Summary
Data centers need lots of water for cooling and electricity generation, but the full picture of where and when this water is used isn’t well understood. The authors created a model that tracks both the direct water used on site and the indirect water used by power plants supplying electricity. They found that choosing air cooling over evaporative cooling cuts water use at the data center but increases electricity use, shifting water consumption to different locations and times. This means water impacts must be studied beyond the data center itself to make smarter decisions about where and how to build and cool these facilities.
What this means in practice
- •For data center planners: Plan data center locations and cooling systems with detailed regional and hourly water use impacts to reduce overall water risk.
- •For energy grid operators: Incorporate data center loads into dispatch decisions to better account for water use impacts across specific power plants and watersheds.
Abstract
Data centers are being developed at an unprecedented pace, yet their energy and water impacts, and the spatial and temporal distribution of these impacts, remain poorly characterized. Data centers consume water for cooling (direct) and through electricity generation (indirect). Decisions on siting and cooling technology result in water-energy trade-offs that extend impacts beyond the facility's location. Existing assessment frameworks rely on facility efficiency metrics and average grid water intensity factors, suppressing the temporal impacts of data center load and generation availability. They also attribute indirect consumption to the facility's location rather than to the generators (and corresponding hydrologic regions) that respond to the added load, misattributing spatial impacts. To close this gap, we develop a computational model of the data center-energy-water nexus that links facility cooling and electricity demand with hourly economic dispatch, generator-level water consumption, and monthly subbasin depletion. Built on open-source data, the model resolves where and when water is consumed, and where this consumption compounds existing water risk or creates new risk. Using the model, we study different cooling configurations and proposed developments in the state of Michigan. Air-cooled data centers halve total water consumption relative to evaporative cooling, but increase electricity demand and raise indirect water consumption by one-third, shifting the water footprint from the facility to generators. Mapping these changes to subbasins reveals depletion increases beyond the data center sites, in regions that facility-level reporting may overlook. These results show that data center water and energy impacts cannot be assessed in isolation, motivating the need for integrated modeling to inform siting, design, and reporting practices.