Water
AI Data Center Water Footprint Calculator
Estimate data center cooling water use thermodynamically from AI power load, PUE, evaporative cooling and cooling-tower operation.
Average electrical power used by AI servers and other IT equipment.
Total facility power divided by IT equipment power.
Use 100% for a fully evaporative heat-rejection assumption. Use a lower value for hybrid or partly dry-cooled systems.
2400 kJ/kg is a practical screening value near typical cooling-tower water temperatures.
Higher cycles generally reduce cooling-tower blowdown, subject to water chemistry limits.
Optional. Enter known cooling-tower drift loss; leave at zero if unavailable.
Optional Indirect Water Footprint
Optional water-consumption factor for electricity generation. Keep at zero to calculate onsite cooling water only.
Onsite Cooling Water Requirement
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Estimated cooling-tower makeup water over the selected operating period.
Energy & Heat
IT power load
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Total facility power
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Total heat rejection
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Evaporative heat load
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IT energy use
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Facility energy use
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Cooling Water
Evaporation rate
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Blowdown rate
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Drift rate
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Total makeup-water rate
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Total evaporation
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Total blowdown
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Total onsite makeup water
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Onsite water per IT kWh
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Total Water Footprint
Indirect electricity-related water
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Combined operational water footprint
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Method:
Total Facility Power =
IT Power x PUE
For this screening model, consumed electrical power is assumed to ultimately appear as heat requiring rejection.
Evaporative Heat Load =
Facility Power x Evaporative Heat Fraction
Evaporation Rate =
Evaporative Heat Load / Latent Heat of Vaporization
Because 1 kW equals 1 kJ/s:
Evaporation kg/hour =
Evaporative Heat kW x 3600 / Latent Heat kJ/kg
Water density is approximated as 1 kg/L, therefore kg/hour is approximately equal to L/hour.
Blowdown =
Evaporation / (Cycles of Concentration – 1)
Cooling Tower Makeup =
Evaporation + Blowdown + Drift
Onsite Water Intensity =
Total Makeup Water / IT Electricity Use
Optional Indirect Water =
Facility Electricity Use x Electricity Water Intensity
Combined Operational Water Footprint =
Onsite Makeup Water + Indirect Electricity-Related Water
The thermodynamic calculation estimates evaporative cooling-water demand. It does not imply that every data center uses evaporative cooling.
Air-cooled and dry-cooled data centers can have substantially lower onsite water consumption. Hybrid systems should use an appropriate evaporative heat fraction.
Actual cooling loads can also differ because of heat exported from the facility, heat recovery, climate, economizer operation, chiller performance and cooling-system configuration.