Annual Average Efficiency Research Articles

Performance assessment of a 30.26 kW grid-connected photovoltaic plant in Egypt

Abstract This paper presents an experimental analysis and performance evaluation of a grid-connected photovoltaic plant installed on the rooftop of the Electronics Research Institute in Cairo, Egypt. Cairo is classified as a hot-desert climate region according to the standard Koppen-Geiger climate classification system. Over a year, we monitored real-time data to assess key system performance metrics, such as energy yield, efficiencies, performance ratio, capacity factor, and losses. Based on the obtained experimental results, the highest final yield of 5.2498 hr/day was observed in the summer, whereas the lowest yield of 3.439 hr/day occurred in the winter months. The photovoltaic plant had an average annual system efficiency of 15.8%, while the photovoltaic and inverter had mean yearly efficiencies of 17.1% and 97.2%, respectively. The average annual performance ratio is 83.03%, and the capacity factor is 18.72%. The monthly total loss exhibited a linear rise alongside increasing ambient temperature and solar irradiance. The ambient temperature affected the system efficiency, photovoltaic efficiency, and performance ratio. The findings can help strengthen forecasts of future large-scale photovoltaic plants in hot desert climates. Moreover, they can guide the design, optimization, operation, and maintenance of new grid-connected photovoltaic systems.

Performance investigation of a building-integrated collector based on spectrum splitting technology

Based on solar spectrum splitting technology, a novel concentrating photovoltaic/thermal (CPV/T) solar collector is proposed, which primarily composed of six Fresnel collector units with separate photovoltaic and photothermal modules. The compact overall structure is optimally designed that can be effectively integrated with ordinary buildings while supply both electrical and thermal energy. The proposed collector achieves the maximum annual average optical efficiency when installed north–south axially with a tilt angle approximately equal to the installation latitude, as a 64.97 % in Nanjing (32°N). Simulation analysis shows that the main influencing factors of the system performance are direct solar irradiance, working medium mass flow, and optical efficiency, the theoretical outlet working medium temperature can reach 150 °C while the photovoltaic and photothermal efficiencies are 12.37 % and 39.74 % when the normalized temperature difference T* is 0.06. Further, to verify the theoretical/simulation analysis results, the outdoor experimental tests are conducted and show that the optimal inlet working medium mass flow is 10.8 kg/h, while the efficiencies are 5.99 % and 27.59 %, respectively, that is, the proposed system comprehensive thermal efficiency can reach 43.35 %. The comparative analysis of theoretical research and experimental tests shows that the proposed system has rationality and practical value, which can provide guidance for practical engineering.

Spatio-temporal differentiation characteristics of coal mine safety levels in China based on spatial spillover effects

In order to solve the problem of "potpourri" of safety risk prevention and control measures, which is caused by the unclear mechanism of the spatial effect of coal mine safety level heterogeneity and its influencing factors. This paper discriminates the dominant factors of spatio-temporal heterogeneity of coal mine safety production level in China and their spatial effect types by means of GeoDetector and the Spatial Dubin Model (SDM), specifies the categories and degrees of acts on local and surrounding areas by changes in indicators, and provides further visualization of the detection outcomes with the assistance of the Neo4j graph database, and the findings indicate that:(1) All 15 indicators selected in the study have a certain influence on the generation of spatial heterogeneity in China's coal mine safety production level, and all of them show an enhancement relationship after the interaction of indicators. Especially, the combination of excavated environment and other indicators basically has a non-linear enhancement relationship. (2) In terms of spatial effects, the influence of the 5 effects on the spatio-temporal heterogeneity of coal mine safety level is, in descending order, industrial development effect > capital allocation effect > production environment effect > government supervision effect > enterprise management effect, which indicates that macroeconomic and market conditions have a much stronger influence on the generation of spatio-temporal heterogeneity in coal mine production safety status. (3) From the single indicator perspective, the average annual temperature, average annual wind speed, coal consumption and monitoring efficiency primarily affect the dependent variable through direct effects; GDP per capita, average labor compensation as well as railroad operating mileage have positive spatial spillover on the changes of coal mine safety production level in surrounding areas; the evaluation of the spatial effect for average labor compensation exhibits a positive indirect effect with low influence; for the two indicators of production efficiency and ex-factory price, not only do they have negative effects on the local coal mine safety level, but also have significant spillover effects on surrounding areas.

