I am in Quebec, power is cheap to the point of this being irrelevant. Heating is also required a large part of the year (including until yesterday because the weather has been horrible so far this "summer"...). Plus, well, tax credit for business expenses make that "less than free".

> and how loud your racks are?

Watercooling and passive PSUs makes it silent. I hate noise.

> Can I ask what you're doing with that home lab

Beside all the usual services for a small business (phone, email, storage, backup, routing, etc), it is mostly an oVirt (RedHat Enterprise Virtualization) private cloud running Docker VMs used by the CI to compile C/C++, build embedded device firmware images and run tests. The extra horse power (and least power efficient) nodes are woken up use wake-up-on-lan and boot a template using PXE from the GlusterFS distributed NAS. They are shut down when the load goes down. Only the big 7U case with the double1 140mm watercooling fans is open all the time. It is the "head" of the cloud cluster (but in theory is configured to auto migrate in case of hardware failure to the dual 120mm 4U case, but honestly I never tried the automatic migration).

Not very pretty, but good enough. https://imgur.com/a/hnlInSz (yes, there is some overlap between those 2 pictures because I moved some units between taking them, some units have been traded for others too).