No, not the Beck album. Here I refer to devices that draw power even when not in active use.
Over the past few years, I have read a number of studies that indicate between 5% and 10% of household energy is consumed by these devices. Look around your room and the vampiers are everywhere! For example, your DVD player, cell phone charger, and microwave are always on, but not at full power. Some of these devices provide services when they are in this low-power mode. A microwave, for example, might have a digital clock, where as your DVD player and TV are in a standby mode allowing you to turn them on with a remote control. Other devices like cell phone or computer chargers when plugged in provide no services to the user unless it is activley charging.
I recently purchased a Kill a watt(TM) power meter to see how much power in my household was being consumed by the “vampires”. Our entertainment center consists of a 32″ LCD TV, DVD player, VCR, a DVR, a cable modem, and a wireless router. Together these devices use about 30watts of power when in stand by mode. This doesn’t seem too bad, but it is equivalent to having a standard 60W bulb on for 12 hrs a day. The sad thing is that we only use them for about 2-3hrs a day. These devices are all on a power strip which we try to turn off when not in use, but we sometimes forget. So we use a simple timer to switch them off at night and during the day.
My electric toothbrush and razor each consume about 3W because they are continually in charge mode. I now routinely unplug the razor until it needs a charge. Office devices like a desk top computer use about 5W when in standby mode and about 90W at full power. My laptop charger used about 20W to charge and <1W when not charging. An idle external hard drive consumed an additional 2W as did a label maker. These devices are now unplugged when not in use. Any device that has a brick like power converter (aka wall warts) uses power when plugged in. You can tell by feeling it – is it warm? That is electricity being disipated as heat.
I was pleasantly surprised to see that our cell phone chargers and camera charger used less power than was detectable by the power meter (<1W). I plugged in 3 cell phone chargers and a camera charger and combined the used less than a Watt. Perhaps this is a reflection of the International Energy Agency’s One Watt Initiative. Other devices like toasters, blenders, coffee makers, etc. used no power even when plugged in. This would of course change if they had timers or clocks of some sort.
Our entire household inventory of devices that provided no useful function when off, totaled at around 50W and most of this was for the entertainment center. We found a power strip and timer to be an easy way to manage these devices and others we just unplug unless needed. Some devices like night lights, our toothbrush, microwave, and radio we decided to just leave plugged in mainly due to the inconvenience unplugging them between frequent uses. Still we managed to beat back the vampires by about 75%.
For more informion, Alan Meire of the Lawrence Berkeley National Laboratory maintains an excellent website on this issue. There you will find a comprehensive list of the power consumption of nearly every appliance in existence.