Design and simulation analysis of 130 KWp grid-connected solar PV system using PVsyst: A case study in Egypt.

This paper presents a feasibility study using a PV system grid-connected photovoltaic design that satisfies a 130 KWp grid’s electrical needs for a local factory in Al Obour City, Egypt (Coordinates 30.19373, 31.44213). This system has been mounted on a fixed tilt mounting structure. The system comprises a photovoltaic array to capture solar energy. The modeling is accomplished by evaluating the required load and selecting and deciding the proper specifications of the components inherent in the system. Several constituents, such as the geographic area, atmospheric condition, solar irradiance, and load consumption, are analyzed and discussed for the whole work. The system produces 212.7 MWh each year. The cost of the system can be enhanced by variable system parameters such as net present one, initial capital one, energy cost, and operating expense. Further, the techno-economic analysis of the suggested system has been performed using PVsyst simulation software. The simulated results reveal that the proposed model meets the load demand, reducing the monthly bill by ~20 %. The PVsyst proves an easy, speedy, accurate, dependable, well-grounded software tool for the simulation of the solar PV system.


Introduction
The continuous increase of worldwide energy demand, combined with the near exhaustion of fossil fuels such as coal, oil, gas, and uranium and the significant environmental damage, has initiated a dramatic increase in the need to use and develop renewable energy sources technologies.Fossil fuels generate most of the energy consumed in Egypt, while the future government is committed to making Egypt more independent and greener.Renewable resources such as solar energy are much used for electricity generation due to their availability and the fact that they are associated with no greenhouse gas emissions.Solar energy should be a promising free natural source among other renewable resources.Indeed, the earth receives around 3.8×10 18 MJ of solar energy based on a mediocre of almost 5000 times exceeding the world's consumption [1,2].Solar energy is the most easily possible, non-polluting, and has relatively low maintenance expenses.It has drawn much attraction, especially with the constant fluctuation in grid electricity supply.Egypt is in an advantageous position with solar Energy.The sunshine lasts, on average, 10 hours/day, with plentiful sunny days and a few clouded ones throughout the year.The DLR has made an estimate of Egypt's economically endorsed great potential for solar energy sources to be about 73,700 TWh/year [1].The size of the Egypt PV Market is expected to expand from 2000 MW to 3,500000 MW from 2023 to 2028, respectively.A solar power plant is designed to convert sunlight into electricity.This can be done directly or indirectly using photovoltaic (PV) or concentrated solar power.It has been predicted that PV systems will be subject to an overall increase in decades.Nevertheless, the prosperous amalgamation of solar energy industries into the existing energy structure is built upon in-depth information and understanding of the availability of solar resources in precise districts and areas.The expand in PV installed capacity has triggered a continued expansion of the power conversion of the photovoltaics [3,4].The photovoltaic conversion business has evolved rapidly from its inception within the last 25 years.On the one side, this progress has been due to the PV converter market's rigorous specifications, such as high efficiency of above 95%, continued warranty durations, high power quality, transformerless operation, leakage current reduction, and unique control requirements for maximum power point tracking.On the other hand, possessing this development, for the long term, the power converter represented only a tiny fraction of the cost of the whole PV system due to PV modules' higher prices, permitting PV inverter manufacturing to develop high-performance and more refined and advanced topologies.Three PV system types exist: off-grid, on-grid, or hybrid.A layout of a generalized gridconnected photovoltaic system is given in Figure 1.Such photovoltaic cells can produce electrical energies that can be supplied into the electrical network based on pre-defined quality and reliability characteristics.This should be unaccompanied by harm to the regular operation of the network.An inverter is used to connect the PV array to the electrical network.It transforms the DC output of the array of PV panels to an AC output waveform that matches the local network's voltage and frequency.It is worth noting that the system, as illustrated in Figure .1, excluding any facility for energy storage.This is the standard configuration of a great deal of current grid-connected photovoltaic systems [5,6].Several simulation software have been developed to assess a photovoltaic system's performance and economic potential to make the design process more manageable and simplified and boost energy applications, in particular, the renewable energy industry, such as SAM, PVsyst, HOMER, RETScreen, Solarius PV, PV Geographical Information System (PVGIS), HelioScope, Solar Pro, SOLARGIS, PV F-Chart [7][8][9][10].PVGIS and PVsyst have been widely used to investigate and design the PV system's energy production, the latter will be considered in this study.Okello et al. conducted research in 2015 [11] to analyse and simulate a 3 KWp grid-connected system in South Africa.The paper compares the simulated performance with the actual measured performance.The system subsets of 14 polycrystalline modules are connected in two strings.The results of this experiment are impressive.The researchers measured the power for a year, which helped collect data efficiently.The estimated AC power output for the entire year is 5771 kWh/year, while the simulation expected the outcome to be 5755 kWh/year [11], which is quite the same.This shows how PVsyst is very efficient at predicting the values for the whole system.Kumar et al. [13] studied a 100 KWp grid-connected system installed in India.They represented the performance of the PVsyst simulated system in comparison to the practical results of the project after construction.The performance ratio of the system was 74%, and the efficiency was 9.27%; the energy output ratios were different; PVsyst simulated the value to be 823 kWh/kWp, and the actual measured value was 812.76 kWh/kWp [12].In 2014, a 2 kW off-grid system simulated the project using PVsyst, built in Sharjah, UAE-the project aimed to test the significance of shading and its effects on the system.The system's performance is analyzed, and it was found that the shading limits the system's performance [13].Another paperwork presented an expedited investigation of implementing an on-grid PV system for the electrification of Cedars Hotel in Jordan.Considering Jordan's electrical load and solar energy demand, the PV system was designed.The actual consumption energy of this building has been estimated at 444 MWh/year.The design and simulation work of the on-grid PV system is executed using (PVGIS) Photovoltaic Geographical Information System software and photovoltaic software (PVsyst).The simulation output shows that the average PV system could generate about 38 MWh per month.The needed zone to install the PV system was 1757.3 m 2 , which could be facilitated at the hotel's garage area.The performance ratio analysis shows an average annual PR of almost 81%.[14].
This paper aims to attend the design, modeling, and analysis of a 130 KWp grid-connected rooftop solar power project for a local factory in Al Obour, Cairo, Egypt.The study estimates the electricity generated, the efficiency of the photovoltaic (PV) power system, and the economic indicators of the project.

