I remember there was a time when the electric bill in my pad went over Php14k, almost double the usual amount I pay on regular months. We use a lot of electrical devices, including 2 desktop PCs and a number of laptops so I thought of doing a simple experiment.
For about a month, I would not touch one of the desktop PCs in my room and use a laptop instead (even for the more task-intensive and gaming routines) and see how much would that affect the total power consumption.
My computation was this — a typical laptop would max out at 90watts in power consumption while a mid-range desktop PC (with a discrete GPU) would use up to around 500watts. If you include a large monitor, that’s another 50 watts.
Assuming the computer is on and running for about 12 hours a day, that’s 550watts x 12hours/day x 30days/month to give you a total of 198kW.
For a laptop, that’s just 90watts x 12hours/day x 30days/month for a total of 32kW.
The difference of 166kW amounts to about Php2,158 for the whole month (electricity rate pegged at Php13/KWhr). In a year, you can actually save enough money to buy another laptop. If you use a netbook instead of a full-sized laptop, that’s around 40watts/hour of power consumption and could drop your bill by another Php234 per month.
If you also have aircon in your room, the heat dissipation coming from the PC could add to the power consumed by the aircon to cool the room to the desired temperature (though there’s no way for me to figure that one out).