IN² at 10 Years: Cohort 1 Participant Uses Liquid To Cool Computers
In 2024, the Wells Fargo Innovation Incubator (IN2) celebrates its 10th anniversary under the management of the National Renewable Energy Laboratory’s (NREL’s) Innovation and Entrepreneurship Center. As part of the 10-year celebration, NREL is looking back at IN2’s inaugural cohort to see how the companies have progressed over the last decade.
![A man in safety goggles and a red shirt slots a device into a server rack.](/news/program/2024/images/20240715-in2-at-10-years-cohort-1-participant-uses-liquid-to-cool-computers-35354.jpg)
NREL scientist Eric Kozubal works with the original LiquidCool Solutions technology during its time in the IN2 program 10 years ago. Photo by Dennis Schroeder, NREL
Early in its history, LiquidCool Solutions went by the name Hardcore Computer. The first systems the startup built were high-performance gaming systems, thus the original name.
“If you could cool the Ferraris of computing and do it with a liquid, we’d get a little bit of the wow factor,” said David Roe, LiquidCool program manager.
However, the startup had to change its name for a very important reason. “We couldn’t get through spam filters at many of the large companies,” said Herb Zien, former chief executive officer and now vice chairman of LiquidCool.
LiquidCool uses an electrically nonconductive heat-transfer fluid to cool down electronics, often in data centers. Traditionally those centers were cooled with air, but as chips get stronger to manage artificial intelligence and machine learning, they also get much hotter.
“It’s been known for decades that you can cool certain electronics using a fluid,” Roe said. “Electrical transformers are cooled using a very similar fluid. One of the challenges we’ve had is that, for a lot of reasons, data center operators were reluctant to bring liquid in. But now they have to—the chips are just too hot. The fluid removes heat but does not short out the electronics, and in our case, we can remove the heat from the hottest chips and remove the heat from all the other components in the liquid as well.”
Instead of using a traditional water-based approach, LiquidCool uses a commercially available dielectric liquid that conducts heat but not electricity. It removes heat and does not cause any short circuits.
“There’s also a cold plate that’s submerged in the liquid,” Zien said. “We can remove heat from the hottest chips and remove heat from all the other components in the same liquid. It’s a very efficient way to get the job done. We’ve reduced the amount of power to cool a data center by up to 98% compared to air cooling.”
When NREL Senior Mechanical Engineer Eric Kozubal first learned about the company’s technology, he was eager to get to work on it through the first IN2 cohort.
“It immediately struck me that there was good potential here to recapture energy better than any other technology,” Kozubal said. “Typical data centers use up to two times more energy to cool their systems than to compute. Furthermore, the use of cooling towers to reduce the coolant temperature results in significant water consumption through evaporation. With LiquidCool’s technology, one can cool a data center using no water because a cooling tower is no longer needed. Rather, a simpler, air-cooled radiator can be used to transfer heat from the coolant to the ambient air. Better yet, the coolant temperature can rise to 140 °F (60 °C), and the heat can easily be reused to warm our buildings in the winter.”
Zien and Roe believe the shift from water- and air-cooled data centers to liquid cooling is inevitable.
“Chips are getting so hot that there’s going to be no alternative,” Zien said. “Any building that is going to house equipment to support artificial intelligence and machine learning is going to need a liquid infrastructure. The last air-cooled data center might have already been built.”
Ten years ago, participating in IN2 felt more like an experiment than a proven model, but Zien and Roe believe it was a crucial step forward for LiquidCool.
![A server rack sits in a server room with more servers in the background.](/news/program/2024/images/20240715-in2-at-10-years-cohort-1-participant-uses-liquid-to-cool-computers-37354.jpg)
The LiquidCool Solutions rack was installed in NREL’s Energy Systems Integration Facility during testing nearly 10 years ago. Photo by Dennis Schroeder, NREL
“I can’t tell you how important it was for a small company like ours to get this boost from NREL and Wells Fargo,” Zien said. “That’s a big deal for a small company. We were blown away by how great it turned out to be, and we had no expectations.”
As part of the work with NREL, Kozubal wrote a report about LiquidCool’s technology that the company still uses today. NREL tests showed LiquidCool can reclaim 90%–95% of the heat for reuse, capturing it to either help heat a building or heat water in the building. This makes the whole system more sustainable.
“We use the results of that original study to promote our technology,” Roe said. “This type of third-party validation is very valuable, especially when it’s from NREL. We use it every day to show potential customers the low risk and high reward.”
Over the past decade, LiquidCool continued to improve its technology. It now has four installations and hopes for many more on the horizon.
“Our pipeline is growing pretty fast because air cooling is in the rearview mirror,” Zien said. “Eventually, I think all the equipment in the data center will be cooled by some kind of a liquid system.”
The fluid itself also never needs to be replaced. One installation just hit the seven-year mark, and it is still running with the original fluid. Replacing air-cooled data systems also dramatically cuts down on the noise. Instead of personnel having to wear ear plugs due to deafening fans, the liquid makes it completely silent.
According to Kozubal, LiquidCool can also cool down very high temperatures. Many other systems can handle temperatures up to 100°F. However, LiquidCool works up to 140°F, and it has the potential to manage temperatures hotter than 160°F.
“LiquidCool developed its technology that was a bit ahead of its time, but now people are realizing that their technology, which has been de-risked through demonstrations and field installations, can quickly be implemented,” Kozubal said. “I’m sure everybody else is racing to do what they’ve already done 10 years ago. But if people need a solution right now, LiquidCool can fill that gap. They are uniquely suited to come in with a solution right away and lower the power draw of these large data centers.”
Learn more about the IN2 program.
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