Performance of grid-connected solar photovoltaic power plants in the Middle East and North Africa

A conceptual design Study of a solar electrical power system using PV array for a 5.3MW as nominal power required is presented. A Bird model has been used to estimate hourly, daily, monthly and yearly solar radiation amounts. f-f-chart is a design method was chosen to simulate the fraction of the solar energy required for the load given the PV array areas and climatic conditions. Four cities in the Middle East and North Africa representing different locations at southern Mediterranean region are selected Tripoli, Alexandria, Tunisia and Gaza city. Tripoli City has the best performance for 73% of nominal Power followed by Alexandria about 66% and then Gaza around 63%, Tunisia City has lowest solar fraction about 59% according to the Monthly and annual solar fraction Data

Article Effects of Viscous Dissipation on the Slip MHD Flow and Heat Transfer past a Permeable Surface with Convective Boundary Conditions

energie

Thermal comfort of an air-conditioned office through different windows-door opening arrangements.

This paper investigates the thermal comfort level of an office room through various windows-door opening arrangements in hot and humid climate. To determine the windows-door opening performance, 14 opening configurations have been considered and the combination of opening arrangements was carried out in an air-conditioned office at UPM, Malaysia. After conducting objective measurement for each condition, Predicted Mean Vote (PMV) and Predicted Percentage of Dissatisfied (PPD) were calculated. The concentrations of carbon dioxide (CO2) were also monitored. Subjective survey involved questions on the thermal environmental perception and indoor air quality for office occupants for this study. Objective data analysis showed that in most of conditions office had thermal conditions falling within the comfort zone of ASHRAE standard 55, and in all of conditions neutral temperatures are higher than ASHRAE standard requirements. Subjective results revealed that staff has higher thermal comfort level as compared to what PMV has predicted. Practical application: It is believed that the results in this paper will contribute to knowledge that international standards are not applicable in hot and humid climate. Fanger equations would give the results for European conditions, people in hot- humid climate have some cultural preferences that are different from the Europeans hence modifying these equations and standards for this climate are necessary. In terms of the use of climatic control to modify the indoor environment it is found that when the occupants have the freedom to modify the environment, and make necessary adjustment, they always use windows-door opening arrangements to compensate for the less comfortable thermal condition and increase air movement

Experiment study of water based photovoltaic-thermal (PV/T) collector

Solar radiation can be converted to the electrical energy and thermal energy by photovoltaic panel and solar collector. In this experiment, PV/T collector was designed, fabricated and tested its performance. The experiment conducted on PV/T collector with water flow at mass flow rate 0.012 kg/s to 0.0255 kg/s. The water flow with the stainless stell absorber help the PV/T collector in increasing the convection of thermal heat transfer. The power output increase with increase of radiation. The efficiency of PVT varies with different intensity of radiation which stated in this experiment for 750 W/m2 and 900 W/m2. The analysis of energy and exergy are excuted and results show energy output for water based PV/T collector are 346 W for solar radiation 700 W/m2 and 457 W for solar radiation 900 W/m2.  Meanwhile the total exergy output compared to the PV panel without stainless stell absorber, which the exergy increased by 22.48% for 700 W/m2 and 20.87% for 900 W/m2

Review of water-nanofluid based photovoltaic/thermal (PV/T) systems

Solar energy is secure, clean, and available on earth throughout the year. The PV/T system is a device designed to receive solar energy and convert it into electric/thermal energy. Nanofluid is a new generation of heat transfer fluid with promising higher thermal conductivity and improve heat transfer rate compared with conventional fluids. In this review, the recent studies of PV/T using nanofluid is discussed regarding basic concept and theory PV/T, thermal conductivity of nanofluid and experimentally and theoretically study the perfromance of PV/T using nanofluid. A review of the literature shows that many studies have evaluated the potential of nanofluid as heat transfer fluid and optical filter in the PV/T system. The preparations of nanofluid play an essential key for high stability and homogenous nanofluid for a long period. The thermal conductivity of nanofluid is depending on the size of nanoparticles, concentration and preparation of nanofluids

On the Performance of Hybrid PV/Unitized Regenerative Fuel Cell System in the Tropics

