>>coffee+(OP)
When I was mining with a bunch of RTX 3080s and RTX 3090s, the electricity cost (admittedly) was about $20/month per card. Running a 70B model takes 3-4 cards. Assuming you're pushing these cards to their extreme max, it's going to be $80/mo. Then again, ChatGPT is pretty awesome, and is likely running more than a 70B model (or I think I heard it was running an ensemble of models), so there's at least a ballpark.