Nvidia unveils a warm-water cooling system that eliminates on-site water use in data centers
Nvidia has introduced a new warm-water cooling system claiming to remove nearly all water consumption from the data center itself. Josh Parker, chief sustainability officer at Nvidia, told Axios that the water consumption challenge for data centers is largely solved.
That claim holds true only within the facility boundaries. The solution does not address the water required to generate the electricity powering the servers or to manufacture the chips inside them.
Scope of the measurement
Nvidia defines its water footprint by drawing a line around the data center. Anything inside counts; anything outside is excluded. The company’s blog post confirms the system works as promised at the facility level. Coolant runs in a closed loop filled once and recirculated for the life of the facility. Nvidia says this delivers a 100% reduction in on-site water use in favorable climates.
However, water use outside the data center — mainly in electricity generation and chip manufacturing — can double or triple the total water footprint. Nvidia’s approach addresses roughly a quarter to a third of the total water consumption for AI data centers.
How the system works
The technology pumps coolant into server racks at 45˚ C (113˚ F). This is hot for humans but safe for computer chips. After passing through a server, the coolant exits at 55˚ C (131˚ F), carrying significant heat away from the hardware. At that temperature, outside air in most climates can remove the heat via passive radiators. This removes the need for evaporative cooling or fans in some cases. A data center without fans or chillers would use less water, run more efficiently, and be quieter.
Every data center requires an electricity supply, yet many power plants are major water consumers.
Power generation water use
Fossil fuel power plants rank 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 this water supports evaporative cooling. Natural gas power plants use 1.17 liters of water for every kilowatt-hour of electricity generated, based on a recent study. Coal plants are even more water-intensive, using 2.2 liters per kilowatt-hour. Fossil fuel power plants collectively generate about half of all data center power today, according to the IEA.
Hydropower dams supply around 10% of data center power. While they do not consume water directly in the same way, evaporation from their reservoirs results in a loss of 6.8 liters per kilowatt-hour generated. Geothermal energy, which tech companies are beginning to explore, varies widely depending on the specific technology. Some enhanced geothermal startups, like Fervo, have pledged to use mostly “degraded” water that would otherwise go unused.
Wind and solar power use vanishingly small amounts of water. Wind uses about 0.01 liters per kilowatt-hour, while solar uses about 0.03 liters per kilowatt-hour. These figures include the water needed for manufacturing and cleaning solar panels.
Future electricity mix
Renewables are providing a growing share of new electricity capacity. However, the IEA projects that natural gas and coal are expected to provide more than 40% of new electricity needed to meet data center demand through 2030. Without major changes to that trajectory, data centers will continue to consume large amounts of water regardless of Nvidia’s improvements inside the facility walls.
What it means
For people building and running AI systems, this news clarifies that efficiency gains inside the server room do not equal a reduction in overall environmental impact. The water footprint of an AI model depends heavily on where the electricity comes from. Until the power grid shifts away from fossil fuels, the total water cost of training and running AI remains high.
