Josh Claman’s favorite early Accelsius memory involved a conference booth. In April 2024, at Data Center World, visitors came looking for the company. They had heard about its cooling technology and wanted to talk. The team had been invited onto four panels. After more than a year spent developing something it could take to market, attention had become conversation.
There are grander-looking milestones in a technology career. A crowded booth, however, has a particular appeal to someone trying to sell unfamiliar equipment. It means the argument has escaped the meeting room. Someone else has decided the problem is worth walking across a convention floor to discuss.
Claman had returned to data centers in 2022 as the founding CEO of Accelsius. He brought experience running established technology businesses to a company formed around cooling research. The assignment was practical: take an approach developed at Nokia Bell Labs and help build an enterprise product around it. Then the demand for AI computing made the heat coming off processors a rather urgent subject.
A career spent on the other side of the purchase order
Claman grew up in a small farm town in Illinois. His subsequent working life took him into global technology businesses, including NCR and Dell, with responsibilities across Europe and the Americas. It is a career that makes the commercial side of infrastructure visible: the organizations, channels and service arrangements that connect a technical product to its users.
At Dell, his roles included running the UK and Ireland operation, leading the Americas large-enterprise business, and overseeing public-sector and channel operations in Europe, the Middle East and Africa. He later became president of online marketing business ReachLocal. In April 2015, Stratasys appointed him chief business officer, bringing him into 3D printing and additive manufacturing.
His education includes a BA from the University of Illinois and an MBA from the University of South Carolina. The route into Accelsius was through operating businesses rather than a public claim to having invented a cooling process. That distinction gives the story its shape. A laboratory can establish that something works. An operator must help establish how it will work for a customer.
Bell Labs supplied the beginning
Innventure formed Accelsius in 2022 to commercialize thermal technology originating at Nokia Bell Labs. Claman joined to build the company around that starting point. Research rights are a useful inheritance; they do not arrive with an installed base, a distribution network or a service organization attached. Those still need people.
The cooling approach is called two-phase, direct-to-chip. A refrigerant circulates through cold plates attached to processors. As it absorbs heat, it changes from liquid into vapor. A condenser turns it back into liquid, and the loop continues. The change of state does useful thermal work. Boiling, usually an invitation to turn down the stove, has a job here.
NeuCool keeps its refrigerant in a contained circuit. The processors remain in servers, with cold plates doing the work at the chip. Calling the approach water-free refers to that refrigerant circuit; the wider building’s heat-rejection arrangement is a separate design question. Physics may be concise. A useful explanation of the plumbing needs another sentence.
Claman’s public advice to hardware entrepreneurs includes a warning about getting ahead of their resources. “Don’t get too far ahead of yourself,” he says. He advocates iterative operational changes. That is a revealing emphasis from an executive selling a change in infrastructure: the buyer must be able to absorb the change, and the supplier must survive delivering it.
An unusual recruiting brief
Accelsius’s early team gives this story some texture. When the company was recognized in Austin Business Journal’s 2024 Best Places to Work program, Claman pointed to backgrounds including submarine service, farming, ranching and motor racing. He spoke about cultural fit alongside professional experience. The résumé pile apparently contained more than the usual collection of familiar technology employers.
The award followed an employee survey covering workplace engagement and leadership. Accelsius had doubled its workforce during 2023 to reach 40 employees. For a young hardware company, growing the staff also means growing the number of handoffs: from research to engineering, from engineering to supply chain, from a sales promise to the people expected to fulfill it.
In his discussion with Activated Scale, Claman emphasizes curiosity, collaboration, kindness and transparent communication. These are his stated hiring and leadership priorities. They are modest words next to the language of advanced computing, but a product assembled by specialists requires them to share what they know.
“I want people to smile in the office.”
Josh Claman · on building company culture
It is an unusually everyday ambition to hear alongside a discussion of cooling dense computing equipment. It also makes the executive easier to picture. Behind the technical explanations is someone talking about what it should feel like to turn up for work.
