Data Center Water Use Calculator
Estimate daily and yearly cooling water from IT load and WUE, in liters and gallons.
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How to Use It
Enter the IT load, the site's water usage effectiveness and average utilization. The calculator estimates on-site cooling water per day and per year, with a household comparison for context.
How This Calculator Works
The calculator runs these formulas in your browser:
- Liters per day = IT load (MW) × 1,000 × 24 × utilization × WUE (L/kWh)
- Gallons per day = liters ÷ 3.785
- Gallons per year = gallons per day × 365
- Households = gallons per day ÷ 300
Default assumptions and sources
WUE is The Green Grid's water usage effectiveness metric (site water ÷ IT energy); see the LBNL page on the Green Grid WUE paper. The household figure uses EPA WaterSense's estimate of about 300 gallons a day used at home by an average American family.
Worked example
A 50 MW IT load at 80% average utilization uses 50,000 × 24 × 0.8 = 960,000 kWh a day. At a WUE of 0.5 L/kWh that is 480,000 liters, or about 126,800 gallons a day, roughly 46 million gallons a year and the daily home use of about 420 households.
Limits
It counts water used on site for cooling and humidity only, not the water used to make the electricity. WUE changes with the weather, so a yearly average hides summer peaks; size water supply from the cooling designer's peak-day number.
Common Questions
What WUE should I use?
Closed-loop and dry-cooled designs can be near zero. Evaporative systems in hot, dry places can use far more. If you do not know, try a few values to see the range.
Does this include water for power generation?
No. It counts water used at the site. Power plants that use water for cooling add an indirect footprint on top.
Why does utilization matter?
Cooling water tracks heat, and heat tracks how hard the servers work. A site at 50% utilization rejects roughly half the heat of one running flat out.