Occupant engagement leads to substantial energy savings for plug loads

Abstract

Plug loads, defined as devices plugged into the wall outlet, comprise an average of 33% of a commercial building's total energy expenditure. Existing management technologies have overlooked the effects of building occupants on plug load usage. This study presents the results of a pilot deployment of a new plug load management technology by Keewi Inc. with active occupant engagement and automation technologies. 71 Electronic devices of 12 different equipment types belonging to 20 occupants working at offices of 3 recreation buildings at Stanford University were evaluated. For each device, a smart plug was used to 1) measure energy consumption (kWh) over time, and 2) turn off devices when not in use, leading to energy savings. The Keewi mobile application was used to enable participants to view their consumption, remotely control devices, set schedules, and engage in gamification strategies with points, rewards and competitions. The study included 27 days of baseline monitoring followed by 54 days of interventions, which resulted in savings of 21% in average daily consumption. The highest levels of savings were observed for speakers, shared printers and TVs. High occupant satisfaction was recorded with an average score of 7.1 (on a scale from 0–10) for increased knowledge of and engagement in energy saving activities due to the use of the technology. Occupant engagement is an effective strategy for plug load management that results in significant energy savings, high occupant satisfaction and the development of good energy stewards. Further studies are warranted to evaluate the effects in other settings.