Data-center consumption of energy and water for server-cooling has reached astonishing volumes, but a pair of innovative companies is applying the brakes to this runaway train.
The ambitious partnership and its technologies were presented during a July 25 “analysts day” at the Danbury, CT headquarters of Inertech, which designs, engineers and manufactures modular data pods and energy-efficient cooling systems for a wide range of industries.
Its paradigm-shifting technology to slash data-center consumption of water and electricity is available through Skanska, a global construction company whose Mission Critical Excellence Center has been tasked with designing data centers with far greater efficiencies than industry norms.
Moderating a Voracious Energy Appetite
U.S. data centers annually consume 575 gigawatts, or 2% of all the power delivered by the grid – with half that energy used for IT loads and the other half for cooling. The already voracious industry will have to consume ever-more power to keep pace with the growth in storage- and data-processing demand from the cloud.
But “you could maintain consumption at 2% of the grid and still double data-center capacity over the next five years if you deploy efficient technologies like the Inertech cooling solution,” Lee Kirby, vice president of strategic operations at Skanska USA, told Breaking Energy.
The solution is named eOPTI-TRAX. The patent-pending technology will go live on Aug. 15, when Canada’s third-largest telecommunications company, TELUS, brings on-line the data center Skanska has built for them in Rimouski, Quebec.
The brand name, which stands for “environmental optimization tracking system,” doesn’t convey the enormity of the energy and water savings promised by the technology. For example, deploying eOPTI-TRAX will slash the 90-watt expenditure for cooling a single server to 0.3 watts while eliminating at least 80% of overall water use, Inertech and Skanska executives said.
To understand how it’s possible to achieve such efficiency gains, it’s important to remember that chiller plants used for evaporative cooling systems “haven’t changed very much at all in the last 90 years,” said Inertech president and CEO Earl Keisling. He added that, all told, data centers relying on cooling towers to manage server heat are wasting “trillions of gallons of water a year.”
Another typical, data-center cooling technique, in which air conditioned air is blasted through the aisles of server racks, “is hardly an efficient way to cool the ‘hot aisles,’” Keisling told Breaking Energy. “But that’s the approach you often see in co-location facilities [which lease rack space to IT tenants]. They just want the racks up and running, and they hand the electric bills on to the tenants, so it’s not as if inefficiency is a problem for them.”
In the eOPTI-TRAX system, a wall of coolant distribution units stands within inches of the racks, neutralizing the heat released from the back of the servers. The refrigerant passing through a plenum is pumped outdoors to a coil where the heat is released to the atmosphere.
In a data center with 1,500 servers and an eOPTI-TRAX system , the CDU pumps would draw 500 watts. Conventional chiller systems, however, would draw 90,000 watts to cool the same number of servers while losing 4,300 gallons of water per day. The only water loss from eOPTI-TRAX systems occurs when the system expels refrigerant (water and glycol) because of solids accumulation.
We’re looking at a huge market in replacing the systems at existing sites and saving those buildings energy and water,” – Kiesling
Participants in analyst day experienced a 77-degree temperature in the “hot aisle” of a demonstration data center running load banks which simulated a server assembly drawing 130 kilowatts. “If someone told you that, on an 88-degree day, you could cool 130 kilowatts of load with 7 kilowatts of cooling energy, most people would say it’s impossible,” Keisling said. “But we’re doing it.”
When a sensor detects a pre-determined, outdoor “wet bulb” temperature, which is the lowest temperature attainable solely through evaporative cooling in a given humidity, the system turns on compressors co-located with the CDU’s to reduce refrigerant temperature.
“It’s basically a dry system from 59-to-69 ['wet bulb'] degrees, but you have a choice to be wet or dry from 69 ‘wet-bulb’ and up,” said Keisling, who spent 30 years designing and managing the installation of mechanical systems for New York City skyscrapers before joining Inertech.
In his presentation during analysts day, Jakob Carnemark, senior vice president of Skanska’s Mission Critical Center, stressed that his company is seeking flexibility in every aspect of its data-center designs.
Currently, he pointed out, data centers are built with “‘future-proof’ infrastructure” in anticipation of projected load increases. But “you’ll be under-utilized if you over-build,” Carnemark pointed out, explaining that Skanska offers scalable infrastructure to ensure maximum, overall efficiency over time.
Read additional Breaking Energy coverage of how siting data centers within Marcellus shale gas production zones could affordably provide fuel needed to meet soaring data center power demand here.
For example, the TELUS data center will go on-line as a 2.7 megawatt data center, but it will grow to 16 megawatts through a series of modular expansions.
Kiesling noted that Inertech plans to market its cooling technology beyond the data-center realm, targeting hotels, casinos and hospitals. “We’re looking at a huge market in replacing the systems at existing sites and saving those buildings energy and water,” he said.
Skanska’s Kirby told Breaking Energy that data centers consume 388 billion liters of water per year, and that the Intertech solution could reduce that consumption by 310 billion liters. “That’s a volume of water,” he observed, “equal to all the water that flows over Niagara Falls in three months.”