Ask the Expert: How Can You Slay Office Phantom Loads?

Max Ma and Amanda Gasse, ERS

Question: Plug loads are one of the fastest growing sources of energy use in commercial buildings today. In offices, they account for 15%–20% of office electricity use. Due to COVID-19, commercial office building owners report that offices have not returned to normal occupancy levels. Yet tenants report that, while their electricity bills are significantly lower, they are still seeing significant plug loads from appliances that draw power from an electrical wall outlet, including computers, monitors, printers, copiers, vending machines, coffee machines, and many others. How can tenants and building owners successfully implement plug load controls in reduced occupancy commercial spaces and achieve real energy savings?

Answer: When plug loads draw power for an extended period in an idle mode, the idle power use is referred to as phantom power, since users are often unaware of this power consumption. Innovative solutions have been proposed and tested to reduce phantom power, with varying degrees of success. Most common solutions include smart power strips, wirelessly connected plug controls, and computer software. All plug load controls seek to shut off the controlled devices when active uses are not expected, such as during non-business hours in an office setting or after-store hours in a retail business. The following list highlights the spooky but practical solutions to slay your office’s phantom plug loads.

  1. Trick or Treat – User Education is Key: Educating daily office occupants who are closest to the plug load controls is critical! Without proper education, people may unintentionally remove the control devices or circumvent them. A good example is the case of a middle school, where wireless controls were installed to shut off office equipment after school hours without telling teachers and administrative staff. During an after-hours open house event, a frightened teacher noticed that printers, computers, and copiers were without power as if the school was haunted; she then discovered that bypassing the plug control restored power to the devices, and then this became a spine-chilling practice among staff members. The facility’s management team had never communicated the control’s capability to instantly restore power at the press of a button, resulting in hundreds of sophisticated controls sitting around as only ghostly outlet decorations.
  2. Be Wary of Device Interruptions that Cause Eerie Errors: As much as the plug load controls are intended for universal use, some devices are ghastlier than others when plugged into a control. IT professionals tend to be particularly spooked by scheduled computer shutdowns because they might interfere with remote updates and network maintenance. Modern smart devices – those with built-in computers and power-management capabilities – may be particularly susceptible to malfunctions after power interruption not initiated by the devices themselves.
  3. Account for Monstrous Schedules: A blanket schedule applied to each facility may also fail to account for the schedule requirements of each controlled device. While desk lamps and fans may turn back on within seconds, computers, printers, and copiers may require a few minutes, while refrigerated vending machines would require an hour or more to restore normal operation. As a consequence, vending machine controls are more likely to be bypassed by end users.