Energy saving potential of liquid desiccant in evaporative-cooling-assisted 100% outdoor air system

The primary goal of this paper is to suggest integration of a liquid desiccant system into an evaporative-cooling-assisted 100% outdoor air system. Detailed energy simulation is performed for estimating the impact of the liquid desiccant system in indirect and direct evaporative cooler operations. The energy saving potential of the proposed system versus a conventional VAV (variable air volume) system is predicted via a series of energy simulations using TRNSYS 16 and a commercial equation solver program. Impact of water-side free cooling and solar thermal system on the operating energy saving of the liquid desiccant system is quantitatively evaluated. Simulation results showed that the proposed system consumes 51% less cooling energy compared to the conventional VAV system; primarily due to the water-side free cooling in maintaining the absorber temperature of the liquid desiccant system. The solar water heating system for regenerating the desiccant solution also contributes to the reduction in operating energy.

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