Solar hydrogen system is a unique power system that can meet the power requirements for future energy demands. Such a system uses the hydrogen as the energy carrier, which produces energy through the electrolyzer with assistance of the power from the PV during the sunny hours, and then uses stored hydrogen to produce energy through the fuel cell after sunset or on cloudy days. The current study has used premanufactured unitized regenerative fuel cells in which the electrolyzer and the fuel cell function within one cell at different modes. The system components were modeled and the one-day real operational and simulated data has been presented and compared. The measured results showed the ability of the system to meet the proposed load, and the total efficiency was about 4.5%

Quran as Inspiration for Implementation of Pico Hydro System

ABSTRACT Islam urges Muslims to protect and preserve the environment and not to ruin the nature. This is mentions in the Holy Quran through several verses in many chapters. Therefore, when we talk about renewable energy such as Pico hydro, the green energy or technology suits the teaching of Islam. Allah the All Knowing emphasizes in the Quran the importance of knowledge. Similarly, in many Hadiths the Prophet Muhammad insisted for the Muslims to seek knowledge. Through the Holy Quran, Allah mentions all sort of knowledge such as science and technologies, commerce and economy, health and medicine, laws, history and philosophy, and astronomy. This paper discusses about the basic theories related to Pico hydro power engineering that is proved and mentioned in the Holy Quran. From the observation, it is found that many encounters from research works in the field of hydropower have been approved and produced; but Quran still the best as a reference. Thus, the Quran is clearly preserved by Allah S.W.T. and will be always becomes the main source of knowledge and guidance, as well as the inspiration to all humankind in every aspect of their life, including knowledge such as science and technology: the utilization of the water power for Pico hydro system

Effects of urban canyons and thermal comfort in the Persian Gulf region

Accessibility to thermal comfort spaces for citizens and urban outdoor activities could be one of the main goals of urban designers. The objective of this paper is to conduct a comparative study on two different urban fabrics, using thermal comfort and Computational Fluid Dynamics (CFD) methods. Results relate the effects of urban canyon's orientation on variation of the microclimate factors and consequently, on the thermal comfort situation in the hottest period of the year. The results indicate that traditional urban fabric is more thermally comfortable than the new residential urban fabric. According to the field measurements, thermal comfort calculation, and wind simulations, the canyons with North-South direction represent a better orientation for air circulation benefiting from sea breezes as compared to other canyon orientations. The result will throw light for the urban designers and policy makers of hot and humid climate in the Middle East

Mathematical modeling and validation of solar-induced ventilation system for vehicle cabin cooling in hot parking conditions

Exposure to direct sunlight raises interior temperatures in vehicle cabins, risking heat-related illnesses. Solar passive techniques mitigate this issue, especially during hot parking conditions. However, a comprehensive mathematical model encompassing both solar chimney and vehicle cabin is lacking. This study develops a novel mathematical model to predict temperature distribution and airflow rate, enhancing system performance evaluation. The system comprises a solar air collector with an adjustable arm mounted on the vehicle's roof. The model was validated theoretically and experimentally. The experimental work is conducted with the physical model with an air gap of 0.1 m, 0.77 m width, and a 1.12 m collector length underoutdoor conditions. Results indicated a gradual increase in temperatures of the glass cover, air in the collector channel, absorber, and mass airflow rate with solar radiation intensity, significantly influencing system performance. The high value of R2 and the consistency of the model's results with theoretical and experimental outcomes justified the validity and accuracy of the proposed model, exhibiting a deviation percentage of less than 10%. The developed model can be utilized to study influential parameters for optimizing the proposed strategy's performance and components, yielding comparable results to experimental data. Additionally, it provides researchers and car makers with a broader perspective and a range of options for further improvement in weight, size, cost, and aerodynamic of the vehicl

Review of materials for adsorption refrigeration technology

Purpose: During the last 20 years, interest in the closed adsorption heat pump and refrigeration systems has increased steadily. In this paper, consideration is given to aspects of adsorption refrigeration in terms of existing materials used in adsorption refrigeration, heat transfer characteristics of materials, and cost of materials and manufacturing. Design/methodology/approach: The paper is a general review of adsorption refrigeration technology. Findings: In recent years several papers have been published in this area and many aspects of the system have been addressed. Much effort has been devoted to enhance materials properties. Originality/value: The paper provides information of value to those involved with heat pump and refrigeration systems technology