Engery use of a PC?

Question

I am trying to find out how much my dell optiplex pc uses in terms of energy at the office.
It has a 17" CRT, and 2Ghz intel P4. lets say it runs ( ie srfing email, and reading, nothing processor intensive) for 8 hrs per day and on standby for the other 16, can anyone give an idea of the engery cost?
I used this site and got an answer of $800 per year, which seems kinda much?
http://www.eu-energystar.org/en/en_007c.shtml

Answer 1

If you want an accurate method, connect a "current meter" into the system and see how much the PC and accessories used when being used.

assuming a 230V euro supply, current x 230 = power usage
so if it draws 2A, it's using 460W

8 hrs a day is 8x460/1000 = 3.680 KW hrs per day
3.680 x 5 = 18.400 KW hrs per week.

I assume by "Enerysave mode" you mean you shut it down, therefore current use is neglegible.
IF you mean let it simply go to "idle mode" you need to repeat measurement but with it in this mode, and use a 16hr multiplier, add this to the above
Multiple by No of weeks you work in a year. ( I assume ou power it down for holidays at least)

Work out annual usage of power in KW hrs
multiple by cost of electricity per KW hr (remember if its a small value like 0.1 of your currency unit, to multiply by 0.1

This is approx running cost per year.

BTW if your local voltage is 110V the the initial multiplier for power is 110 not 230

Answer 2

$800/yr is pretty close to accurate - you can dramatically cut this cost just by substituting an LCD monitor instead of your CRT !! Also check all power settings in BIOS to see that any monitor standby timeouts are within your usage patterns.