I managed to install xcp-ng and alpine on a Single Board Computer : seco b68 powered by Intel(R) Celeron(R) CPU N3350 @ 1.10GHz and 2GB of RAM !!!
https://mastodon.social/@rzr/114970751940254294
Then 400MB can be allocated for a VM (or several)
Let me track the power consumption and imagine some minimalist-homelab use-cases ...