Common sense suggests that when the switch is off on an electronic device, it is no longer using electricity. In this case, common sense is wrong, however.
Yesterday, Laura Sanchez at Forester Daily News offered a commentary on idle load consumption. Much of the piece is aimed at the residential sector. However, the situation is no different in non-residential settings: Electrons are electrons. Sanchez cites a 2015 study from the Natural Resources Defense Council that found that 23 percent of residential electricity is used by devices in “idle power” mode.
Sanchez does directly address non-residential spaces:
Idle energy consumption increases exponentially when we look at usage in larger spaces and commercial buildings. Office equipment such as photocopy machines, computers, and air conditioning units draw a tremendous amount of energy even in sleep mode or when powered off, creating massive idle plug loads for many commercial spaces.
The good news at the end of the commentary: People tend to be more judicious and are willing to confront “passive plug load” if it is called to their attention.
Smart management of devices that are off can be a big winner for energy managers. It seems likely that the 23 percent figure cited by Sanchez for residential settings would be the same or even greater for non-residential venues. It also seems that cutting into that figure to make significant gains would be fairly easy.
The greatest sources of savings almost certainly are consumer electronic and computing equipment. In this area, the line between consumer and business equipment is fuzzy, and many of the rules apply to both. The U.S. Environmental Protection Agency’s (EPA) Energy Star program suggests that a little foresight can go a long way:
Unplug electronics, or use a power strip and use the switch on the power strip to cut all power to the appliance, to avoid “vampire” loads. Many appliances continue to draw a small amount of power when they are switched off. These vampire loads occur in most appliances that use electricity, such as DVD players, TVs, stereos, computers, and kitchen appliances. Unplug battery chargers when the batteries are fully charged or the chargers are not in use.
The EPA suggests turning of computer monitors if the PC will be unused for more than 20 minutes and turning off the CPU as well if it will not be used for more than two hours. Software is available that can automate this process.
In September, Amgio Energy posted a blog outlining four tips on saving energy in office environments. One of these was to turn equipment off and programming computers to use sleep mode, which is less energy-intensive than idle. Surge protectors can be a useful tool for simultaneously disconnecting multiple devices from the power source. The piece suggests that somebody be responsible for making sure that the task is carried out on a daily basis.