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wongarsuyesterday at 1:50 PM2 repliesview on HN

Each person uses about 100W (2000kcal/24h=96W). Running all of humanity takes about 775GW.

Sure, using or not using your brain is a negligible energy difference, so if you aren't using it you really should, for energy efficiency's sake. But I don't think the claim that our brains are more energy efficient is obviously true on its own. The issue is more about induced demand from having all this external "thinking" capacity on your fingertips


Replies

program_whizyesterday at 1:54 PM

Is there an AI system with functionality at or equal to a human brain that operates on less than 100W? Its currently the most efficient model we have. You compare all of humanity's energy expenditure, but to make the comparison, you need to consider the cost of replicating all that compute with AI (assuming we had an AGI at human level in all regards, or a set of AIs that when operated together could replace all human intelligence).

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Majromaxyesterday at 2:15 PM

I did some math for this particular case by asking Google’s Gemini Pro 3 (via AI studio) to evaluate the press release. Nvidia has since edited the release to remove the “tons of copper” claim, but it evaluated the other numbers at a reported API cost of about 3.8 cents. If the stated pricing just recovers energy cost, that implies 1500kJ of energy as a maximum (less if other costs are recovered in the pricing). A human thinking for 10 minutes would use sbout 6kJ of direct energy.

I agree with your point about induced demand. The “win” wouldn’t be looking at a single press release with already-suspect numbers, but rather looking at essentially all press releases of note, a task not generally valuable enough to devote people towards.

That being said, we normally consider it progress when we can use mechanical or electrical energy to replace or augment human work.