As data center power demand skyrockets, tech companies are looking for ways to reduce power usage wherever possible. Cooling can account for approximately 40% of a data center's energy consumption, according to McKinsey, so cooling is an obvious place to start.
Most data centers are cooled by blowing cold air over the servers. The problem is that air is a fairly inefficient way to move heat. This is why companies like Amazon, which is investing heavily in power-hungry AI servers, are turning to liquid cooling.
Nexalus, one of the Irish-based startups, claims that its hot water approach is not only more efficient, but also produces waste heat that can actually benefit other industries.
The core of Nexalus' liquid cooling system uses what's known as direct-chip liquid cooling, where a heat sink on top of the CPU or GPU is plumbed to facilitate coolant flow. Unlike other designs, it does not use small channels to direct liquid flow to the cooling plate. Instead, it pumps liquid through small holes toward the cooling plate, much like a fire hose directs water to a fire. These microjets direct the liquid to the hottest spots on the chip, allowing the system to operate at lower pressures. CTO Tony Robinson said the company can tailor MicroJet to a variety of chips.
Nexalus encloses the entire server inside a box that fits in a typical 1U rack space. Inside the sealed box, other components of the server are cooled using fans, and a heat exchanger on the exhaust side extracts heat from the air so it can be reused. This liquid is mostly water with a small amount of propylene glycol, the same compound used in car radiators. The heated liquid is pumped out of the case and cooled in a heat exchanger, allowing the heat to be released into the air or transferred to another loop connected to a building or industrial user.
Liquid cooling setups allow you to cram more servers into your data center, saving real estate and construction costs. It also has the potential to reduce water usage, which many data centers use for air conditioning.
The question of what to do with the excess heat remains. Most of it is now emitted into the atmosphere. But Nexalus offers companies the opportunity to turn their waste heat into a potential revenue source by selling it to industrial users, heating districts, or even using it to offset their own utility costs. I believe that it can be changed to
“We're not empowering people, but we're unlocking more power,” Ken O'Mahony, the company's co-founder and CEO, told TechCrunch. . “If the homes receiving hot water from us aren’t using their electrical systems to heat their water, the grid itself can provide more power.”
It may sound counterintuitive, but you can use boiling water for cooling, as long as it's colder than what you're trying to cool. The heat pumps that exploded in homes and commercial buildings work on exactly this principle. Most data centers generate heat, but usually not enough heat for anyone to take advantage of. O'Mahony says Nexalus believes that by using hot water, it can make a difference while reducing power consumption by 35%.
To provide heat to other customers, Nexalus is working with Munters, which makes data center HVAC systems. To recover heat from servers, the startup has worked with Dell and is now working with HPE to ensure its liquid cooling system is a drop-in replacement for air cooling, the startup told TechCrunch exclusively. Ta. Systems are sold directly or through Dell and HPE integration partners.
O'Mahony envisions small data centers in cities taking advantage of existing district heating schemes or, if servers occupy the first or second floor of a high-rise building, reusing heat within the building. I am. Additionally, large data center operators may partner with industrial companies, such as food manufacturers, that require heat to operate their businesses.
“It's hard to believe that with this much energy, it wouldn't make economic sense to build district heating systems to co-locate with food production or capture carbon,” Robinson said.