Computer power consumption

Down and Dirty Computer Power Consumption.

Most home computers have a power supply in the 200-400 range. Generally, power supplies are over-rated for any particular computer as running it at maximum would quickly burn out the power supply (although we've seen many that were just too close for comfort!)

Because items such as floppy drives and CD drives are used only on occasion and have a significant amp draw, we are using 50% the power supply rating as a basis for the computer. The following assumes the computer is on and active 24x7 and the monitor is on but in the power savings mode half the time.

So, assuming we did our math correctly...

	Computer	Monitor
Rating in watts
Hours per day the item is on and active.
Hours per Year
Kilowatts per Year
Local cost per Kilowatt $
Cost per Year (rounded to nearest buck)
Cost per Month (rounded to nearest buck)

Notes:

100 watts (used here) is high for modern 17 inch monitors.
Flat panel (LCD) monitors consume less than half a same sized CRT, i.e., a 17 inch flat panel draws less than 40 watts when on.
When in standby, CRT monitors drop their consumption to around 7 watts, flat panels less than 5 watts