I googled “intel mac pro electricity usage” and this was the top hit: https://support.apple.com/en-us/HT201796 https://support.apple.com/en-us/HT201796 The fir

I googled “intel mac pro electricity usage” and this was the top hit: https://support.apple.com/en-us/HT201796 https://support.apple.com/en-us/HT201796 The first (and highest) entry at 302W at idle would consume ~50% our household’s monthly usage. It’s at least the right order of magnitude.