I bought a second hand mac Mini to use instead of my Mac Book, as I wanted to be able to use my laptop again ! I cannot vouch for power savings, but when I am not using the Mini I shut down the old PC monitor screen and let Weather Cat purr along in the dark 24/7.
Strange thing is, previously my Davis console and Mac Book were in my conservatory, probably about 40 or so feet from my ISS, and every day for 6 weeks I got a total comms failure which required W/Cat to be totally shut down and the Mac Book re-booted before it would work. This happened between 09:15 and 09:25 every day.
Got the Mini, it's in the lounge, 2 feet away from my mobile phone, about the same distance from my wireless router, I'm probably about 120 feet away from the ISS. Using the same cable from the console to the mini, and using Bluetooth keyboard and trackpad for the Mini, and a old Windoze PC monitor. So I'm breaking all the rules regarding electrical interference for the USB connection to the Console and so far in 45 days have not had a comms failure.
JC