LAS VEGAS – A data center startup offers a new take on popular approaches to liquid cooling, and is hoping it can build a following beyond the high-performance computing community, which has traditionally been the primary market for liquid cooling solutions.
Ebullient Cooling is cooling processors using Novec 7000, a liquid coolant from 3M that has proven popular in immersion cooling solutions for the bitcoin market. Instead of dunking servers in a bath, Ebullient is delivering the dielectric fluid directly to the processor, using a piping system to bring the liquid inside the server chassis. Several existing liquid cooling vendors use internal loops to bring fluid to the chip, but use water as the coolant.
“There’s still a lot of discomfort with water in the data center industry,” said Tim Shedd, the Chief Executive Officer of Ebullient Cooling. “I was motivated to do this with a dielectric fluid that wouldn’t damage the equipment (in the event of a leak).”
Shedd isn’t bashful of demonstrating the leak-proof nature of the Novec fluid. Standing next to his demo rack on the expo floor at the recent Data Center World Global conference, Shedd opens a bottle containing Novec and pours it out onto his mobile phone. It evaporates in seconds.
Seeking Better Cooling Solutions for HPC
Ebullient is the latest in a series of startups developing data center cooling solutions using liquid cooling. In recent years we’ve seen companies offering new solutions using immersion and cold plate technology, as well as new approaches to direct-to-chip cooling. Most of these newcomers are targeting the market for high performance computing (HPC), where workloads are pushing the boundaries of power density.
But Shedd believes Ebullient may be able to grow beyond the HPC realm and gain traction in the market for small data rooms and micro data centers for small businesses, and is designing its offering to address the needs of that market.
Shedd is a professor in mechanical engineering at the Unversity of Wisconsin, specializing in cooling of electronics using boiling and condensation. His work included a research collaboration with cooling specialists at the Cray facility in Chippewa Falls, Wisconsin.
“My motivation was to take the high-end work they’re doing with direct cooling, and see how we could make it affordable to the average user,” said Shedd, who has been developing the concept since 2010.
Two-Phase Cooling
Ebullient was founded in 2013 to create commercial cooling products. In January the company raised $2.3 million in financing from a private investment group.
The Ebullient system uses two-phase cooling, in which heat from the chip is dissipated by interacting with a fluid, which is vaporized by the heat. 3M’s NOVEC is ideal for this, as it has a low boiling point. It has been used in industrial-scale immersion cooling for bitcoin specialists, whose high-density equipment generates high heat loads.
Ebullient’s approach features a “boiling jet” module that sits atop a copper plate that attaches to the processor. The system is fed by a tubing loop containing NOVEC, which vaporizes as it encounters the heat from the chip. Each fluid loop can cool up to 2kW of heat, allowing it to cool multiple processors within a server chassis. The system can be adapted to any type of CPU, and is also being used to cool GPUs.
Each loop connects to a manifold in the rear of the rack, which is fed by a fluid distribution unit (CDU). The loops can easily disconnect from the manifold, allowing an individual server chassis to be serviced while the remainder of the rack continues operating.
In its early implementations, Ebullient used a centralized CDU that could support up to 480 servers across multiple racks. The company also offer a variety of manifolds that provide connections for between 10 and 30 servers within a rack.
Early customers include the Poznan Supercomputing and Networking Center in Poland, the University of Wisconsin and Service Logic. “We’re very early and have just started rolling out products,” said Shedd. “We like high-density workloads because they show off the capabilities of the system. Universities are good clients as early adopters.”
At Data Center World, Ebullient launched a smaller in-rack form factor for its fluid distribution unit. TheER32 system takes up 6 rack units of space, allowing end users to create a self-contained rack that includes the coolant distribution system and up to 30 servers.
Shedd says the rack-level product makes the Ebullient offering more attractive for small to medium sized businesses who need IT gear on-site, but can’t afford to build their own data center. Liquid cooling offers potential economic benefits by allowing users to operate servers without a raised floor, computer room air conditioning (CRAC) units or chillers. It also eliminates the need for server fans, which can also be power hogs.
Less Racket in Your Rack
“Many businesses need on-site servers to support critical business functions, but a vast majority of those businesses lack purpose-built rooms to house their servers,” said Shedd. “Often, a rack of servers is placed out of the way, in a closet or utility room, that lacks adequate cooling, and the servers overheat. The ER32 delivers precision cooling to servers in these small spaces without the cost or hassle of installing a new air conditioning system.”
That places Ebullient among the vendors targeting opportunities to provide rack-level micro data center solutions, which has been a niche for specialists like Elliptical Mobile Solutions. This market, which may be boosted by the edge computing trend, is also a growing focus for Schneider Electric.
Ebullient says one differentiator is that it’s less noisy than traditional server racks.
“The Ebullient ER32 is incredibly quiet. You can barely hear it run,” said Greg Crumpton, Founder of AirTight FaciliTech, an Ebullient customer that was one of the beta testers of the rack-level system.
That matters in an office environment. Case in point: Ebullient is working with a partner on a liquid-cooled workstation powered by a combination of Intel CPUs and NVIDIA GPUs, providing extreme power in a desktop form factor without loud fan activity.