working out power consumption

[toxictoad]

hi there,

i've been wondering (haven't done anything other than that) about how much electricity i use and whether i could calculate things like, how much electicity i use in 4 hours, watching dvd's or 6 hours of sky and working on my laptop and then how much that costs me.

so, is it a case of checking each device for the amount of watts it uses, adding these up, multiplying the total by the number of hours they are on to give me the total number of watts used and then working out how much its costs based on how much a kilowatt per hour costs me?

if the devices don't specify how many watts they use what options are there in finding out?

thanks

 

[davy_owen_88]

if the devices don't specify how many watts they use what options are there in finding out?

Power = voltage x current.

A TV drawing 2A at 240V uses: 2A x 240V = 480W
If this TV is on for 4 hours: 0.48kW x 4 = 1.9kWh
If 1kWh costs 9p: 1.9kWh x 9 = 17.1p

If it doesn't tell you the current used then you can either:

buy a multimeter and measure it yourself
buy a power monitor (something like this.)
or if you are really desperate to know, then switch off every other appliance in your house. Get a stop watch and keep a close watch on the meter (might be a bit boring if its a very low power appliance. )

Davy

 

[toxictoad]

nice one Davy that explains it really well. much appreciated. can't see me sitting at the meter though

 

[sm1thson]

----edited-(i didnt see the link in the above post!)---------