Rather than wax on about all the many things that impacted our industry this year and will shape it going into 2023, let’s focus on a big one: the shrinking availability of water.
Most of us look back on the summer of 2022 with more than a little exasperation. It was unbearably hot in much of the world, with historic heat waves and widespread drought. Summer 2022 ranks among the hottest on record, according to data from NASA and the National Oceanic and Atmospheric Administration (NOAA). Summers have warmed by 0.47°F degrees Fahrenheit per decade since 1980.
In response, municipalities across the globe issued water restrictions. In Texas, where we like our St. Augustine grass lush and tend to water a lot, that saves about 700 gallons per household each day watering is restricted. Meanwhile, the 15 — MW data center down the road is using 6.7 million gallons per MW annually, making them prime cap targets.
Even without environmental change, the world is consuming water at ever-faster rates. Global population has doubled over the past 40 years, but waster usage has quadrupled. The Water Resources Group forecasts global water demand may outstrip sustainable use by 40% as soon as 2030.
The pressure is on
The attention once given to energy usage — prompting the shift and massive expansion of microgrids powered by renewable resources — is now on water. The movement toward more sustainable cooling options is taking place amid increased restrictions on the use of refrigerants. It’s no small challenge to come up with better ways to use water in both sourcing and design.
On the sourcing front, some hyperscale facilities are starting to include on-site water treatment facilities to tap into local, non-potable water sources. In places like Singapore, non-potable water usage is mandated for water-cooled systems.
On the design front, more providers are choosing cooling systems with minimal need water requirements. Others are incorporating rainwater recovery strategies to capture rain, store it on-site, and use it for cooling to reduce burden on local water supplies.
Solutions abound
Since its inception, Compass Datacenterhas used a waterless airside cooling design. Free and 100% renewable, air is drawn into the facility through finely calibrated filters (to remove particulates) and used to cool the facility. Sure, certain areas of the country have more “free cooling” hours than others, but there is virtually nowhere in the country where it hasn’t been successful in minimizing water consumption. Even in the heat of Houston, we’re getting more than 3,600 hours of free cooling annually.
A review of corporate sustainability reports from some of the largest data center operators shows a wide variety of solutions in the works to minimize water use at the facility and maximize water availability for neighboring communities. Some ways of achieving this are listed below.
- Expanding the use of non-potable and recycled water for cooling.
- Routing clean cooling water to farmers for additional application in irrigation.
- Optimizing relative humidity.
- Installing adiabatic cooling systems, which use less water than evaporative cooling systems.
- Piloting higher server inlet temperatures to reduce cooling hours and water use.
Testing new technology
Liquid immersion cooling, being tested for potential use in data centers, is showing some exciting results. It involves placing servers in a tub of inert fluid that boils at 122°C, which removes the heat generated by the chips, servers, and power supplies, and condenses the fluid in coils at the top of the rack to rain back into the tank. Tests found that some chipsets showed a 20% improvement in performance with liquid cooling. This could have the potential to impact not only water use but rack design and increased data center capacity.
That is all to say, there is some really cool work being done. Our industry is rising to the challenge of hotter temperatures and limited water supplies. Just as we managed to minimize energy demand while global internet traffic expanded, we’re going to innovate to positively impact water availability. I’m excited to be along for the ride and proud of how the industry is responding.
