AI and climate
The emissions of AI depend first on the electricity that powers data centres. Google's total emissions have risen by 81% since 2019, Microsoft's by 58% since its 2020 financial year; these increases cover all of their activities, including AI.
By Projet Celsius
Focus areaAI emissions1.14gCO2efor a Le Chat answer of about one page, over the full life cycleMistral AI, July 2025Open the focus area →
Focus areaScenarios and uncertaintiesThe calculation methods, which put the same question at anywhere from 0.012 to 1.14 gram of CO2e.Open the focus area →
Focus area2030 trajectories458gCO2e/kWhfor one kWh of electricity in the world in 2025, over the life cycleEmberOpen the focus area →Charts and maps of the topic
Charts and maps →Focus area
ChartCompany · 2019 to 2025Google and Microsoft emissions+81%for Google, since 2019Google and Microsoft, 2026 reportsChartOne question · logOne question, 4 ways of counting CO2e0.3 Wh, France0.012Google, Gemini0.030.3 Wh, world0.14Mistral, Le Chat1.14 g92timesgap between the lowest and the highestEpoch AI; Ember; Google; Mistral AIChartCountries · 2025Server electricity, country by countryFranceWorldPoland589gCO2e/kWhPoland; France: 41.4Ember, 2026, via Our World in DataKey figureOne question · 2025Carbon footprint of one Le Chat response, life cycle1.14gCO2ea page of text, full life cyclethe same answer: 45 mL of waterMistral Large 2, with Carbone 4 and ADEMEMistral AI, July 2025ChartCompany · logElectricity emissions, by contract or by gridMetaGoogleMicrosoftdepending on the contractsdepending on the grid1 to 4,400the gap at MetaMeta, 2025; Google and Microsoft, 2026Key figureWorld · 2025Carbon intensity of world electricity458gCO2e/kWhLife cycle, AI Impact DatabaseEmber, 2026
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ChartWorld · 2023 to 2030AI emissions, comparedBelgium, 202498IA, 202599France, 2024367IA, 2030636Aviation, 2023882 Mt99MtAI in 2025, like BelgiumGreenIT; Eurostat; Citepa; ATAGChart2019 to 2023 dataThe digital sector in global emissionsThe Shift Project3.5 %GreenIT3.4 %Freitag et al.2.1 to 3.9%Malmodin et al.1.4 %Shift Project; GreenIT; Freitag et al.; Malmodin et al.Key figureFrance · 2025Carbon intensity of electricity in France41.4gCO2e/kWhLife cycle, electricity generatedEmber, 2026Chart2022 (January 2025 study)The digital sector in France, in 3 categoriesDevices14.6 MtData centres13.8 MtNetworks1.1 MtADEME, January 2025, 2022 dataKey figureFrance · 2022The digital sector's share of France's carbon footprint4.4%434 kgCO2e per person in France per year2022 data, 29.5 MtCO2eADEME, January 2025MapWorld · 2025The carbon intensity of electricityNorway 28France 41Poland 589gCO2e/kWh458gworld average, life cycleEmber, via Our World in Data
Analyses and articles
Analyses
Where does this figure come from?
Climate20 October 2026"Meta's electricity emits only 1,358 tonnes of CO2e"In 2024, Meta reports 1,358 tonnes of CO2e for the electricity it buys, the annual footprint of 170 people in France. The same report also gives 5.97 million tonnes. Both of the 2 figures are accurate.
AnalysisClimate12 November 2026Why do estimates of AI's impact differ?Calculated with French electricity, one question to an AI emits 0.012 gram of CO2e; Mistral AI publishes 1.14 gram, more than 90 times as much. Its water use ranges from 0.26 to 45 millilitres depending on the published measurements. These figures are accurate; they do not cover the same scope.On the Projet Celsius blog ↗
Sources for this topic
- Google, 2026 Environmental Report, June 2026 ↗
- Microsoft, 2026 Environmental Sustainability Report, Data Fact Sheet, July 2026 ↗
- Meta, 2025 Environmental Data Index, October 2025 ↗
- Epoch AI, How much energy does ChatGPT use?, February 2025 ↗
- Ember, Global Electricity Review 2026, and annual data via Our World in Data ↗
- Elsworth et al. (Google), Measuring the environmental impact of delivering AI at Google scale, August 2025 ↗
- Mistral AI, with Carbone 4 and ADEME, Our contribution to a global environmental standard for AI, July 2025 ↗
- Our World in Data, based on Ember, Lifecycle carbon intensity of electricity ↗
- GreenIT, Impacts environnementaux et sanitaires de l'intelligence artificielle dans le monde en 2025 et 2030, September 2026 ↗
- Eurostat, greenhouse gas emissions (env_air_gge) ↗
- Citepa, Secten 2026 report ↗
- ATAG, Facts and figures, aviation emissions 2023 ↗
- The Shift Project, Impact environnemental du numérique : tendances à 5 ans et gouvernance de la 5G, March 2021 ↗
- GreenIT, Impacts environnementaux du numérique dans le monde, February 2025 ↗
- Freitag et al., The real climate and transformative impact of ICT, Patterns, 2021 ↗
- Malmodin et al., ICT sector electricity consumption and greenhouse gas emissions - 2020 outcome, Telecommunications Policy, 2024 ↗
- ADEME, Évaluation de l'impact environnemental du numérique en France, January 2025 ↗
Across the hub
AI Impact DatabaseAll the figures, their methodology and their sources.
AI Ranking10 assistants rated out of 100: performance, ethics and environment.
AnalysesThe signed pieces: analyses, viewpoints, "Where does this figure come from?".
Charts and mapsThe reference visuals, with their data and sources.
ToolsOpen calculations, your assumptions on the left, the result on the right.
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