how many kw/hr does my computer use?

[bsspewer]

i'm looking for reasons on why my power bill is what it is. One thing i've always wanted to know, is how much does my computer cost me a day to run? i leave it on all day and shut it off at night. So how much is that costing me? I'd like to find out if there is something i can plug in between my computer and the wall socket that can give me some kind of readout, that i can convert to how many kilowatts per hour i'm using, to find the cost of power my computer needs.

they sell anything like this at radioshack?

[I.M.O.G.]

http://forum.oc-forums.com/vb/showthread.php?s=&action=showpost&postid=926053

[Matthias99]

That's the only time I've ever seen voltage referred to with an "E" instead of a "V", and he didn't even mention the word "current". :p

He also briefly mentions power factor, but that doesn't come into play the way he's computing his usage (by calculating wattage W = IV). A crappy power supply will make the computer pull more amps for the same workload (that is, the input wattage will be higher for the same output wattage of the power supply), but that equation won't change. You'd have to take it into account if you were totalling up the equipment in your computer and trying to calculate how many watts it requires that way.

In short, it shouldn't cost all that much to run a computer 24/7, as long as you have the monitor off most of the time!

And yes, you should be able to buy a plug-in watt meter from Radioshack which will simply tell you how many watts it's pulling at any given time. Then just multiply it out to get how many kilowatt-hours it'll use in a month.

[bsspewer]

yea..thanks alot guys. That helps. Unfortunately i do leave my moniter on all day along w/ the computer, and turn it all off at night.

At least i know how much mine and my roommate's computers cost us a month to use. On to find what other things it could be that's causing our power bill to go up. Considering even if we don't use the AC, it'll still be higher.

[JigPu]

Have windows turn your monitor to standby mode after 5 minutes or so, and your power drain should drop a bit. I don't have any KWh figures, but when my dad was trying to see where he could save electricity, we found that my old 466MHz celeron used about as much electricity as a 60W lightbulb under load (monitor off). I wouldn't imagine that a modern computer would use much more than 100 or mabey 200W though.

JigPu

[I.M.O.G.]

Originally posted by Matthias99
That's the only time I've ever seen voltage referred to with an "E" instead of a "V", and he didn't even mention the word "current". :p

I could be mistaken, but I believe thats a foreign thing maybe?

[Matthias99]

Maybe, but I'm pretty sure any electrical engineer in the world would write Ohm's Law as V=IR. The symbols and letters for these things are standardized so that you won't get confusion.

Current is measured in Amperes (A). "I" is used in electrical engineering, probably because of some French guy. That's usually why these things happen. :)

Charge is measured in coulombs (C), and potential difference is measured in Volts (V).

Resistance is measured in Ohms (Greek letter Omega), but as Omega is difficult to type, R is often used.

Power is measured in many units, but for electrical circuits they usually use Watts (W), which is another name for Volt-Amperes (W = V*A).

http://physics.nist.gov/cuu/Units/units.html

[9mmCensor]

Originally posted by Matthias99
he didn't even mention the word "current". :p
]
second para BOLD letters


To start off. We need to understand some formulas and definitions. One of the most basic formulas used in electricity is P = IE where P is Power, I is Ioda or Current, and E is Electromotive Force.

[ajrettke]

E is used more by physicists....who hate EE's use if j for (-1)^.5 instead of i (which is current). There are devices that monitor current, but for current that large they wouldn't be cheap.
Also the reason pf isn't mention is because it's almost a non issue for most residential households (in fact I believe power companies go off soley KW and not KVA for residential areas). the PF is probably .99 or very close, which is not a big loss to power company.
Now when large buisness start using induction motors and get PF's of .7, the power company starts really charging em hard, and they usualy install capacitor banks to get the pf down.