back of the napkin
I’m just tossing out numbers to give me something to think about.
Searching ‘human body watts’ gives us 100 watts. Even better, it comes from a paper titled The 20 W Sleep Walkers by the National Institute of Health. More specifically, PubMed Central, National Library of Medicine, National Center for Biotechnology Information. (“20 Watt Sleep Walkers” would be a great band name.)
Anyway, estimates range from 70 watts resting to 300-400 watts during physical exertion.
1 watt = 1 joule per second. Not important for now, but fiddling with time gives us varying amounts of energy.
Average electricity cost in the US is around 15 cents per kilowatt hour. 1 kilowatt = 1000 watts, 100 watts = 0.1 kilowatts = 1.5 cents per hour. …times 24 hours = 36 cents per day? That seems way too cheap.
Boston Dynamics’ Spot - Typical runtime of 90 minutes. Power supply output 400 watts, charging takes ~1 hour, dock charger 2 - 3.5 hours depending on temp.
So 400 watt hours for 90 minutes. Round way up to 300 watts. Hmmm. Not bad, if correct.
ATLAS - has a 3.7 kWh for 1 hour of ‘mixed mission’ use. So, 3700 watts? That’s a lot, but not unreasonable considering it’s 345 pounds. Also depends on what ‘mixed mission’ means. So, if you had enough robots, you could have 24 hour usage for less than $15 a day.
Hmmm. taking a different approach, just an edge computing AI camera can run about 2 watts with up to 2 TOPS (not sure if If TOPS will play into this later on).
I can’t find any good numbers regarding required processing power required for image recognition, and autonomous reaction to images. Specifications for autonomous vehicles are all over the place. Global Semiconductor Alliance ranks autonomous vehicles as 2 TOPS for L2 autonomy, 24 TOPS for L3, 320 TOPS for L4 and 4,000+TOPS for L5.
…They don’t specify what the L levels mean. As of spring 2025 the highest ranked component I can find comes in at just over 2600 TOPS. Hardware with 40 TOPS is considered “AI-capable”.
Current TOPS per watt reports and estimates vary widely - 25 TOPS/W should be safe considering the other calculations going on here.
A typical nuclear power plant produces 1000 megawatts (1 Gigawatt) of electricity and takes 5-6 years to build after red tape and permits are done. The average geothermal power plant produces ~40 megawatts, one of the largest has a 1500 megawatt capacity. They take 5-6 years to build after red tape and permits are done.
Ooooh, put a huge AI data center in a nuclear power plant without radiation hardening. Given how much they hallucinate already, Toxic Avenger AI could be a thing.
Anyway, back on track…