**9. Concluding remarks**

The HVAC load can be reduced significantly using renewable energy based desiccant cooling systems due to lower requirement of input power for these systems and effective utilization of alternative resources of energy. These systems prove to be an effective alternative to conventional cooling systems which are energy inefficient and as well as minimize greenhouse gases emissions. In this chapter, a comparative study has been presented among two different configurations of a solar desiccant cooling system operating in the hot and humid climatic condition. The two desiccant cooling cycles namely, ventilation and recirculation are solved theoretically to analyze and compare the system performance. The results showed that COP of the system operating on ventilation mode is higher than the system operating on recirculation mode. Therefore, based on the condition of ambient air, solar desiccant cooling system under the ventilation mode is more suitable than the recirculation mode. This paper also analyzes monthly performance of the system operating under both modes. Furthermore, the analysis of the supply air condition shows that the system is able to provide human thermal comfort in humid climates and it can be an alternative for the conventional air conditioning system. The economic evaluation shows that the larger systems have lower cost as compared to smaller units.

Although progress has been made in the development of this alternative cooling technology but a number of steps still needs to be taken in order to make this technology more market accessible. More research should be conducted on other innovative desiccant cooling systems integration, taking into consideration the associated investment costs. The development in liquid desiccant technology is in progress and it has attaining stability in the market. Furthermore, in order to access this technology in comparison to conventional cooling systems, hidden costs of fossil fuels should be accounted. Understanding the hidden impacts of fossil fuels is critical for evaluating the true cost of conventional power generation systems and has to be communicated to the community.
