It is very easily measurable. In fact many rack UPS units (such as 2.2KW APC ones I use in my garage) even compute the carbon fooprint for you in their manageme

It is very easily measurable. In fact many rack UPS units (such as 2.2KW APC ones I use in my garage) even compute the carbon fooprint for you in their management web UI in pounds of CO2. The numbers can be surprisingly high, actually, even if you just have a few servers.