Question

If you use your office computer 40 hours per week, and do not unplug the computer when it is not in use, how much carbon dioxide is produced from the “vampire energy” used by the computer in one year?

Answer 1

If you use a laptop:  9.25; a desktop with a CRT monitor:  55.51; a desktop with an LCD monitor:  46.26.

A laptop that is plugged up and turned off uses 0.001kw/hr of energy.  Each kwh of energy produces, on average, 1.39 lbs of CO2.  There are 24*7=168 hours in the week; subtract the 40 hour work week from this and we have 128 hours a week for 52 weeks a year:
0.001*128*52=6.656*1.39=9.25.

A desktop that is plugged up and turned off uses 0.004kw/hr of energy.  A CRT monitor uses 0.002 kw/hr when turned off.  This means we have:
(0.004*128*52*1.39)+(0.002*128*52*1.39)=55.51.

For a desktop and an LCD monitor, which uses 0.001 kw/hr of energy, we have:
(0.004*128*52*139)+(0.001*128*52*1.39)=46.26.