Will my electric bill decrease when I unplug appliances not in use? This is the question of many people perhaps. Let us find out if there is really a savings from unplugging devices not in use. Many of us rely only in the remote control to put our appliances in sleep mode or standby mode but not totally cutting the power entering the appliances. At standby mode, appliances still consume power due to its fixed biases. One of the major contributors of this fixed loss is the appliance power supply. Based on experience as a power supply design engineer, a poorly designed power supply has higher no load or standby power dissipation. A high end power supply on the other hand has very small standby or no load power. However, the built-in power supply inside appliances has higher no load power usually. The no load or standby power may vary from 0.5W to 10W. The 0.5W-1W is attainable for high end off the shelf power supply with a power range from below 100W to 400W. However for internal power supply of each appliance, the no load power may reach as high as 10W. You may be thinking that only the LED indicator is consuming power at no load or standby condition, but the internal bias as well. The no load power may increase higher than 10W for high power appliances. Apart from power supply, there are also another contributing factors. Below table is the study result of common appliances standby power. The survey is conducted between 1998-1999 so other appliances such as computer is not yet included here.
Considering you have 2 television sets, a home theater, a stereo system and a desktop computer. TVs has its internal AC-DC power supply because the internal circuit is DC powered. Home theater, stereo system and desktop computer are having the same. Aside from the power supply standby consumption, other fixed bias too is contributing.
Let us consider the average data, for TVs the average standby power is 7.3 Watts. For home theater we will consider 14.4 Watts. For the stereo system consider 7.2 Watts and 5 Watts for desk top computer.
The total standby power is
Assuming you use these appliances for 8 hours a day and setting to standby mode for 16 hours per day; the total wasted energy daily is
For a year, the total wasted energy will be
Considering the cost per kWHr is 0.15$US, the yearly wasted money will be
Is this convinced you to unplug your appliances? May be not if you have only few appliances. However, you have to take note that the yearly wasted money might double when appliances get older. So the 35.5968$US will become 71.1936$US and a monthly savings of 5.9328$US. And now, back to the question Will My Electric Bill Decrease when I Unplug Appliances not in use?…You should have an answer by yourself now.
For personal or house hold consumption wherein there are few appliances only, the savings is not that big. However for big establishments having high power appliances the savings is big.