Resource Usage (PUE)

Efficiency and carbon metrics · PUE, emissions and disclosure

The average data center spends about half again its IT power on overhead, a figure that has barely moved since 2019. Hyperscale AI campuses run far leaner, near 1.1, but their total emissions are rising with AI, and the EU and California now require operators to report.

Power usage effectiveness compared: industry average 1.52, size-weighted 1.36, AWS 1.15, Google 1.09 and NREL ESIF 1.036, against Germany's 1.2 cap for new data centers; and hyperscaler water use per kWh PUE: FACILITY POWER PER UNIT OF IT POWER 1.0 = NO OVERHEAD 1.0 1.2 1.4 1.6 Germany: 1.2 cap, new sites Industry average, 20261.52 Size-weighted average1.36 AWS fleet, 20241.15 Google fleet, 20251.09 NREL ESIF, warm water1.036 WATER: LITERS PER KWH OF IT ENERGY (WUE) Microsoft, FY20240.30 Meta, 20240.19-0.20 Google reports total water use (up 34% in 2025), not WUE. Water use is covered in detail on the Cooling pages.
Industry PUE
1.52
Google PUE
1.09
Germany new-site cap
1.2
EU ratings
From 2027
Hub
Energy

PUE

PUE Has Stalled Industry-Wide but Not at Scale

  • Industry: the Uptime Institute's 2026 survey puts the average at 1.52, barely changed since 2019 (1.54 in 2025). Weighted by facility size it is 1.36, and new large facilities routinely report 1.3 or lower.
  • Hyperscalers: Google 1.09 (2025) and AWS 1.15 (2024); Microsoft's and Meta's current fleet figures were not found in their latest reports.
  • Best case: NREL's ESIF in Colorado runs at 1.036 on warm-water liquid cooling and heats its own building. See Heat Reuse.
  • Caps: Germany requires 1.2 or lower for new data centers from July 2026, 1.5 for existing sites by July 2027 and 1.3 by 2030, and 100% renewable electricity from 2027.

PUE measures overhead, not total energy: a campus can hit 1.1 while its total draw grows tenfold. See Scaling Data Center Energy.

Carbon

Hyperscaler Emissions Are Rising With AI

  • Google: data center electricity rose about 37% in 2025 to about 42 TWh; Scope 1 and 2 emissions fell 2% while supply-chain emissions rose 25%; hourly carbon-free share slipped to 65%. Its 2030 goal of 24/7 carbon-free power stands.
  • Microsoft: emissions rose from about 13 Mt CO2e in 2020 to about 20 Mt in 2025, roughly 50%, and Microsoft paused buying unbundled renewable certificates; its carbon-negative-by-2030 goal is unchanged. New designs since August 2024 use no evaporative water for cooling, with a nominal energy penalty.
  • Meta: 100% of electricity matched with clean energy since 2020; location-based emissions rose in 2024.

Reporting rules

Ratings and Disclosure Arrive in 2027

  • EU: the Commission adopted a mandatory A-to-G rating for data centers of 500 kW and up in September 2026, grading PUE, water use, energy sourcing, grid flexibility and heat-reuse readiness; first labels in 2027 and minimum standards proposed for mid-2027.
  • California: AB 1577 (September 2026) requires operators to report location, size, PUE and onsite generator fuel to the state energy commission.
  • New Jersey: a 2026 law requires data centers to disclose energy and water use every six months.

Record

Dataset Record

Dataset
PUE, carbon and water metrics for data centers and hyperscalers
Sources
Uptime Institute, Google, Microsoft, Meta, Amazon, NREL, EU Commission, California and New Jersey legislation, White & Case, Linklaters, DatacenterDynamics, The Register, S&P Global
Last verified
October 2026