Design of efficient cooling systems for hot and dry climate

Abstract

While weather conditions in relatively hot parts of the world (such as Ahmedabad in India) demands cooling solutions to maintain human comfort, it is important to understand the trade-offs between thermal comfort, cost, and the effect of any particular cooling technology on the environment. Conventional HVAC based cooling systems have relatively high operational costs along with high environmental impact. To address this problem, we have designed three low cost cooling systems for the proposed student dining halls at IIT Gandhinagar. This paper aims at developing thermal models to investigate the cooling potential of Direct and Indirect Active Evaporative Cooling, Earth- Fluid Heat Exchanger, and their combinations. Results indicate that any one cooling system will not be able to deliver air at desired conditions in extremely hot climate; hence, we recommend hybrid cooling systems. This paper provides simple design techniques for evaluating the performance of these hybrid systems. This will benefit architects and designers to build a design map, from which an optimized design can be chosen based on the constraints. All the proposed hybrid solutions have lower power consumption as compared to other feasible alternatives such as vapor compression based air conditioning systems.