I'm traveling in a rv and only generate 600w of solar max in the best conditions a few hours a day, the 4090 itself took 500w. For comparison sake, my 24v rooftop air conditioner takes between 350-1200w and my oven takes 1200-2000w, my fridge takes under 100w. I have 12kw total battery capacity (and I'm never at 100%). This of course isn't including all my lights, fridge, etc. And I don't run anything as much as my computer.
I game on my m1 max macbook pro now which is shockingly good at ~100wh.
I tried to make it make sense but it just doesnt. https://photos.google.com/share/AF1QipMRWCkjBSoFUpIKFbcPhds5... I have enough battery charging frustrations with the few things I do run daily.