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The present investigation aims to shed light on the efficiency of the irradiation-based advanced oxidation processes using controlled pulsed illumination (CPI) in a homogeneous process. A more in-depth emphasis has been applied considering the ultraviolet-light emitting diodes/persulfate (LED/S2O82−) system. Irradiation-driven processes can present unexpected behaviour under a pulsed irradiation compered to continuous irradiation. This behaviour can be explained by Parrando's paradox concept. The removal efficiency of organic dyes under a continuous illumination source was compared to the CPI system employing a pulsed UV-LED/S2O82− photoreactor to explore CPI performance. The efficiency of the pulsed UV-LED/PS method was investigated using three organic dyes as model pollutants and duty cycle and pulse period as parameters of the pulsed irradiation source. The duty cycle and pulse period have a crucial impact on the pulsed system efficiencies, which were studied in the values of 10 %, 25 %, 50 %, 75 %, 90 %, and 99 % for pulse periods from 1 ms (ms) to a few hundred ms in the current study. For all experiments, the electrical energy consumption (EEO) values were calculated, and the CPI values were compared to the continuous illumination values. According to the results, duty cycles and pulse periods of (10 %, 800 ms), (10 %, 1 ms), and (10 %, 800 ms), with the EEO amounts of 58.29, 120.65, and 29.62 kWh per order showed the best performance for the removal of organic dyes, respect to continuous irradiation and other CPI experiments in terms of saving energy. Besides, the game theory and the collision hypothesis were scrutinized to justify the achieved results.

Temperature is known to greatly affect the efficiency, security, and cycle life of lithium-ion battery (LiB) cells. LiB cells are delicate to changes in temperature by using a variety of nanofluids. This study uses a novel cooling system with a Re between 15 × 103 and 30 × 103 to lower the cells' temperature. Al2O3, CuO, SiO2, and ZnO with nanoparticles concentrations of 5% and nanoparticle diameters of 20 nm dispersed in a base liquid (water) are used to produce the effects. The findings demonstrate that as the Re rises, so does the Nusselt number. An innovative cooling system is designed and numerically tested to show how different kinds of nanofluids affect the increment in heat transmission and distribution of temperature in LiB cells. The temperature of LiB cells drops by flowing the water between the 52 batteries inside the cooling pack. For each spacing value, the Reynolds numbers are increased, which results in an increase in the average Nusselt numbers. According to the computational fluids dynamics results, the Nusselt number rises with increasing spacing. The results show that Re of 18000, 22000, 25000, 27500, and >30000 are needed for SiO2 nanofluids, Al2O3 nanofluids, ZnO nanofluids, CuO nanofluids, and pure water, respectively, to get battery pack temperature of 47, 44, 43, 42, and 42 °C for SiO2 nanofluids, Al2O3 nanofluids, ZnO nanofluids, CuO nanofluids, and pure water, respectively.

Lighting has evolved over recent decades from an engineering perspective, in which ensuring safety and performance both indoors and outdoors has become a key discipline, engaged in a wide range of areas and having a profound impact on our daily lives. In this paper, a case study of a modern public library building will be addressed, with the main purpose of discussing energy efficiency related to light. Three parallel routes will be demonstrated to improve energy efficiency. The first is the integration of solar systems (PV) and the replacement of artificial lighting systems. The second is a change of building materials, internally and externally, to nanomaterials, and the third is through including an innovative anidolic lighting system, designed and applied in order to enhance the amount of daylight inside the library in a controlled manner. The inclusion of a vertical lighting system allows the optimization of solar energy resources, preserving the library’s style in a simple way. The system includes a collector light system, compounded by a truncated and double compound parabolic collector (PCPC) to capture natural light from outside over a wide angular range (180°) without a tracking system, preserving the building design and saving on costs and maintenance. These parallel routes, based on solar energy and lighting, can make a positive impact with minimum changes in the Alexandria library, providing environmental improvement and protecting buildings and human health in order to achieve a more sustainable example of architecture.

In the office buildings, large energy is consumed due to poor thermal performance and low efficiencies of HVAC systems. A cooling load calculation is a basis for the design of building cooling systems. The current design methods are usually based on deterministic cooling loads, which are obtained by using design parameters. However, these parameters contain uncertainties, and they will be different from that used in the design calculation when the cooling system is put in use. The actual cooling load profile will deviate from that predicted in design. A modified bin method was used in this paper to optimize the energy efficiency ratio (EER). A design optimization method is proposed by considering uncertainties related to the cooling load calculation. Impacts caused by the uncertainties of seven factors are considered, including the outdoor weather conditions and internal heat sources. The cooling load distribution is analyzed. Comparison between the modified bin method and CLTD/SCL/CLF method is also conducted. With the distributions of their energy consumption, decision makers can select the optimal configuration based on quantified confidence. According to the economic benefits and energy efficiency ratio, using modified bin method will increase the overall energy efficiency ratio by 45.57%.

In this paper, a solar liquid desiccant air conditioning (SLDAC) system has been studied. The effect of changing evacuated tube collector area on the performance of the SLDAC system was fulfillment. This inquest was done over all a year in Borg Al-Arab city located in the Northern region of Egypt. Meteorological data, such as hourly average solar radiations and temperatures, were needed to achieve this research. The hourly cooling loads were determined by using Hourly Analysis Program (HAP) 4.7. These loads are wall, illumination, people, and equipment loads. Then, the hourly differences of different parameters such as amount of water absorbed in conditioner, amount of water desorbed in regenerator, hot water temperature and coefficient of the performance were calculated. In addition, the maximum solar thermal energy was determined to meet the regeneration demand according to the hourly average solar radiation data. For 220 m2 evacuated tube collector area, the maximum required heat energy is obtained as 38,286 kW h on December, while using solar energy, will save energy by 30.28% annual value.

This work discusses a waste heat recovery system (WHRS) applied to chimneys for heating water in residential buildings. A prototype illustrating the suggested system is implemented and tested. Different waste heat scenarios by varying the quantity of burned firewood (heat input) are experimented. The temperature at different parts of the WHRS and the gas flow rates of the exhaust pipes are measured. Measurements showed that the temperature of 95 L tank of water can be increased by 68 °C within one hour. Obtained results show that the convection and radiation exchanges at the bottom surface of the tank have a considerable impact on the total heat transfer rate of the water (as high as 70%).