Components and Methods
The PVsyst is a powerful simulation approach that facilitates several options, such as designing a gridconnected and standalone PV system.A particular design area can be selected by the user and alleviated for a solution based on the requirement.The software is also convenient to give an initial design for marketing and promoting the PV system installations to consumers.The detailed design is for solar installers, and it can generate results such that, following the simulation results, one can commence the process of setting up a solar PV plant.The project in this research is for the Al wefak Alsaudi factory in Al Obour, Cairo, Egypt, coordinates 30.19373 and 31.44213, as shown in Figure 3.The PV systems have been mounted on the rooftops of the building.The system's total number of modules is 298 modules.The PV system connections consisted of 19 strings connected to two Huawei inverters, Inverter 1 with a capacity of 60 K and inverter 2 with a capacity of 50 k, with a 98.9 % efficiency and comes with six MPPTs (maximum power point tracker) and 12 female input connectors that helps increase the efficiency of transforming the DC power that comes from the modules to AC and this is the primary function of the inverter.Figure 2 represents the central estimation of the electricity generation of the simulation.The plant consists of four different areas, and each site has a different orientation.The total number of modules is 298 to reach a total power of 130 KWp.Two inverters regulate the power with capacities of 50 KW and 60 kW, respectively.The system produces 212.7 MWh each year without including the degradation rate of the solar panels.The system produces energy with a performance ratio of 80.04 %.

Data Collection, Analysis, and Discussion
Figure 4 illustrates the yearly production of the system, and the different colors represent the proper production and the losses.As the Figure 4 describes, June is when the system produces the most energy over the year, but this does not mean the system is the most efficient.The significant performance parameters are the performance ratio and the specific yield.The latter one can be estimated as: YF often denotes it.The performance ratio is expressed as actual energy to the energy output, achievable by theory.It measures the quality and the attributes of a PV plant independent of the location, and it is, therefore, often described as a quality factor.The performance ratio (PR) is defined as the actual energy versus the theoretical energy outputs of the PV plant, as expressed below in Equation 2. A good, efficient solar plant should have an 80 % or higher performance ratio.

