If you attempt to save power in the house thoroughly, you can not ignore the standby power consumption of appliances. We made a device to measure the power consumption of appliances. Actually, to say the AC power meters measure the 100V AC current is flowing in the power cord over do it. In general, the voltage is measured casually, is difficult to measure the current. To cut off a part of the circuit current flow from a current meter must be connected to it.
AC Power Meter – [Link]