From resources to capital: Investigating the efficiency of forest ecosystem products value realization in China

Forest resources provide a good ecological environment for human beings and offer economic well-being and benefits. Value realization of ecosystem products reflects the process from resources to capital. This study investigates the two-stage value realization efficiency of China's forest ecosystem products from 2011 to 2021. A parallel nested network Data Envelopment Analysis model is applied to assess product supply and value transformation stages. In addition, the evolution of the spatial pattern is depicted by a multilayer Standard Deviational Ellipse. The results reveal that (1) the overall value realization trend of China's forest ecosystem products shows a fluctuating growth trend, with an average annual efficiency value of 0.86. (2) The efficiency level of the value transformation stage is lower than that of the product supply stage. (3) Regional disparities persist. The efficiency values in East China and South China are higher than that in other regions. (4) The value realization capacity of China's forest ecosystem products may be closely related to national development strategies and policy orientations.

Occurrence, distribution, and fate evaluation of endocrine disrupting compounds in three wastewater treatment plants with different treatment technologies in Türkiye

Nowadays, two of the endocrine disrupting compounds (EDCs) in the group of alkylphenols (APs), nonylphenol (4-NP) and octylphenol (4-t-OP), have attracted great scientific and regulatory attention mainly due to concerns about their aquatic toxicity and endocrine disrupting activity. This paper investigated the occurrence, distribution behavior, fate, and removal of 4-NP and 4-t-OP in liquid and solid phases of three full-scale wastewater treatment plants (WWTPs) with different treatment technologies comparatively. In this context, (i) advanced biological WWTP, (ii) wastewater stabilization pond (WSP), and (iii) constructed wetland (CW) were utilized. In all three investigated WWTPs, the concentrations of 4-NP (219.9–19,354.4 ng/L) in raw wastewater were higher than those of 4-t-OP (13.9–2822.4 ng/L). Within the scope of annual average removal efficiencies, 4-NP was treated highly in advanced biological WWTP (93.5 %), while it was almost not treated in WSP (3.1 %) and treated with negative removal (<0 %) in CW. While 4-t-OP was treated at a similar removal rate (93.5 %) to 4-NP in advanced biological WWTP, it was treated moderately in WSP (52.5 %) and very poorly in CW (12.4 %). It has been determined that the most important removal mechanism of both 4-NP and 4-t-OP in WWTPs is biodegradation, followed by sorption onto sewage sludge. According to the mass balance performed in advanced biological WWTP, the biodegradation rates for 4-NP and 4-t-OP were found to be 70.4 % and 86.6 %, respectively, while the sorption onto sewage sludge were determined to be 23.3 % and 6.8 %. One of the critical findings obtained within the scope of the study is that while the concentrations of both metabolites, especially 4-NP, in wastewater and sewage sludge, decreased considerably under aerobic conditions, on the contrary, their concentrations increased significantly under anaerobic conditions. Both compounds were detected at higher concentrations in primary sludge compared to secondary sludge in advanced biological WWTP, while in WSP, they were determined at higher concentrations in anaerobic stabilization pond sludge compared to facultative stabilization pond sludge. Besides, it was also determined that the sorption behavior of these alkylphenols is much more dominant than desorption.

Mathematical modelling and optimizing design of heliostat field

The heliostat field is a form of solar thermal power plant, The heliostat field is a crucial component of solar thermal power plants and establishing a heliostat field is of great significance for reducing carbon emissions. and is of great significance in reducing carbon emissions This paper focuses on the mathematical modeling and optimization design problem of the heliostat field. For three different design scenarios, firstly, based on the data provided by the China Undergraduate Mathematical Contest in Modeling 2023, a geometric optical efficiency model is proposed to determine the annual average optical efficiency and output thermal power under specific heliostat field design parameters. Secondly, aiming at the optimal design parameters of the solar furnace field under the condition of rated annual average output thermal power is 60 MW\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ ext{MW}$$\\end{document}, Particle Swarm Optimization (PSO) combing with efficiency model is utilized to determine the optimal design parameters of the heliostat field. Finally, this paper uses Quasi-Monte Carlo ray tracing (QMCRT) model to perform simulations, exploring how to obtain the optimal design parameters of the heliostat field with the goals of maximizing the output thermal power and ensuring high efficiency. Furthermore, the influence of normal disturbances on the annual average annual average thermal output power is investigated.

