Nvidia targets data center water use, but AI’s water problem remains

Nvidia has unveiled a warm-water cooling system that the company claims can slash data center water usage, with an executive stating in a press release that it eliminates “pretty much all water usage” inside the facility. Josh Parker, Nvidia’s chief sustainability officer, recently told Axios, “The water consumption challenge for data centers is largely solved.”

However, that assertion only tells part of the story. As long as AI data centers depend on fossil fuels,a reliance that tech companies are increasingly leaning into,the water savings stop at the facility’s perimeter.

The crux of the issue lies in how Nvidia calculates water use. According to its own blog post, the company draws a boundary around the data center. Everything within that boundary is counted; everything outside is not.

To give credit where it’s due, Nvidia’s system appears to deliver on its facility-level promise. The coolant operates in a closed loop, filled once and recirculated for the life of the facility, meaning no new water is consumed to cool the chips. In favorable climates, the company says this can result in a 100% reduction in on-site water use.

TechCrunch has reached out to Nvidia for clarification, and we will update this article if we receive a response.

The real problem is that water consumption outside the data center,primarily from electricity generation and chip manufacturing,can double or even triple the total water footprint of a facility. This means Nvidia’s solution addresses roughly a quarter to a third of AI data centers’ overall water usage.

The new system is clever in its design. It pumps coolant into racks at 45°C (113°F),too hot for humans but perfectly suited for computer chips. After passing through a server, the coolant exits at 55°C (131°F), carrying substantial heat away from the hardware, Nvidia explained.

At that temperature, outside air in most climates can dissipate heat through passive radiators without needing evaporative cooling or, in some cases, even fans. A data center without fans or chillers would not only use less water but would also be more efficient and quieter.

Yet no data center can function without an electricity supply, and many types of power plants are themselves major water consumers. Fossil fuel power plants are among the largest water users in the U. S., consuming 2.7 billion gallons per day, according to the U. S. Geological Survey,most of it for evaporative cooling. Natural gas plants use 1.17 liters of water per kilowatt-hour, according to a recent study, while coal plants are even more water-intensive, using 2.2 liters per kilowatt-hour. The International Energy Agency (IEA) reports that fossil fuel plants collectively generate about half of all data center power today.

Hydropower dams, which supply roughly 10% of data center power, don’t consume water in the same direct way, but evaporation from their reservoirs causes a loss of 6.8 liters per kilowatt-hour generated. Geothermal energy, which tech companies are beginning to explore, varies widely depending on the technology. Some enhanced geothermal startups, such as Fervo, have pledged to use mostly “degraded” water that would otherwise go unused.

In contrast, wind and solar power use vanishingly small amounts of water,about 0.01 liters and 0.03 liters per kilowatt-hour, respectively. These figures include the water needed for manufacturing and cleaning solar panels.

While renewables are providing a growing share of new electricity capacity, the IEA projects that natural gas and coal will still supply more than 40% of the new electricity needed to meet data center demand through 2030. Without major changes to that trajectory, data centers will continue consuming large amounts of water, no matter what Nvidia achieves inside its walls.