Zeke Hausfather
Climate scientist whose measurements of AI energy use are among the few independent numbers available.
Zeke Hausfather is a climate scientist known for careful, data-first work on emissions and climate models, and for writing that explains the numbers rather than shouting about them. He publishes at The Climate Brink.
In AI circles he matters because he did something the industry mostly has not: measured. By logging eight weeks of his own AI agent use, 3.2 billion tokens in total, he produced an estimate that agent-style work draws roughly 600 times more electricity per prompt than the single-chat-query figures Google and OpenAI publish. His conclusion is deliberately unexcited, that this is both a large emissions source and a modest share of one person’s footprint, and that the decisive factor is whether data centres run on clean power, not whether individuals cut back.