Current Progress in District Cooling Infrastructures and Their Evolution to Integrated Vapor Absorption-Compression Refrigeration Systems

District cooling (DC) is an emerging approach to deal with heavy cooling demands since it offers substantial energy savings, up to 40%, compared to stand-alone cooling solutions. This paper focuses on DC plants and their implementation as infrastructures that include vapor absorption-compression refrigeration systems. Several DC plants in the Gulf Cooperation Council (GCC) region are functional: the anticipated penetration of DC in the GCC region will be 30% of the total cooling capacity by 2030. We address ongoing research challenges pertinent to DC plants to make the associated cooling infrastructure energy-efficient, environmentally and economically sustainable. Such challenges include the exploitation of the vapor absorption refrigeration (VAR) technology in DC plants, over the conventional vapor compression refrigeration (VCR) technology which is currently used in practice. The performance of the VAR-based DC plant can be improved by operating the VAR system with recently identified novel working fluids of refrigerants/absorbents that can be used to replace the conventional options. We propose the selection of working fluids considering both steady-state and dynamic performance. We discuss the performance improvement and cost benefits when an existing DC plant (currently driven by a VCR system) is operated with a stand-alone VCR or a stand-alone VAR or an integrated VCR and VAR system, either in parallel or in cascade configurations. Furthermore, the benefits of integrated VCR and VAR chiller plants operated with energy storage under demand variability are discussed.