LucasFzt
im totally open to recommendations or ressources (only english or french please) about that, i'm fairly new to this topic
I am too, I only have one Rpi set up as a print server, no experience with hosting, but I bet if you google something like "cheap minecraft server" you should get some good tutorials. Other than that, depending on the CPU, you might be able to underclock and undervolt it a bit for lower power usage.