Occurrence, Fate, and Removal of Selected Antibiotics in Advanced Biological Urban Wastewater Treatment Plant

Wastewater treatment plants (WWTPs) are considered as one of the most important point sources for releasing antibiotics into the natural environment. In this study, the occurrence, fate, and removal of three antibiotics, ciprofloxacin (CIP), sulfamethoxazole (SMX), and azithromycin (AZI), belong to quinolone, sulfonamide, and macrolide groups, respectively were investigated seasonally in a large-scale urban WWTP. While the occurrence concentrations of the investigated antibiotics in raw wastewater were found between about 0.26 and 0.73 μg/L in the summer season, it was determined in the range of approximately 0.41 and 4.6 μg/L in the winter season. Although the removal efficiencies obtained for antibiotics in the pre-treatment stage of the studied advanced biological WWTP were not very high, the most treated compound in the pre-treatment stage was determined as CIP (up to 23.8%). Total removal efficiencies of the investigated antibiotics in the WWTP varied mainly based on the biological treatment stage of the WWTP. At the same time, removal efficiencies of the antibiotics obtained in the biological treatment also changed considerably depending on the seasons. Among all the investigated antibiotic compounds, it was determined that AZI was the compound that was least affected by the seasons in terms of the total removal efficiency obtained in WWTP. According to the annual average total removal efficiencies, it was determined that SMX (25.7%), CIP (71.3%), and AZI (89.2%) were treated poorly, moderately, and highly in WWTP, respectively. However, advanced biological WWTP was determined to be insufficient for the complete removal of total antibiotics.

Analysis of dust deposition law at the micro level and its impact on the annual performance of photovoltaic modules

Solar photovoltaic (PV) power generation is a promising clean energy technology, but dust affects its performance. This study, conducted in nine Chinese cities with varying climates and geographies, analyzed the physicochemical properties of dust and its deposition patterns at different inclination angles using microanalysis. Inclination angles were classified into three categories, and a dust density prediction (DDP) model was developed for each. The study also quantified the effect of different dust densities on PV module temperature in a controlled environment and created a PV module output power prediction (POPP) model to assess dust accumulation impacts on PV efficiency. It was found that dust insulation could increase PV module output power by 1.64 %–1.79 % at dust densities of 5–10 g/m2 and radiation levels of 400–800 W/m2. Combining the DDP and POPP models, a PV efficiency loss rate model was proposed to evaluate annual average PV efficiency and power generation losses at different tilting angles. Results showed an annual average PV efficiency loss of over 7 % at a 15° inclination angle and about 4.5 % at a 90° inclination angle. This study provides a framework for evaluating PV module mounting angles and cleaning intervals, optimizing solar energy systems for improved efficiency and returns.

Determining the influence of seasonal tilt angle on the efficiency of fixed solar photovoltaic modules

The object of this study is photovoltaic modules with different seasonal tilt angles at different geographical latitudes. The average annual efficiency of photovoltaic modules with different seasonal angles set at different geographical latitudes has been determined as the annual weighted average value of the cosine of the angle of incidence of solar rays on the plane of the photovoltaic module. The influence of seasonal tilt angles of photovoltaic modules at different geographical latitudes on their average annual efficiency was analyzed. Approximate values of the seasonal tilt angles of photovoltaic modules at different geographic latitudes take values that differ from the geographic latitude value by plus 15° for the winter period and minus 15° for the summer period. Modeling the average annual efficiency of photovoltaic modules depending on the seasonal tilt angles at different geographical latitudes made it possible to obtain refined values of the seasonal tilt angles of photovoltaic modules. Thus, at the latitude of 0°, 10°, 20°, 30°, 40°, 50°, and 60°, the tilt angle of photovoltaic modules for the winter period will be 14.8°, 24.6°, 34.5°. 44.4°, 54.1°, 63.6°, and 73°, respectively, and for summer ‒ minus 14.5°, minus 4.6°, 5°, 15.1°, 25.1°, 34.9°, and 44.7°. Dependences were obtained for determining the seasonal tilt angles of photovoltaic modules depending on the value of geographic latitude. The difference in the average annual efficiency of photovoltaic modules, which are installed at seasonal angles, and photovoltaic modules, which track the position of the Sun in the vertical plane, is 0.4 %. The results could be used as a basis for evaluating the efficiency of photovoltaic modules when determining the seasonal tilt angle at different geographic latitudes

Performance evaluation of standalone new solar energy system of hybrid PV/electrolyzer/fuel cell/MED-MVC with hydrogen production and storage for power and freshwater building demand

