On Wed, Jul 29, 2026 at 11:42:50AM +0000, Jaro Reinders via ghc-devs wrote: > It lists the data center efficiency (pue) as 1.12, gpu power usage > (pgpu) as 5.6 kW, non gpu power usage (pngpu) as 4.6 kW, lower bound > on gpu utilization (ugpu) as 0.055, and non gpu utilization (ungpu) > as 0.0625. > > Using the formula E = pue * (pgpu * ugpu + pngpu * ungpu), we find > that GPT 5 uses about 0.67 kW to run
But how many users is it serving? Does "utilization" imply "utilization per concurrent user"? Even if so, bear in mind that one concurrent user is not one *actual* user! > but the CO2e/kW of GPT is also higher at 0.34. We come to 228 grams > CO2e per hour, or about 15000 hours (less than two years of > continuous use) for a transatlantic return flight equivalent. But people don't work 24 hours a day. A rough working year is 2000 hours, so this is still 7.5 years' worth of work. But I suspect that might be to serve *one concurrent user*. Most users are nowhere near fully saturating the capacity of an LLM endpoint. > It is not quite a return flight every year, but also not a once in a > lifetime thing Maybe, maybe not. I don't think the analysis has definitively determined that yet. I understand you may want to err on the side of caution. That is your right. You also may want others to err on the side of caution. It would be preferable to have hard data so that we don't have to err! > especially if you start using multiple agents at once. Indeed. The total energy use and carbon emissions of agentic coding will rise. Tom _______________________________________________ ghc-devs mailing list -- [email protected] To unsubscribe send an email to [email protected]
