Khaled Khodary Esmaeil

The Kingdom of Saudi Arabia (KSA) is considered one of the countries with the highest consumption of electric energy per capita. Moreover, during the period of 2007–2017, the consumption rate increased from 6.9 MWh to 9.6 MWh. On the other hand, the share of residential electricity consumption in the KSA constitutes the biggest portion of the total electric consumption, which was about 48% in 2017. The objectives of this work were to analyze the exergy and assess the economic and environmental impacts of energy consumption in the residential sector of the Qassim region to determine potential areas for energy rationalization. The consumption patterns of 100 surveyed dwellings were analyzed to establish energy consumption indicators and conduct exergy analysis. The performances of different consuming domestic items were also examined, and energy efficiency measures are proposed. The average yearly consumption per dwelling was determined, and the total energy and exergy efficiencies are 145% and 11.38%, respectively. The average shares of lighting, domestic appliances, water heaters, and air conditioning from the total yearly energy consumption were determined.

Mixed convection heat transfer characteristics from heat source located symmetrically inside square enclosure and cooled by Al2O3/water-based nanofluid flow was experimentally investigated. The configuration was subjected to high levels of natural convection and low rates of nanofluid flow. The nanofluid thermophysical properties were characterized using the available correlations in the literatures except the viscosity which was measured and correlated in terms of the nanoparticles loading ratios. Comparative analysis indicated that the application of nanofluid could not guarantee heat transfer enhancement in configurations dominated by natural convection. Exception heat transfer enhancement was only found when very low nanoparticles loading ratio was applied. Instead, heat transfer degradation was found especially in the cases of highest nanoparticles loading ratios. Alternatively, heat transfer enhancement was observed when the forced convection effect was substantial at the highest nanofluid flow rate. The present conclusions were justified and correlated to the findings reported in the literature.

A benchmarking study was performed for two local water bottling factories in Saudi Arabia. The energy consumption values were compared with internationally reported values. For the local water factories a detailed energy audit was conducted to determine the energy consumption. The power consumption and power factor of each machine in the production process was measured using an energy analyzer. For one of the local energy audits, the heaviest consumption of power was by the injection molding machine, which consumed approximately 37% of the total power; the compressors accounted for 24%; while the chillers took 18% of total power. The power factors of different machines were in the range of 0.7 to 0.9. A benchmarking analysis showed an energy use index (EUI) of 0.41 MJ/liter and 0.29 MJ/liter for the two water bottling plants studied in this research, whereas international benchmarks reported are around 0.25 MJ/liter. Major energy conservation measures suggested were improvement of power factor, elimination of compressor leaks, implementation of variable-speed drives, and insulation of pipes running from the chillers.