𝑃𝑅 = 𝐴𝑐𝑡𝑢𝑎𝑙 𝐸𝑛𝑒𝑟𝑔𝑦 𝑓𝑟𝑜𝑚 𝑃𝑙𝑎𝑛𝑡 (𝐾𝑊ℎ) 𝐶𝑎𝑙𝑐𝑢𝑙𝑎𝑡𝑒𝑑 𝑁𝑜𝑚𝑖𝑛𝑎𝑙 𝑃𝑙𝑎𝑛𝑡 𝑜𝑢𝑡𝑝𝑢𝑡 (𝐾𝑊ℎ)
(2) Figure 5 displays the performance ratio of the system yearly.At first glance, it can be assumed that the highest PR occurs during the summer or when the system receives more sunlight.Still, this duration has the lowest performance ratio because system losses increase during this time of the year due to the rising temperature of the summer, and losses are directly proportional to the number of photons received by the modules.An immediate and insightful overview of the quality of a PV system design can be deduced from the loss diagram by figuring out the primary sources of losses.The array losses begin with evaluating the nominal energy, using the global effective irradiance and the array nominal efficiency at STC.Then, it details the PV model behavior in accordance with the environmental variables.Figure 6 describes a diagram of the losses of the rooftop solar power system.The losses include, for example, the soiling losses, which is the accumulation of dirt, and its effect on the system performance is an uncertainty that strongly depends on the system's environment and rain conditions: the Irradiance losses, the Thermal losses, the Module quality losses, and the Array mismatch losses.The inverter losses (IL), which reflects the power difference between the MPP of the arrays I⁄V curve and the adequate power of this operating point, accounted as inverter loss: IL during operation, IL over nominal inverter power, i.e., overload loss, IL caused by voltage threshold, IL over nominal inverter voltage, i.e., when the array MPP voltage is over Vmpp.And IL due to the maximum input current.The graph depicts the energy input and output, including bit-by-bit loss analysis.The Sankey diagram is a handy tool for examining plant efficiency.As shown in the simulation, 212.7 MWh is the energy injected into the grid.The array's nominal energy is estimated at 243 MWh.Hence, a difference of 30.3 MWh is the total loss of the system.The system reveals an efficiency of 20.22% under the STC conditions.It can be observed that soiling has the most significant effect on losses because of the surrounding environment and the site's location.This is due to the project being a production site, and the panels are more exposed to dust than in other residential locations.The second main contribution is the temperature losses, and this is because resistance increases with temperature, and PV losses are directly proportional to temperature.The heat loss is high because the local factory is located in an area with a high temperature compared to the standard conditions inside the city.An additional total inverter loss of about 2% can be noticed.Figures 7 (a) and (b) represent the actual output powers produced over eight days in July by the system and went through the two inverters 60 KW and 50 KW.It is also worth to mention that, on the second day, the system was in half power, and on day three, the system was off.The total cost savings over seven days are equivalent to 2050.9 pounds and 1646.0 pounds (or its equivalent) deduced from the 60 Kw and 50 Kw inverters, respectively.The data was collected from the inverter and sent to a mobile phone by the (Sun 2000) application, which Huawei supplies.The results present that the proposed model meets the load demand.It is estimated that on summer days, such as day one in Figure 7 (a), the bill's reduction is about 80%.The PVsyst proves to be an easy, fast, accurate, and honest technique for the simulation of the solar PV system.

Conclusions
Energy is a significant driver of modern economic development.Egypt processes massive solar energy resources and has excellent potential for PV projects to meet this energy demand.In this article, a proposed PV power plant is planned to meet the load of a local factory in Al Obour City, Egypt (coordinates 30.19373, 31.44213).The study emphasized simulating a 130 KWp solar-based PV system.It explained the design procedure to ease the issues of selecting PV modules, the size of the inverter power, the selection of districts and locations, and string arrangement.This paper is a reference tool to investigate the installation aspects of grid-connected systems.Additionally, various losses in the system can be accurately estimated with the help of PVsyst software.The significant merit of the PVsyst is that it can initiate a comprehensive installation report and explore the power output and losses in the plant.

Figure 4 .
Figure 4. Nominal Power Chart of the system over the year.

Figure 5 .
Figure 5.The obtained performance ratio of the system yearly basses.

Figure 6 .
Figure 6.Loss diagram of the grid-connected PV system.

Figure 7 .
Figure 7. (a) and (b) The actual output powers from inverters 60 KW and 50 KW, respectively.The results are the AC power produced by the PV systems.