Are big tech companies’ emissions going up because of AI?
The claim: “Big tech’s emissions are rising because of AI.”
Their emissions are rising, by their own 2026 reports. Google’s emissions counted toward its climate goal rose 18% in 2025, to about 14.5 million tonnes of CO₂e, 81% above 2019, while its electricity consumption grew 37%. Its electricity-related (scope 2) emissions fell 3%. Microsoft’s total emissions rose 25% in its 2025 fiscal year, to 20.29 million tonnes, mainly from expanding its data centres and no longer counting renewable certificates that add no new power. Neither company says how much of the rise is AI.
The bigger pictureAll the world’s data centres, of which AI is one part, used about 485 TWh in 2025. That’s about as much electricity as France uses in a year, and around 1.5% of the world’s. The IEA expects it to roughly double by 2030.
Why the claim misleads
That emissions are rising is true. That AI is the cause is the part the companies don’t break out.
What nobody knows yet
- Neither company separates AI from its other data-centre work.
- Google’s figure counts only the emissions inside the boundary of its climate goal; its full footprint is larger.
- Microsoft’s figure uses its own “management’s criteria” for some supply-chain emissions; its strict Greenhouse Gas Protocol total for the same year is higher.
- These are the companies’ own figures, only partly reviewed by outside auditors.
Sources (7)
- Google, 2026 Environmental Report Company says so
“In 2025, our total ambition-based emissions were approximately 14.5 million tCO2e, representing an 18% year-on-year increase and an 81% increase compared to our 2019 base year”
Quote checked on the page, 25 Oct 2026 - Google, 2026 Environmental Report Company says so
“Compared to 2024, our scope 2 (market-based) emissions decreased by 3% despite a 37% year-over-year increase in total electricity”
Quote checked on the page, 25 Oct 2026 - Microsoft, 2026 Environmental Sustainability Report (fiscal year 2025) Company says so
“Our total emissions (Scopes 1, 2, and 3) increased 25% year over year, driven primarily by the expansion of our datacenter infrastructure and stopping our use of non-additional, unbundled renewable energy certificates”
Quote checked on the page, 25 Oct 2026 - Microsoft, 2026 Environmental Sustainability Report (fiscal year 2025), emissions chart in metric tons CO2e Company says so
“Emissions FY20 12,881,000 FY21 13,772,000 FY22 13,635,000 FY23 16,112,000 FY24 16,215,000 FY25 20,290,000”
Quote checked on the page, 25 Oct 2026 - IEA, Key Questions on Energy and AI (2026) Estimated
“electricity consumption from data centres roughly doubling from 485 TWh in 2025 to 950 TWh in 2030”
Quote checked on the page, 3 Oct 2026 - Ember, yearly electricity data (CSV, CC BY 4.0) Data row
Data row: France, 2025, electricity demand 480.6 TWh. Demand includes grid losses, so it is close to, not the same as, consumption.
Row checked against the published file, 6 Oct 2026 - IEA, Energy and AI (2025) Estimated
“Data centres accounted for around 1.5% of the world’s electricity consumption in 2024, or 415 terawatt-hours (TWh).”
Quote checked on the page, 3 Oct 2026
Hum’s sums
- Microsoft’s fiscal 2025 total, 20,290,000 tonnes of CO₂e, is 20.29 million tonnes.
Cite this
Google, 2026 Environmental Report, as quoted in Hum, “Are big tech companies’ emissions going up because of AI?”, https://humearth.org/q/big-tech-emissions (quote checked 25 Oct 2026).
Cite the original source first; Hum is where you found it.
What do Wh, kWh and TWh mean?
Wh is a watt-hour: a 1-watt light left on for an hour. 1 kWh = 1,000 Wh, and 1 TWh = 1 billion kWh. Hum compares each number with something everyday so you don’t need the units.
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By their own reports: Google’s emissions rose 18% in 2025 (electricity use up 37%), Microsoft’s 25% in fiscal 2025. How much is AI, they don’t say.