Pedantically, sysadmins always counted the power consumption (or, compute density) when upgrading servers, and would even do early upgrades as a cost saving mea

Pedantically, sysadmins always counted the power consumption (or, compute density) when upgrading servers, and would even do early upgrades as a cost saving measure. Power costs (in datacenters at least) were high enough that buying the €10,000 server that sucked 200w more was worth less than the €15,000 machine that didnt suck that extra 200w. So electricity prices can be more than a negligible amount on the total. Where that line is depends on your personal situation. I live in southern sweden and they hide the total price of power here, but aggregated my cost per watt is 5sek/kWh (roughly €0.45). So a worst case for me at 200w with 24hrs of usage is about €800/y