Google: the best disclosure in the index, attached to the worst trend

What Google publishes

More than any other company in the index. A measured per-prompt footprint with a published methodology (0.24 Wh, 0.03 gCO₂e, 0.26 mL for the median Gemini Apps text prompt in May 2025, with a narrower 0.10 Wh active-chip figure alongside). An annual environmental report with location- and market-based Scope 2, total electricity (about 43 TWh in 2025), hourly carbon-free share (66%), freshwater consumption (10.9 billion gallons) and replenishment (about 78%). A fleet WUE of 1.15 L/kWh, disclosed in the inference paper. A circularity page with 8.8 million components harvested. Seven of the nine items on the disclosure checklist are met in full.

What the numbers show

Electricity consumption rose 37% in 2025, the largest increase Google has reported, to roughly 3.5 times the 2019 level. Total emissions rose 18%, almost all of it Scope 3 from chip manufacturing, logistics and data-centre construction, while operational emissions fell 2%. Freshwater consumption rose 34%. Energy per median prompt fell 33× over twelve months; the fleet grew faster than the prompts got cheaper.

How the pillars land

• Efficiency 90: the measurement is the best in the field, self-reported and not independently verified.
• Carbon 60: 100% annual renewable matching for nine years and a 24/7 goal for 2030, against absolute emissions 51% above 2019 by 2024 and rising.
• Water 55: a disclosed WUE and a serious replenishment programme, against rising consumption, an evaporative design and the history at The Dalles.
• Transparency 82: no training-emissions disclosure for Gemini and no third-party review of the inference study.
• Commitments 80: net zero across operations and value chain by 2030, 24/7 carbon-free energy on every grid by 2030, 120% replenishment.
• Conduct 55: funded a city's lawsuit to withhold water records, then reversed and now backs reporting standards.

The scale

Epoch AI estimates Google holds about a quarter of the world's AI compute, roughly 5 million H100-equivalents, around 4 million of them TPUs. The index's hardware block derives about 2.6 million tonnes of embodied CO₂e, 87,000 tonnes of future e-waste and 132,000 tonnes of copper from that fleet.

The verdict

Second place at 71 is where the index puts a company that shows its working and whose working shows a footprint growing faster than it is cleaned. Google's own chief sustainability officer wrote the sentence that summarises the profile: the AI build-out is outpacing grid decarbonisation.