To achieve zero carbon emissions, increasing the scale of renewable energy implementation is imperative. Hydrogen is considered the prospective solution for sustainable energy due to its dual nature as a carbon-neutral fuel and an efficient storage medium for renewable energy sources. So, in this work, a standalone new hybrid energy system powered by solar energy for yearly power and freshwater production for building demand in New Borg El-Arab, Egypt. The system comprises photovoltaic (PV) panels, a water electrolyzer, multi-effect mechanical vapor compression desalination (MED-MVC), and fuel cells with hydrogen storage. A complete mathematical system model is built and solved by MATLAB/Simulink to study the daily, monthly, and yearly performance and sizing of the different system components based on the location climate conditions. The results indicate that PV panels of an area of 1824 m2, in conjunction with an electrolyzer, 863 fuel cells, and a storage tank capacity of 3013.4 m3can satisfy the annual building requirements of 255.17 MWh electricity, 766.5 m3 hot water and 876 m3 cold water. The maximum hydrogen storage lies between September and October, with maximum consumption between February and March. The average annual efficiency of PV, electrolyzer, fuel cell, electrolyzer output, fuel cell output, and overall hybrid system is 20.7%, 68.2%, 34.6%, 13.4%, 4.4%, and 16.5%, respectively, and the performance ratio (PR) of MED-MVC is 2.61. The system proves its capability to supply the building with electrical and water requirements with a levelized cost of energy (LCOE) equal to 0.712 $/kWh. Additionally, This system shows the potential to include other activities in remote areas or islands besides its contribution to achieving SDGs 6, 7, and 13.

Integrating Ray Tracing with Single-Objective Optimization in Heliostat Field Design

Tower solar thermal power generation is a new type of low-carbon and environmentally friendly clean energy technology. Through continuous optimization of the optical efficiency of mirror field and other key technologies, the energy utilization efficiency and economic benefits of solar thermal power stations can be improved, and contribute to the sustainable development of clean energy. This paper establishes a geometric model based on the light tracing method to solve the daily average, average annual optical efficiency, thermal output power, and average optical efficiency of the heliostatic field. The cosine efficiency is the cosine of the incident light and the normal angle, which is the cosine of the incidence angle; the atmospheric transmission is only related to the distance between the mirror center and the collector center; the mirror reflection constant is 0.92. The shadow occlusion efficiency and the truncation efficiency of the collector are the difficulties in the process of calculating the optical efficiency: for the calculation of the shadow occlusion efficiency, the Monte Carlo light tracing method is adopted. Based on the energy density of the helioscope, the occlusion efficiency of the shadow can be expressed as the ratio between the amount of the outgoing light to the total generated amount; for the calculation of the collector truncation efficiency, it links the reflected light with the surface equation of the collector. According to the joint results, if there is a solution, it means that the reflected light can be reflected in the collector, and the collector truncation efficiency can represent the ratio of the number of lights reflected in the collector to the number of unblocked lights in all the reflected lines. Finally, the average annual optical efficiency and output power parameters are respectively: 0.6093, 0.7431, 0.9283, 0.9828, 35. 4430MW, 0.5642kW/m². Results for the remaining months are shown in the main text.

Research on the annual average thermal power of heliostat field in tower solar energy

The concentrating mirror field is a concentrating and heat collecting subsystem in the tower solar thermal power station, and its optical performance directly affects the solar energy utilization efficiency of the power station. In this paper, the coordinate system of heliostat field and single heliostat is established, and the grid division technology is introduced to describe its reflection effect on sunlight and its occlusion. In this paper, the shadow occlusion loss that affects the optical efficiency is divided into three parts, including incident light occlusion loss, reflected light occlusion loss and absorption tower shadow occlusion loss. For any time, the output power of the heliostat near the solar direction is small, while the output power of the heliostat far away from the solar direction is large. Compared with other influencing factors, the cosine loss has the greatest influence on the heliostat field, and the center of the absorption tower installed in the circular heliostat field is obtained. The size of the heliostat is a square with a side length of 6m, the installation height is 4m, and the annual average optical efficiency is 0.6216 when the position of the heliostat is determined. The annual average output thermal power is 36.3958 MW, and the annual average output thermal power per unit mirror area is 0.5794 .

