Why Nvidia’s water-saving tech doesn't solve AI’s water problem

Nvidia has announced a new warm-water cooling system for data centers, aiming to tackle the heavy resource demands of artificial intelligence infrastructure. Josh Parker, the chief sustainability officer at Nvidia, recently told Axios that “the water consumption challenge for data centers is largely solved.” According to an Nvidia executive, the newly introduced system can pretty much eliminate all water usage inside the data center facility itself.

The system operates by pumping coolant into server racks at 45°C (113°F) and removing it at 55°C (131°F) as it draws heat away from the hardware. Nvidia claims the technology can achieve a 100% reduction in on-site water use in favorable climates.

However, this solution only addresses water consumption inside the facility, leaving the broader environmental impact of the energy grid untouched. Water use outside the data center can double or triple the total water footprint of a facility. In the U.S., fossil fuel power plants consume 2.7 billion gallons of water per day, according to the U.S. Geological Survey (the U.S. government agency focused on natural sciences), primarily for evaporative cooling.

The water intensity of electricity generation varies widely depending on the power source:

• Natural gas: Power plants burning natural gas use 1.17 liters of water per kilowatt-hour of electricity they generate.
• Coal: Coal plants are even more water-intensive, consuming 2.2 liters per kilowatt-hour.
• Hydropower: Dams supply around 10% of data center power, but evaporation from their reservoirs accounts for 6.8 liters of water lost per kilowatt-hour generated.
• Wind and solar: These renewable sources use vanishingly small amounts of water, requiring just 0.01 liters and 0.03 liters per kilowatt-hour, respectively.
• Geothermal: This alternative source, associated with startups like Fervo, varies widely.

Currently, fossil fuel power plants generate about half of all data center power, according to the International Energy Agency (IEA). This reliance is unlikely to shift rapidly; the IEA projects that natural gas and coal are expected to provide more than 40% of the new electricity needed to meet data center demand through 2030. Without a fundamental shift in how data centers are powered, the industry’s total water footprint will remain substantial, regardless of efficiency gains inside the server room.

Why it matters

Nvidia’s new cooling system addresses on-site water usage, but critics argue it fails to account for the significant water footprint associated with the electricity generation required to power AI data centers. As long as the infrastructure relies on fossil fuels, the environmental savings remain confined within the facility’s walls.