50 joint venture with Mitsubishi Corp. In October, the venture began constructing KIX15, a 24 MW data center on its campus in Ibaraki City, Osaka Prefecture. It is due to start operating in the fourth quarter of 2028.

Once KIX15 comes online, the Japan portfolio will reach 10 data centers with about 220 MW of IT capacity — a figure that itself will have grown from today's 193 MW before the $10 billion program fully kicks in.

Who else is racing in Japan

Digital Realty is far from alone. Australia's AirTrunk plans to raise its Japan investment to as much as $30 billion over five years, Nikkei reported — triple Digital Realty's commitment on a faster clock. NTT Data, meanwhile, is planning a large AI data center for Anthropic.

That competitive field sets up a scramble for power, land and skilled labor in Japanese metro markets, with the winners likely determined by who secures grid capacity soonest. Whether Japan's infrastructure can absorb this much demand — and whether inference growth justifies it — will shape pricing and utilization across the market well past 2030.