How to use a plug-in power meter?

weyland-yutani

Plug-In Power and Energy Monitor: Amazon.co.uk: Electronics

just bought one of these but have no idea how to actually find out how much money a particular appliance is costing. the instruction just detail functions but not what to with the readings. any one have any ideas?

thanks.

paulktreg

You first need to find out how much your electricity supplier charges for one kilowatt/hour of electricity, usually shortened to kWh. This can vary throughout the day.

I am as I type paying approximately 11p per kWh according to my smart meter but this does vary and I've seen as much as 20p per kWh during peak times. Take an average of 15p per kWh (1000W for one hour) for this example.

Take the watt reading for your particular appliance. A PC for example may be 300W. That would cost (300/1000)*15=4.5p/hour.

Does that make sense?