Health and energy assessment of a demand controlled mechanical extraction ventilation system

Abstract

Today, the assessment of residential demand controlled ventilation systems only considers the perceived indoor air quality in terms of comfort, with CO2 and humidity as the main parameters to investigate. However, the ventilation system and its controls also have an impact on the health aspect of Indoor Air Quality (IAQ) due to the higher exposure to unhealthy pollutants (Volatile Organic Compounds (VOCs), fine dust particles, e.g. PM2.5). In this paper, two demand controlled mechanical extraction ventilation systems (DCV) and a continuous mechanical extraction ventilation system (MEV) of a typical Belgian apartment are modelled using Modelica. This allows to simulate the combined effect and interaction of temperature, airflow and IAQ. The model includes sources of CO2 humidity, VOCs and PM2.5 to the indoor air. The combined approach using Modelica allows to do an in-depth analysis of the indoor air quality. A two-stage assessment method is performed, resulting in an overall performance (in terms of IAQ and energy use) of a DCV system in relation to the performance of the MEV reference system.