Performance comparison of temperature and humidity independent control air-conditioning system with conventional system

Abstract

The energy consumption of centralized air-conditioning systems represents a large percentage of total building energy consumption in commercial buildings. The temperature and humidity independent control system, regulating indoor temperature and humidity separately through different approaches, is a feasible improvement to conventional systems. This paper focuses on the performance discrepancies between the temperature and humidity independent control systems and the conventional systems. A typical office building in Guangzhou is chosen for case study and energy performances of three temperature and humidity independent control systems with different outdoor air handling processes are investigated. Compared to the conventional system, energy efficiency ratio for the entire air-conditioning season of temperature and humidity independent control system I using condensing dehumidification is about 10% higher if the dry fan coil unit is adopted; of temperature and humidity independent control system II with high-temperature chilled water for precooling is about 16% higher, and energy efficiency improvement of temperature and humidity independent control system III with heat pump driven liquid desiccant air handling processor is about 22%. For other three cities in China, the energy saving ratio of temperature and humidity independent control system I is about 10%, about 15%–17% of temperature and humidity independent control system II and 20%–23% of temperature and humidity independent control system III. Practical application: THIC air-conditioning system is supposed to be an effective approach for energy saving in buildings. Chosen a typical office building as an example, this paper gives the energy performance discrepancies between the conventional system and the THIC systems for researchers and designers. Annual energy consumptions for different air-conditioning systems are compared, and the energy saving ratios of THIC systems are obtained. The research will be helpful for designing and constructing an energy efficient central air-conditioning system for buildings. In these typical cities or cities with similar climate, THIC system III with the highest energy efficiency is recommended just from the perspective of energy saving.