Demand Controlled Ventilation (DCV)
From Swikipedia
Introduction
Demand Controlled Ventilation is a ventilation-control strategy in which the concentration of CO2 (Carbon Dioxide) is the measured variable that is controlled to a set-point by modulating outdoor airflow. With this strategy, only human source contaminants are considered. In simple words, it is the ventilation provided in response to actual number of occupants and occupant activity.
Brief Description
DCV is mostly used in large assembly spaces such as gymnasiums, auditoriums, lecture halls, conference rooms, churches, and theaters, which are generally designed for large numbers of people with high outside air requirements. However, these spaces are frequently only partially occupied. It is expected that, in the future, most spaces with ventilation air capacities of at least 1,500 cubic feet per minute (CFM) and serving areas having an average occupant load factor of 20 or less will be designed with DCV features.
DCV is a ventilation control strategy that provides just the right amount of outside air that is needed by the occupants. Active control of the ventilation system can provide the opportunity to control indoor air quality which can lead to saving energy.
The components used in controlling outside air include an economizer or air make-up unit with modulating dampers; control sensors to communicate either directly with the economizer or with a central computer; carbon dioxide sensors; occupancy sensors and turnstile counters.
References:
http://whygreenbuildings.com/glossary.php
