Water-Efficient Data Centers: a ‘Disruptive Solution’ to Drought

Data centers are a thirsty lot, guzzling huge amounts of water to support their cooling needs.

A modest 1 MW data center facility can easily consume more than 4.4 million liters (1.2 million gallons) annually, according to Emerson Network Power’s Jack Pouchet from, who also sits on the board of directors of The Green Grid, a nonprofit that promotes IT resource efficiency.

As cloud computing skyrockets and water scarcity worsens in many places globally, data centers are increasingly competing for a limited resource. A new ultra-efficient data center that opened last month in Plano, Texas, could be a game changer.

On Nov. 20, Aligned Data Centers, a division of Aligned Energy, opened its inaugural enery- and water-saving data center. With the first phase complete, the Aligned Plano data center offers 108,000-square feet of space and 12.5 MW of power. At full build, the site will provide 300,000-square-feet of space and 30 MW of power.

While similarly sized traditional data centers consume about 51 million gallons of water per year, the Aligned Plano data center utilizes an advanced cooling system that consumes up to 85 percent less water, the company says.

“It’s really a disruptive solution,” says Thomas Doherty, Aligned Data Centers chief operating officer. “There’s a tremendous amount of waste in traditional data centers.”

Rethinking Data Center Cooling

The traditional approach to data centers’ cooling systems is backwards, Doherty says: “People think you need to cool the data center. Really you need to remove the heat.”

The Plano data center uses systems manufactured by Inertect that rely on the company’s Conductive Cooling technology to remove data center heat. As Inertech explains on its website: In Conductive Cooling, a heat sink removes heat directly at the rack or aisle, creating a stable operating environment without the fluctuations or energy draw of cold air, and transports it away via an ultra-efficient Thermal Bus.

The system also pumps considerably less water for cooling, Doherty says. While a traditional system requires about 5.5 gallons per ton, the Aligned data center’s system uses about 1 gallon per ton. Plus the condenser water is only cooled to 65 degrees, compared to 45 degrees, which is used in most systems.

“Our systems are always using free cooling, even in the worst climates, we only use water when we need it, and ultimately the water we use in the pumping system is substantially less anyway,” Doherty says.

Energy Savings

In addition to the water savings, the Aligned Plano data center’s efficient power infrastructure guarantees a PUE (power utilization effectiveness) of 1.15. By comparison, most multi-tenant data center providers operate at a PUE of 1.3 or higher, the company says. The lower PUE translates into lower monthly power bills for customers.

Aligned Data Centers’ second such facility — a 550,000-square-foot, 69 MW data center in Phoenix, Arizona — is currently under construction and slated to open in June. Doherty says site selection for future facilities is underway in California’s Silicon Valley, Illinois, Virginia and New Jersey.

Conservation Challenges

As the demand for freshwater increases, other data centers are looking for ways to conserve. Vantage Data centers has minimized the amount of water-cooling needed at its three facilities in Santa Clara by installing air handling units that can pull outside air to cool the room. Meanwhile Digital Realty launched an internal water conservation challenge and is working with local water utilities to look into using recycled water at its facilities — similar to a system already in place in DuPont Fabros Technology’s Ashburn Corporate Campus in Virginia and one in the works for the National Security Agency’s data center being built at Fort Meade, Maryland.

“Many companies are working hard to minimize the environmental footprint of data centers,” says Daniel Castro, Information Technology and Innovation Foundation vice president. “One of the hardest challenges is providing sufficient cooling. There are a number of tradeoffs that companies can make to optimize cooling based on the climate where the data center is located, the available energy sources, and the cost of water. And overall, building data centers is a net positive for the environment as the economy becomes more digital.”

Water Usage Effectiveness

The Green Grid’s Pouchet says data center can become more water efficient by measuring and reporting their water usage effectiveness (WUE) at the core facility level. “As the old axiom goes: you cannot improve what you do not measure,” Pouchet says. “We highly recommend that all data center owners/operators measure and report not only PUE but also report WUE and CUE [carbon usage effectiveness.]”

Once owners/operators have begun measuring and reporting WUE, Pouchet suggests turning to the Green Grid Data Center Maturity Model (DCMM) for best practices and efficiency recommendations.

“This includes simple ‘upgrades’ most data center operators can make today such as hot-aisle (or cold-aisle) containment to improve airflow management and reduce cooling loads, increase the cold-aisle temperature set points, look to install some form of economization to the cooling system, install datacenter-wide monitoring and controls, consider an energy efficiency audit, identify and remove comatose/orphan/unused servers — recent studies indicate this could be up to 30 percent of the IT asset pool — upgrade to higher-efficiency servers, and consider joining industry organizations like the Green Grid where one can network with peers and gleam volumes of useful, hands-on, practical tips and insights saving time and money on your data center improvement project,” Pouchet says.

And when these tips translate into utility bill and operational savings that also conserve natural resources, everyone wins.