- October 31, 2017
For decades, air-based cooling has been the go-to method for avoiding computer chip meltdowns. Now a group of liquid cooling technologies are vying to become the industry standard for data center operators, despite what at first sounds like a potentially disastrous combination of fluid and electronics.
These products range from the water-based systems of companies like Denmark-based Asetek and CoolIT Systems of Calgary, Canada—both more than a decade old—to the immersion of computer servers in a mineral oil-based blend by Green Revolution Cooling, an Austin, TX, company founded in 2008.
Add Madison, WI-based Ebullient to the mix. The company formed a year ago to commercialize a computer cooling technology developed by University of Wisconsin-Madison mechanical engineering professor Tim Shedd.
Ebullient’s system uses an air-conditioning liquid refrigerant that gets pumped through a tube and collides with a copper plate that is mounted to the computer chip. The refrigerant absorbs the heat given off by the chip and begins to evaporate. (The term “ebullient” means boiling.) The captured heat is carried through a tube to the roof of the building and released into the surrounding air, while a heat-exchanging device cools down the refrigerant so it can go through the process again.
Like other liquid cooling systems, Ebullient says its technology will allow data center customers to install more servers in their racks while also saving energy and lowering their electric bill. (Cost is a key consideration for data center owners, since cooling sometimes makes up half of a data center’s annual operating expenses, Shedd says.)
What’s interesting about Ebullient is the phase-change tactic and the use of a refrigerant that the company says won’t damage electronics if it leaks.
Ebullient is still in the early stages and has a lot to prove, including whether or not it can perform better than similar technologies from competitors. 3M, for one, is developing a liquid immersion technique that would also use an evaporative process but wouldn’t require pumps and tubes. Shedd says he’s aware of 3M’s technology, but that Ebullient uses a less expensive fluid and a system that is easier to implement and maintain.
Ebullient’s technology has been awarded two patents, with two more pending, Shedd says. The next steps for Shedd and business partner Jack Heinemann are securing seed funding and scoring the first few customers.
Shedd spoke with Xconomy about Ebullient’s technology and its plans to compete in a crowded field. The following is an edited transcript.
Xconomy: What are some of the advantages of Ebullient’s system compared with what’s currently on the market?
Tim Shedd: Right now, a typical data center needs almost as much electricity for the cooling system as for the computers themselves. Our value proposition is we can come in and almost eliminate the power that you need for cooling. We take it down by as much as 90 percent. So now you could almost cut the number of generators in half and still have enough power for your data center. We feel that that’s potentially a big win.
We use a low-pressure dielectric fluid that will never damage the electronics it cools, no matter how catastrophic a leak might be, in contrast with water, which can take a server down with just a few drops.
X: The coolant in your system changes phase, switching between liquid and vapor. Why is that important?
TS: That gives us a big advantage because it can take a lot more heat away when we let the liquid boil than if the liquid is flowing through…without changing phase. Just like when you’re sweating, our bodies can efficiently remove heat with a little bit of water by using evaporation. It’s the exact same concept. We’re trying to use a smaller amount of fluid to remove a lot of heat by using evaporation.
The boiling behavior also improves the cooling efficiency, allowing us to cool even the most intense heat sources with outside air exceeding 120 degrees Fahrenheit. Phase change also allows us to cool 2,000 watts (or more) per server.
X: Are you seeing traction in the market?
TS: We are still very early stage, with our first prototype approaching one year of operation and our data center prototype approaching six months. We are in discussions with a number of primarily enterprise-level data center operators, as well as the development arms of a couple of larger corporations. We don’t have the liberty to discuss specific names at this time, however. We are intentionally focused on the Midwest for the initial installations, but we are having discussions with organizations across the nation in anticipation of a rapid expansion once others realize the benefits Ebullient can provide.
X: Are you concerned it will be difficult to compete with larger liquid-cooling companies who have a head start in the market?
TS: The market I think is very large. The product space is very young. There are very few actual installs. The rate of installs is going fast. I look at it as a positive, to be honest. The more liquid cooling people at the moment, the better. They’re kind of preparing people for our technology.
X: What is Ebullient’s biggest challenge right now?
TS: Our biggest challenge right now I think is just perception. This is a very conservative industry. They’ve been doing air cooling for decades, and the tendency is to just stay with what you know. When people think liquid, they think water. They have to get over the fear of, “well this liquid will damage my computers.” Well, no, it won’t.
We just need to build trust. We’re looking to get those early adopters who are in a position where they just really need to look at a new technology because they’re at a limit of power distribution or air conditioning or both. We can provide some good solutions at a good competitive cost.