A cheat sheet for why using ChatGPT is not bad for the environment
A cheat sheet for why using ChatGPT is not bad for the environment
The idea that personal LLM use is environmentally irresponsible shows up *a lot* in many of the online spaces I frequent. I've [touched on my doubts around this](https://simonwillison.net/2024/Dec/31/llms-in-2024/#the-environmental-impact-got-better) in the …
If you want to prompt ChatGPT 40 times, you can just stop your shower 1 second early. [...]
Notably, Andy's calculations here are all based on the widely circulated higher-end estimate that each ChatGPT prompt uses 3 Wh of energy.
So, 1s of shower is supposed to be 40*3Wh, or 120Wh? That's, what, a 432000W heater? I'm not running a small nuclear power plant to shower in the morning.
- Specific heat capacity of water: 4.184J/(gC)
- Average shower temperature: 37C
- Cold tap water temperature: T
- Shower head output: 2gallon/min = 7.57L/60s = 126ml/s = 126g/s
1s * (126g/s) * (4.184J/(gC)) * (37C - T) = 524J/C * (37C - T)
120Wh = 432000J
T = -787C
So I guess the math checks out if your city's water supply temperature is way below absolute zero.
Scratch that, let's assume the water actually flows, so T=0C. What water throughout do we need to achieve this level of power consumption?
1s * (X g/s) * (4.184J/(gC)) * (37C) = 432000J
X = 2791g/s = 44gpm
You would have to be showering with 17 showerheads simultaneously using showerheads that are rated at the highest legal flow rates in the US (2.5gpm).
What, you don't shower with 800C steam?