GPT-4o Environmental Impact

Energy Consumption

GPT-4o consumes approximately 0.43 Wh per short query (100 input / 300 output tokens). Energy scales dramatically with context length: medium queries (~1,000 tokens each way) use approximately 1.2 Wh, while a 100K-token input can reach ~40 Wh. Sam Altman disclosed 0.34 Wh as an average; Epoch AI independently estimated 0.3 Wh; Jegham et al. measured 0.42 Wh (±0.13). We use the Jegham figure as it includes full infrastructure overhead.

Power Source & Carbon

OpenAI runs primarily on Microsoft Azure data centers, with key inference regions in US East (Virginia) and Sweden Central. Microsoft has contracted 34 GW of carbon-free electricity across 24 countries, but its location-based Scope 2 emissions doubled from 4.3M to ~10M metric tons CO2 between 2020 and 2024. The Virginia data center hub sits on a grid with approximately 450 g CO2/kWh carbon intensity — one of the dirtier grid regions in the US. OpenAI has also expanded to AWS and Google Cloud as of 2025.

Water Usage

Each GPT-4o short query consumes approximately 1.5 mL of water, based on Jegham et al. infrastructure-aware estimates. Sam Altman disclosed approximately 0.32 mL per query as an average. Water use scales with energy consumption — longer queries with more tokens use proportionally more. Microsoft's Azure data centers use evaporative cooling systems, though Microsoft has launched zero-water cooling designs in late 2024 to reduce this. Microsoft's average Water Usage Effectiveness (WUE) has improved 39% from 0.49 to 0.30 L/kWh between 2021 and 2024.

How much energy does GPT-4o use per query?

Each GPT-4o query consumes approximately 0.43 Wh of energy. This is about the same as a traditional Google search (~0.3 Wh).

What is GPT-4o's carbon footprint?

Based on the carbon intensity of Azure US East / Sweden, each query produces approximately 0.19 g of CO2. The grid in this region has a carbon intensity of 450 g CO2/kWh with 25% renewable energy.

How much water does GPT-4o use?

Each query consumes approximately 2 mL of water, primarily used for cooling the data centers that process the request.

How does GPT-4o compare to a Google search?

A GPT-4o query uses about the same as a Google search in terms of energy. A Google search uses approximately 0.3 Wh, while GPT-4o uses 0.43 Wh.

Architecture

Multimodal Transformer (decoder-only)

Context window

128,000 tokens

Release date

2024-05-13

Open source

No

Training data cutoff

2024-06