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General discussion

Leaving Computer on -How much will it increase your energy

Nov 25, 2004 4:09PM PST

I ahve two computers that I leave on continuously. a 667 MHZ HP
and a 2300 MHZ emachine

I also have two printers and a scanner

Anyone know approx. how much energy in kilowatts this would be per month?

Discussion is locked

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Without measing...
Nov 25, 2004 10:50PM PST

Figure 100 Watts for under 1GHz machines, 200 for above 2GHz. Printers vary widely with my old Laserjet II sucking up 1,000 Watts when the heater element kicks in to today's laser that sips 4 or less Watts when just sitting there.

If the printers/scanners are newer, guesstimate 10 Watts each.

If you feel you don't want to guess, go to Radio Shack and buy the wall mount AC Watt Meter.

Bob

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Re: Leaving Computer on -How much will it increase your ener
Nov 25, 2004 11:06PM PST

Let's assume that your computer has a 250 watt power supply and your monitor runs at 100 watts. For a 24 hour period the energy consumption for just these two items is 8400 watt-hours or 8.4 KWhs. If these items are on for 30 days each month - you are using 252 KWattHours per month. If we assume a conservative estimate of $0.10 per KWh from your electric company, then you are spending $25 per month by leaving your computer running 24 hours each day.

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Just try to pull 250 Watts from a 250 Watt supply.
Nov 26, 2004 12:04AM PST
http://www6.tomshardware.com/howto/20021021/ noted that 6 out of 21 supplies were not able to deliver on their ratings.

As such, the rule of thumb for a reliable PC is to fit a power supply that your machine will draw about 1/2 the rated Watts.

I'd peg the 250 Watt supply to, on average consume about 100 Watts on a pre-built machine. And about 150 Watts if the user upgraded the machine.

Bob
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Look at it another way also
Nov 26, 2004 9:53AM PST

Most of the electricity used becomes heat. In the winter, this actually means reduces the amount of heat your furnace needs to produce. In the summer, if you have an air conditioner, it works a little harder.