Get a power measuring device if you don’t have one and consider the real cost of buying something new if you already have something. For instance, I have an older gaming laptop I am considering repurposing for my home automation stuff. While idling it draws about 10w which is amazing to me and a number I never would have guessed. For me that works out to (24 hours * 10w * 365 days* 1000w/Kw ) 87kwh per year. I pay about 10 cents per kwh so say $10 a year. Buying something to save a little power will never work out.
My current home server is an intel NUC from 2013! It can’t do some of the things I would like to add on, but it is a great media server and downloader. Powerful hardware isn’t really a necessity.
Oof. I would buy more efficient hardware with those rates too!