Examples of estimating occupancy
* Timed schedules * Motion sensors (various technologies including: Audible sound, inaudible sound, infrared) * Gas detection () In a survey on Norwegian schools, using CO2 sensors for DCV was found to reduce energy consumption by 62% when compared with a constant air volume (CAV) ventilation system. * Positive control gates * Ticket sales * Security equipment data share (including people counting video software) * Inference from other system sensors/equipment, like smart metersCarbon dioxide sensing
Carbon dioxide sensors monitor carbon dioxide levels in a space by strategic placement. The placement of the sensors should be able to provide an accurate representation of the space, usually placed in a return duct or on the wall. As the sensor reads the increasing amount of carbon dioxide levels in a space, the ventilation increases to dilute the levels. When the space is unoccupied, the sensor reads normal levels, and continues to supply the unoccupying rate for airflow. The amount of air supplied is determined by the building owner standards, along with the designer and ASHRAE Standard 62.1.References
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