RESEARCH
Global Data Center Electricity Consumption for 2025 Splits Between 448 TWh and 860 TWh Across Trackers
Four major forecasters -- Gartner, the IEA, Deloitte, and S&P Global's 451 Research -- each published a full-year 2025 estimate for how much electricity the world's data centers consumed. Gartner and the IEA land close together at 448 TWh and 485 TWh. Deloitte and 451 Research land far higher, at 536 TWh and 860 TWh -- nearly double Gartner's number. All four agree consumption is surging on AI demand; they disagree by close to 100% on how large the base already is.
Findings
- Gartner (448 TWh) and the IEA (485 TWh) cluster within 8% of each other for full-year 2025 global data center electricity consumption.
- Deloitte (536 TWh) and S&P Global 451 Research (860 TWh) both run well above the Gartner/IEA cluster, with 451 Research nearly double Gartner's figure.
- The IEA separately reports 2025 data-center electricity demand grew 17% year-over-year, with AI-focused data centers alone surging 50%.
- The spread tracks methodology, not just forecasting error: grid-power-demand estimates (451 Research, S&P Global) run higher than metered-consumption estimates (Gartner, IEA), and scope of what counts as a data center is not standardized across trackers.
Delta Engine result
↔ Divergence Detected — Δ 0.2485 (threshold 0.05)
- IEA T5 95
- S&P Global (451 Research) T3 80
- Gartner T2 92
- Deloitte T2 74
Evidence quality
avg 68.8 · min 55 · max 95 · spread 40