Evaluation and optimization of mariculture ecological efficiency under technological heterogeneity — New evidence from China's coastal regions

This paper combines the meta-frontier analysis framework with the SBM-DEA model based on undesirable outputs to thoroughly reveal the mechanism of ecological efficiency differences in China's mariculture. This paper accurately identifies the weak links in ecological efficiency in various regions, thereby achieving a precise evaluation of mariculture ecological efficiency within the framework of technological heterogeneity. The results indicate that under the meta-frontier, the annual average ecological efficiency of mariculture in coastal areas of China during the sample period is 0.586, with a 41.4 % efficiency improvement space. However, under the group frontier, the annual average ecological efficiency is 0.783. The MEI in the BR economic zone and the YRD economic zone respectively stem from MI and TI, whereas in the PRD economic zone, the difference in the proportions of management inefficiency and technological inefficiency is not significant. Finally, this paper proposes four types of improvement paths.

Transient analysis of an efficient solar assisted air-conditioning system for subtropical climate with various solar thermal collectors

The air conditioning demand of the world is largely fulfilled by vapor compression systems; however, these systems are also responsible for depleting ozone layer due to the nature of refrigerants. Desiccant cooling systems integrated with solar thermal energy technologies could be an attractive alternative with some performance enhancement techniques. In this study, transient seasonal performance investigation is performed for an innovative solar integrated desiccant cooling system that uses regenerative evaporative cooler known as solar assisted desiccant integrated Maisotsenko cycle cooler for better cooling performance. Furthermore, transient annual performance analysis of solar system for meeting thermal energy requirement for regenerating the desiccant wheel in summer season and handling heating load of the building in winter season is also carried out with three different solar thermal collector technologies for finding out more efficient technology. The key performance indicators in this study are useful energy gain, solar source efficiency, auxiliary energy sharing, coefficient of performance, and solar fraction. The results of the key performance parameters are reported as monthly average values. The proposed integrated system resulted to be very efficient with a maximum COP value of 1.13 in April when latent cooling loads are low and 0.78 in August when latent cooling loads are higher. The system’s maximum cooling capacity is 24 kW in April corresponding to a sensible heat factor of 0.720. Furthermore, the regeneration temperature requirements ranged from 50 °C to 78 °C, respectively that makes it favorable to use low grade thermal energy through non concentrating solar thermal collectors. The regeneration thermal energy requirement for desiccant wheel fluctuates throughout the year, maximizing in August due to higher dehumidification requirements. The study also revealed that the evacuated tube collector technology is most suitable with average annual efficiency of around 36 %.

Research on Heliostat Field Optimization Based on Monte Carlo Theorem and Randomized Algorithms

The text discusses a mathematical model established for calculating the optical efficiency of heliostat fields in solar power systems. It's grounded in geometric optics algorithms and considers factors affecting the field's optical efficiency. Each heliostat and the ground have independent coordinate systems for assessing whether light is blocked. The Monte Carlo method is utilized to determine the proportion of blocked light in reflected rays. This approach accommodates the conical nature of solar radiation, enhancing accuracy by transitioning from parallel to conical light representation. The results indicate an annual average optical efficiency of 0.5084 for the heliostat field, an annual average thermal power output of 30.879 MW, and 0.4915 kW/m2 as the annual average thermal power output per unit mirror area.

Research on Financing Efficiency of Intelligent Manufacturing Enterprises in China --Empirical analysis based on DEA-Malmquist modeling

Smart manufacturing is leading the way in the development of manufacturing quality in China. Based on the DEA-Malmquist model, this paper analyses the financing efficiency of 88 listed smart manufacturing enterprises in China from 2017 to 2021.The results of DEA static analysis show that: in terms of industry types, the comprehensive technical efficiency of the light textile industry is the highest, the resource processing industry has serious internal polarisation, and the machinery and electronic manufacturing industries are mainly affected by pure technical efficiency. Malmquist dynamic analysis shows that: the average total factor productivity index of listed enterprises in intelligent manufacturing is 0.9835, of which, the change value of pure technical efficiency leads to the annual average financing efficiency. The value of efficiency change leads to an average annual decline of 1.65% in financing efficiency. Therefore, the financing efficiency of Chinese intelligent manufacturing enterprises can be improved from the dimensions of improving the bond financing support system and constructing advanced manufacturing innovation system.

