Water for one question, from 0.26 to 50 mL depending on scope
Water attributed to a written question to an AI, in millilitres (logarithmic scale)
Water for one question, from 0.26 to 50 mL depending on scope
Sources
Source: Google; OpenAI; UC Riverside; Mistral AI. projetcelsius.com/en/ai · CC BY 4.0- GoogleElsworth et al. (Google), Measuring the environmental impact of delivering AI at Google scaleAugust 2025 (new tab)
- OpenAISam Altman (OpenAI), The Gentle SingularityJune 2025 (new tab)
- UC RiversideLi, Yang, Islam and Ren, Making AI Less "Thirsty"2023 (new tab)
- Mistral AIwith Carbone 4 and ADEME, Our contribution to a global environmental standard for AIJuly 2025 (new tab)
The analysis
- A factor of about 190 separates the lowest, 0.26 mL (Google), from the highest, 50 mL (UC Riverside): it comes from scope and task, not from a calculation error.
- Google counts the water evaporated to cool its data centres; Mistral adds the water of electricity and of server manufacturing.
- "A bottle of water per email" comes from a 2024 Washington Post article that we could not check at source (paywalled): its figure is neither plotted nor reused here.
The figures
- Google, Gemini (on-site cooling, measured): 0.26 mL.
- OpenAI, ChatGPT (declaration, no method): 0.32 mL.
- UC Riverside, GPT-3 (cooling and electricity): 10 to 50 mL.
- Mistral AI, Le Chat (full life cycle): 45 mL.
Assumptions
- Water consumed, under 4 different scopes.
- 4 studies, 4 different models and 4 different tasks.
- Withdrawing and consuming water are not the same thing; the water stress of the location matters more than the volume.
More on water
The whole Water topic →Charts and maps
Chart
WaterMicrosoft's water use, 2020-202550%of withdrawals in financial year 2025 in water-stressed areasMapWaterWater stress, country by country17.6%world average in 2023Key figureWaterWater for one question to GeminiMedian · written question · Google measurement, August 2025Key figureWaterWater consumed by the world's data centresWorld · per year, in 2023 · water consumed, direct and indirect · IEA
WaterMicrosoft's water use, 2020-202550%of withdrawals in financial year 2025 in water-stressed areasMapWaterWater stress, country by country17.6%world average in 2023Key figureWaterWater for one question to GeminiMedian · written question · Google measurement, August 2025Key figure
WaterWater consumed by the world's data centresWorld · per year, in 2023 · water consumed, direct and indirect · IEA
Analyses
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