stable diffusion will generate an image in ~30 seconds on an NVidia 3060, so the cost is on the order of cents per image, power use on the order of 170 watts during the generation, or 0.0014166666667 kwh. @ around 5 cents per kwh
You also have to calculate the life expectancy of the card against 30 seconds of its life as an ongoing cost.
Which is also on the order of 0.01c per query (answering 5 million queries in the lifetime of a $500 card).
Just ask ChatGPT what the cost is? ;)
Sure, but just remember that it can't do math, so any mathy answer it gives is just bullshit.