The customer needs to see it work
A cooling system asks for confidence at close range. It sits beside equipment a customer depends on. Accelsius’s products include redundant, replaceable components, monitoring and controls. These details speak to the person who will eventually have to service the system while the surrounding operation carries on.
Claman has emphasized the value of showing customers the technology in a working setting. In July 2025, Accelsius announced plans to place its NeuCool IR80 system at Equinix’s Co-Innovation Facility in Ashburn, Virginia. The lab gives infrastructure companies a place to demonstrate equipment and customers a way to examine it. A drawing can introduce a cooling loop. An operating installation lets the questions become more specific.
The distribution work follows a similar logic. Accelsius’s Accelerate partner program brings together integrators, equipment manufacturers and infrastructure providers. It includes training, presales assistance, joint selling and access to the company’s Austin laboratory. Selling through partners means other organizations must be able to understand, size and support the equipment.
There is a direct connection to Claman’s earlier channel responsibilities. Making a technical product available involves people who may never have helped design it. They need enough knowledge to recommend it and enough support to deliver it. The work is less photogenic than a processor launch, though considerably more useful when somebody is waiting for an installation.
By July 2025, Accelsius reported a fivefold increase in data center deployments during the first half of the year, alongside partnerships extending into Europe and Canada. The announcement also described participation in the Department of Energy’s ARPA-E COOLERCHIPS effort. These were distinct routes toward commercial reach and technical validation, rather than a single event that settled the adoption question.
Money with a trade attached
Accelsius announced a $24 million Series A in November 2024. Its stated plans included international expansion and hiring across engineering, manufacturing, sales and operations. The list itself is instructive. Cooling research was becoming a business with several departments that needed to grow together.
In January 2026, the company announced a $65 million Series B led by Johnson Controls, with Legrand participating. The investors brought experience in the infrastructure around data centers: thermal management on one side, electrical systems, racks and connectivity on the other. Their involvement put the cooling company in contact with businesses serving the broader facility.
Separate announced rounds. Financing amounts are not revenue or a company valuation.
That fits the practical problem Claman has been discussing. A customer buying chip cooling also has to consider the rest of the building. Equipment must connect to other equipment, and the organizations selling it must coordinate. A strategic investor can bring relevant experience and relationships, alongside the money needed to manufacture and expand.
Claman’s comments in an October 2024 industry discussion also favored flexibility in facility design. He argued that existing data centers deserved consideration for retrofits and that facility infrastructure should leave room for multiple cooling approaches. The position is useful context for an executive advocating a particular technology. Customers make investments whose useful lives extend beyond a single sales conversation.
The next job is still a building job
By April 2026, Accelsius was broadening how customers could evaluate and deploy the technology. The IR150 combined a cooling distribution unit, 42U of IT space and liquid and vapor manifolds in one enclosure, with up to 150kW of capacity. The HyperStart program offered engineering and validation support for operators planning larger deployments.
Claman was also making a case for more universal liquid-cooled servers. In March, he argued that compatible server components could give customers greater freedom to choose between water-based and refrigerant-based systems. It was a proposal about the friction surrounding adoption: reducing the equipment changes needed when a customer wants a different cooling architecture.
Then came a change in his own job. Accelsius announced on May 27 that John Hewitt would become CEO and Claman executive chairman. The transition was effective July 6. Hewitt had served on the board since the company’s founding; Claman’s continuing responsibilities centered on strategic partnerships, customer relationships and capital strategy.
In September, he appeared as executive chairman in a JSA interview at Datacloud USA, discussing two-phase cooling and data center efficiency. The public-facing work continued after the handover, with Claman still explaining the approach to an industry audience.
Those responsibilities keep him close to the commercial questions that framed his arrival. How does research become a product? How does a customer become comfortable enough to buy it? How does the organization around the equipment grow without outrunning its ability to deliver?
The booth in 2024 offered one small answer: people came over and asked. The subsequent work has involved giving them increasingly concrete things to examine, from demonstrations to product configurations to partner arrangements. Claman’s Accelsius chapter is a story about making cooling equipment, with all the ordinary business obligations that surround an unusual piece of engineering. The heat gets the attention. Someone still has to organize the installation.