Design of Solar Energy Based Air-Conditioning System for Climatic Conditions of Pakistan /

Abstract

Cotemporary Energy issues, like depletion of energy resources, rising energy costs and the related environmental issues demand exploration of renewable energy technologies. Solar powered desiccant based air-conditioning systems using solar thermal collector or solar photovoltaic/thermal collector is an emerging renewable energy technology. These systems are very attractive alternative to conventional refrigeration systems for reduction in peak load demand of electricity. This research reveals the feasibility and optimization analysis of a solar desiccant cooling system by using TRNSYS simulation software for Typical Meteorological Year data of Islamabad, Pakistan. TRNSYS is a tool used for modeling of renewable energy systems. A simulation model that contains solar PV/T collector, storage tank, direct evaporative cooler, vapor compression chiller and the building is developed. The results depict that desiccant system of rated capacity 2.5TR is designed for climatic conditions of Islamabad. The study also reveals that to increase the reliability of operation, an optimized system containing 15 m2 area of flat plat PV/T collector sloped at 15o is required. Hot water storage tank of 0.5 m3 and auxiliary heater having set point temperature of 60 0C is essential to provide effective cooling to the building. The economic analysis shows that the system has simple and equity payback period of 7.4 and 6.4 yrs. respectively. It could be reduced by using the same system for water and space heating by adding the few controllers and devices for the winter season.