All of the pieces are in place for data centers to operate in a more community-friendly way, a Johnson Controls executive says. It’s a matter of building operators putting the pieces in place and reaching out to communities to show them that the legacy facilities of five years ago are not the facilities that will be put into service in the years ahead.
“The equipment is here,” Mihir Nandkeolyar, Johnson Controls executive director of solutions architecture, said in an interview. “It’s been at the flat part of the hockey stick, but right now it’s at the curve and about to go very vertical.”
Newer compressor technology using lower-pressure refrigerants, for example, can work hard enough that no water is needed to keep a facility cool even in extreme heat, he said.
“These compressors … still run and still condense refrigerant when it's 140 degrees Fahrenheit," said Nandkeolyar. “It’s not a 140 degree day, but locally, where the equipment is [on the rooftop], it’s 135 degrees or 140 degrees.”
Magnetic bearing technology is part of the innovation because it doesn’t require lubrication, which loses viscosity as temperatures rise, affecting the operation of the compressors.
“To put a number to it, a data center running on a cooling tower, at the scale of some of these AI factories that are being built, would consume 12 million gallons on a hot July day, so taking that down to zero obviously leaves water available for the community to use in normal municipal ways,” he said. “We’ve seen a lot of the hyperscalers and many of the others move toward waterless designs, because it eliminates permitting risks or the perception they’re taking water from the municipal area.”
It will take time for building operators to get comfortable with the technology, he said.
“We’ve upgraded many of our labs to run up to 140 degrees and simulate this in front of our customers,” he said. “That gives them the confidence that they don’t have to include water in their system. Typically water is an insurance policy: we’ll run dry, we’ll run dry, and then, on that heat-wave day or those hot couple of days in July, we’ll start spraying [a water-based solution] to cool things down.”
Eventually, spraying won’t be necessary, he said. “They’ll get the confidence not to have to do that by really standing in a room or watching a screen that shows their equipment runs through a 140 degree local environment,” he said.
Innovation around fan technology is making operations quieter as well, which helps address one of the other major complaints communities have with data centers.
By combining what Nandkeolyar calls "overbuilt solutions” that sit on top of or adjacent to fans to dampen the noise with new technology that reduces how hard the compressors have to work, the two main sources of noise are reduced.
“Even though the fans are over there blowing a lot of air, 50 feet away you can hardly hear what’s going on,” he said. “It’s being attenuated, and then [with] the compressor technologies … the fans don’t have to blow as much air, so that doubly makes the sound reduced.”
Innovation in equipment density also means facilities don’t have to be as large as they’ve typically been, which means the building footprint doesn’t have to extend to the property line, so it can be further away from populated areas.
“You’re not occupying all the way out to the perimeter with this noisy equipment, even if we were to mitigate all the noise,” he said. “So, the more we can make the equipment compact, the less it comes toward the property line, the less the community or neighbors have to hear it if that’s a concern.”
To address the pressure data centers put on the grid and the cost and availability of power, more facilities are adding on-site power generation, which gives them the option of adding an absorption chiller to capture and repurpose the waste heat the generators produce.
“Instead of pointing the flues to the sky, point them into a heat exchanger and capture the heat off of them,” he said. “Now you’re delivering value to the operator because there’s no additional capital expense; you’re just exchanging a compressor-based [system] with an absorption-based [system] and you’re dropping their operating expense, because instead of electricity, it’s using the heat” that’s already there.
Johnson Controls has worked with data center operators to create a reference design that includes heat reuse to reduce energy use.
“You start moving toward a scenario where these data centers are not only islanded but start to become super efficient, super decarbonized, and even at the point where they can … put that waste heat to a good use,” he said. “So, it’s quiet. It doesn’t use water and also could provide [the local community] with heat on a winter day or as needed for desalinization or other processes.”
Correction: The piece has been updated to clarify that Johnson Controls has updated many of its labs to run up to140 degrees.
