Nvidia's New Cooling System Reduces Data Center Water Use, But AI's Broader Problem Persists

Ekhbary News Agency | 2024-05-15

Nvidia recently introduced a warm-water cooling system, claiming it can significantly reduce water usage within data centers. An Nvidia executive, in a press release, stated this system could eliminate "pretty much all water usage" inside the facility. Josh Parker, Nvidia's chief sustainability officer, told Axios that "the water consumption challenge for data centers is largely solved."

The Incomplete Picture of AI's Water Footprint

This assertion, for all intents and purposes, addresses only a fraction of the total water story. As long as AI data centers rely on fossil fuels for power generation—a choice increasingly favored by tech companies—water savings cease at the data center's perimeter. Nvidia's measurement approach, which essentially draws a line around the facility, counting internal use while disregarding external consumption, is the core issue. This disparity highlights a crucial gap in the industry's approach to environmental responsibility, as water use in electricity generation and chip manufacturing can double or triple a facility's overall water footprint.

System Mechanics and Energy-Related Water Demands

The new system ingeniously pumps coolant into server racks at 45°C, exiting at 55°C, effectively transferring a substantial amount of heat away from the hardware. At this temperature, ambient air in most climates can dissipate heat through passive radiators, eliminating the need for evaporative cooling or, in some cases, fans. Such a fan-less, chiller-less data center would not only consume less water but also operate more efficiently and quietly. However, no data center functions without electricity, and many power plants are themselves significant water consumers. U.S. fossil fuel power plants, for instance, consume 2.7 billion gallons daily, primarily for cooling. Natural gas plants use 1.17 liters of water per kilowatt-hour, with coal plants requiring even more at 2.2 liters. These sources collectively supply about half of data center power today. While renewables offer a low-water alternative (0.01-0.03 liters/kWh), natural gas and coal are projected to meet over 40% of new electricity demand for data centers through 2030, according to the IEA.