this post was submitted on 08 Sep 2026
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Fuck AI

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A place for all those who loathe AI to discuss things, post articles, and ridicule the AI hype. Proud supporter of working people. And proud booer of SXSW 2024.

AI, in this case, refers to LLMs, GPT technology, and anything listed as "AI" meant to increase market valuations.

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[–] isleepinahammock@lemmy.blahaj.zone -2 points 4 days ago (1 children)

The human brain runs on 20 watts of power.

That's not at all correct. Or more appropriately, it's a true number used in a completely incorrect context.

It actually takes about 100 kilowatts to 1 megawatt to maintain a human brain, depending on your assumptions. You can't power your brain with electricity; you have to power it with food. And you can't power just your brain, you have to power your whole body. And producing food takes a ton of energy, way way more than people realize. It's just that most of it comes free from sunlight with crops grown in open fields. But if we're really talking about the energy needs of humans vs AI, the competition is between using those fields to grow food for humans to eat vs using those fields to hold solar panels to power AI.

I get this 0.1-1.0 MW figure from the YouTube and Nebula channel, "Science and Futurism with Isaac Arthur." There it was used in the context of deep space exploration and colonization, not terrestrial AI deployment. If you want to estimate the power requirements for life support for a hypothetical interstellar spaceship (just life support, not propulsion), you multiply the assumed crew number by 0.1-1.0 MW. If you're traveling between stars you have to bring your own sunlight with you. The vast majority of that energy is just for the huge amount of light needed to grow the food people eat. Interestingly, this life support requirement would still be a rounding error compared to the energy needs for propulsion. But if you want to estimate how big of a reactor you would need to sustain all of a person's needs without free sunlight, 0.1-1.0 MW is a decent figure.

For you as an individual deciding whether to pay to power an AI vs doing something yourself, sure, the 20 watt figure has some merit. You're going to have to eat enough to live no matter what you do. Maybe you burn a few extra calories while thinking hard on a problem, but your calorie needs are mostly fixed.

But when we're talking about whether it's cheaper to hire large numbers of humans or build large numbers of data centers to serve the needs of the ownership class, you have to look at the actual raw power requirements needed to keep a human being alive. Plant growth is an incredibly inefficient process. But computers can be powered extremely efficiently by just plopping some solar panels down in a field.

[–] AgentSeven@lemmy.zip 2 points 4 days ago (1 children)

Well yes and if you wish to make an apple pie from scratch, you must first invent the universe. I think it can reasonably be said we're kinda spitballing here.

While I love Carl Sagan, you're doing him a disservice by using that quote here. When talking about whether human beings will be replaced by AI, you have to consider all the resources that go into maintaining both. You can't just hand wave that away by saying, "well, yeah, I guess, nothing means anything if you analyze it too deeply. Ultimately everything required the energy of the Big Bang, so we can't draw any real conclusions on the energy needs of anything. The world's just vibes bro."

We're not trying to get an exact figure. But when trying to predict whether AI will replace human labor, you have to make a reasonably fair comparison, otherwise your conclusions are completely worthless. Your entire point was that AI requires more energy to run than humans for a given task. If you think energy limitations are going to be the bottleneck for AI deployment, you need to make a fair comparison for the energy needs for both human and AI work.

Look at it this way. Let's say I have an acre of land. I want to turn that land into as much mediocre writing as possible. I could do two things:

  1. Use that land to grow food to feed mediocre human writers.
  2. Put solar panels on that land to produce electricity to power an LLM.

Inevitably, I would be able to produce thousands of times more mediocre writing from that same acre of land with option (2) than (1). Biology is stupidly inefficient from an energy efficiency perspective.