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Separate sensible and latent cooling (SSLC) is a promising technology for enhancing the energy efficiency of space cooling systems. In this paper, we propose an SSLC configuration consisting of an indirect evaporative cooling (IEC) device and vapor compression cycle (VCC) for handling space sensible load, and a desiccant wheel for handling space latent load. The performance of the proposed configuration is investigated using physics-based or empirical models for each component. A year-round simulation study of the proposed SSLC system is performed for 12 different cities with diverse climatic conditions. This study considers electrical, thermal, or solar energy for desiccant wheel regeneration. Parameters governing the system performance such as the air flowrate ratio in the IEC and the DW, DW regeneration air temperature, and supply temperature are studied. The proposed SSLC configuration is superior to the conventional system in all cities. The enhancement of seasonal coefficient of performance (sCOP) ranges between 50 and 261 %, 67 and 387 %, and 60 and 2072 % with yearly electrical energy savings of 33 and 72 %, 40 and 79 %, and 38 and 95 % for electrical, thermal, and solar energy for regeneration of DW, respectively. [ABSTRACT FROM AUTHOR]

Developing countries, particularly those with high ambient temperatures (HAT), are experiencing a surge in air conditioner (AC) installations. Fixed-speed ACs, which rely on on–off control, are the most used. However, fixed-speed ACs lack humidity control and experience compressor cycling, leading to poor thermal comfort and increased energy consumption. Variable-speed compressor technology eliminates compressor cycling, which increases the effective coefficient of performance, especially at part-load conditions. This study compares the transient performance of variable-speed and fixed-speed AC units in Cairo, Egypt, as an example of a HAT environment. During a 2-month experimental investigation, the variable-speed unit provided 41% electrical energy savings while maintaining a comfortable environment. Analytical modeling using a machine learning model trained by the experimental measurements predicted annual energy savings of 473 kWh/year and an overall electrical energy savings percentage of 30.5%. The study also explored different scenarios for implementing variable-speed ACs in Egypt, a developing HAT country. With a 60% market penetration for variable-speed AC as the most probable scenario, the electrical energy savings up to the year 2032 add to 1.33 TWh, leading to 79.3 million USD in cost savings and 2.64 MMT of CO2 emissions reduction. [ABSTRACT FROM AUTHOR]