Earlier quoted context omitted.
100% agree, anything beyond 4x gpu’s is getting into the very annoying to power territory and makes the cloud very attractive. I already can trip a 15A circuit on 115v power with just 3x4090s and a SPR-X cpu. It also costs a lot to power. In the summer, 2x more than you expect, because unless it’s outside, you need cool 1000+ watts of extra heat with your AC. All that together and runpod starts to look very tempting!
Getting that circuit installed was pretty cheap likely because its in an unfinished and unconditioned basement. The basement stays comfortable even during the summer. The heat does seem to work its way into the rest of the house but the additional cooling load is only about 20% more than usual. It lowers the heating cost about the same amount during the winter so it works itself out.
Getting a circuit put is also much more difficult in a shared building...
Runpod has 3090s for .43 per hour! .22 spot. If your power costs .3$ per kWh, and you need to spend _another_ .3$ per kWh in cooling, say if you live in apartment in the Bay Area and it's summer, that's ~48 days to equal the cost of 30 days on runpod. So you are still saving some money, though much less than you might think and possibly spending more than spot instances!