Determining the influence of mounting angle on the average annual efficiency of fixed solar photovoltaic modules

The object of this study is photovoltaic modules with different options for the angle of their installation to the horizon at different geographical latitudes. The scientific problem to solve was determining the dependence of the average annual efficiency of solar photovoltaic modules on the mounting angle of photovoltaic modules and the value of geographical latitude. It has been proven that the efficiency of installation of solar photovoltaic modules can be increased by reducing the angle of their inclination to the horizon depending on the value of the geographical latitude at which they are installed. The average annual efficiency of photovoltaic modules with different mounting angles to the horizon at different geographical latitudes was determined as the annual weighted average value of the cosine of the angle of incidence of solar rays on the plane of the photovoltaic module. The maximum of the average annual efficiency of photovoltaic modules corresponds to a smaller value of the angle of their installation to the horizon than the value of the geographical latitude. So, with a latitude value of 10°, 20°, 30°, 40°, 50°, and 60°, the mounting angle of photovoltaic modules to the horizon will be 9.5°, 18.8°, 28°, 37°, 45.8°, and 54°, respectively. A dependence was derived that allows determining the mounting angle of photovoltaic modules to the horizon dependent on the value of the geographical latitude at which they are installed. A mathematical expression was also constructed that makes it possible to determine the average annual efficiency of photovoltaic modules depending on the angle of their installation to the horizon for different values of geographic latitude. The results could be used in calculating the average annual efficiency of photovoltaic modules based on the adjusted values of the angle of their installation to the horizon at different geographical latitudes

Dual Substitution of Rural Energy Structure in China: Its Evolutionary Characteristics and Carbon Decoupling Effects

Accelerating the transformation of the rural energy structure is an indispensable part of energy transformation in developing countries. In this novel study, the transformation effect of China’s rural energy structure from 2001 to 2020 was evaluated. Further, this paper also identified the decoupling state between the rural energy structure transition and carbon emissions, and decomposed the spatial–temporal effects of rural carbon decoupling through efficiency measures. According to the survey, the dual substitution index of the rural energy structure in China increased from 0.466 to 1.828, and showed a decreasing trend in spatial distribution from the east to the central and western regions. Economic development and climate characteristics have become important influencing factors for the dual substitution of the rural energy structure. The decoupling relationship between the dual substitution of the rural energy structure and carbon emissions was mainly characterized in the strong decoupling, expansion negative decoupling, and strong negative decoupling states. Regional imbalances have deepened as the efficiency of rural energy carbon decoupling has gradually increased. The annual average efficiency of rural energy carbon decoupling in a dynamic perspective has increased by 10.579%, and the dual substitution of the energy structure has a significant driving effect on rural carbon reduction.

Annual performance study and optimization of concentrated photovoltaic-phase change material system

Concentrated photovoltaic (CPV) has the superiority of high efficiency and low cost. But the waste heat generated in PV cell has great effect on its performance. To study and optimize the real time photoelectric conversion performance, a two-dimensional PV model was firstly established. The impacts of concentration ratio and PV temperature on efficiency were investigated, and the correlation was derived. Based on that, phase change material (PCM) was utilized to realize temperature control of PV cell and a three-dimensional transient model for CPV-PCM system was established. The impacts of geometric parameters on the transient and annual performance were evaluated under the real climate conditions. The results show that concentration ratio has significant impacts on both thermal and electrical performance, and there exists an optimal concentration ratio to maximize the PV efficiency. At last, the system structure was optimized by orthogonal experimental method with annual average efficiency as the target. The optimal parameters combination was derived with concentration ratio of 300, PCM layer height of 60 mm, and fin number of 7. The validation results show that after optimizing, the maximum PV temperatures in summer and autumn are reduced by 9.4 °C and 7.4 °C, respectively, and the annual average efficiency of the system is improved by 1.83%.

Performance Analysis of 25kW p-Si Solar PV System

In present research project, the performance of a 25 kW electro-optical solar system consisting of 68 polycrystalline silicon panels with three models 310 watts, 320 watts and 400 watts was analyzed. The solar system was installed on Al-Zawraa Company buildings (Ministry of Industry and Minerals, Baghdad). An evaluation of the performance of the on-grid solar system was carried out under the skies of Baghdad. This solar system is synchronized with the 0.4kV low voltage distribution sector and its annual performance is measured. During the observed period, the annual output energy was 20921 kWh. The rate of daily yield of array, final yield and reference yield were 2.34 kWh/kWh, 2.29 kWh/kWh, and 5.94 kWh/kWh, respectively. The results also indicated that the annually average daily total losses, array losses and losses of the system were 3.65 kWh/kW, 3.61 kWh/kWh, and 0.046 kWh/kWh, respectively, while the annual average efficiency of inverter, system and arrays was 98%, 6.45% and 6.56%, respectively. The annually average of capacity factor and performance ratio were 30.8% and 38.6%, respectively.