Earlier quoted context omitted.
That's true, there's a lot of places where power is considerably more expensive than $0.20 USD/kWh. But also the 600W figure assumes that it's fully loaded 24x7x365. Running a system that will be 600W under max CPU usage on all cores and RAM and a few 3090-class GPUs, that same system might be only 90W or around there when idle at 0.00 unix load. If we say: (600 * 24 * 31)/1000 = 446kWh in a month at full load 24 hou…
I think that's the biggest difference for most. If you can amortize the hardware costs, then 'burst usage' is cheaper at home to a degree, because you are paying a fixed monthly rate elsewise. Overall thought for most, it is likely cheaper to use the cloud than at home, but really depends on what you want.
No, you would pay usage based rates with API, in this case. I have exactly one fixed monthly rate for the 6 AI models I have tokens available for.