Comparative Analysis of Vapor Compression and Hybrid Liquid Desiccant Dehumidification Systems

The objective of this study was to evaluate the energy savings of a commercially available hybrid liquid desiccant (HLD) cooling system relative to a conventional vapor compression system used for an existing school building where 100% outside air is used for ventilation. Psychrometric analysis and hour-by-hour simulations for three energy models were developed for three cities in the United States using available weather data assuming normal operation and typical building occupancy. Energy calculation software such as the Carrier Hourly Analysis Program (HAP 4.1) and Desicalc along with generated spreadsheets was used to compute the energy consumption for the models under study. Results of each model are summarized and comparisons are made. The annual energy savings employing the HLD system were found to reach 46% for Chicago, 37% for Gainesville and 32% for Miami. Simple cost analysis and associated payback periods were also performed.