Investigation on the use of desiccant In dedicated outdoor air systems

Abstract

This report presents an investigation on the thermal comfort level and the rate of energy consumption of the 3 systems, namely conventional chilled water cooling system, active chilled beam systems with electrical heater and active chilled beam with solar collector. This project is based on the simulation modeling of the 3 systems and their performance data generated by the TRNSYS software were used to make comparison. Performance data of 3 systems showed that they are able to meet the requirements of Thermal Comfort. In addition, active chilled beam system with electrical heater and solar collector can yield approximately 10% and 24% of the power savings over the conventional cooling system. With the additional desiccant dehumidification system, the initial cost of active chilled beam will definitely increase. However, as the desiccant dehumidification system is able to reduce the chiller cooling capacity by removing the moisture load from ventilation air which results in savings enough to offset for the cost of the desiccant system and further reducing the operating cost in the long run.

Since Singapore is typically dominated by high rise buildings, it is important that these buildings are energy efficient in ways of using the natural resource efficiently and wisely. A research into the areas of active chilled beam with solar collector should be conducted because it is the most energy efficient system among the 3 systems which has been proven in this report.