Technical Performance and Economic Feasibility Simulation of 200kWP Rooftop Solar Photovoltaic On grid on Industrial Estate Factory Building with Helioscope Software

—Renewable energy resources are currently being developed by Indonesia. The government is also targeting an energy mix of 23% to achieve renewable energy by 2025. One of the renewable energies is Solar Photovoltaic Generation System. On the other hand, an industrial area is an area filled with factories that are large enough so that it has great potential to develop Rooftop Solar Photovoltaic with the advantage of reducing land investment costs without reducing the operational function of the factory. The purpose of this research is to simulate the technical and economic performance of a 200kWP Solar Photovoltaic On grid on the rooftop of a factory building using Helioscope software in an industrial area in West Java. The simulation result shows that the average values for Global Horizontal Irradiance (GHI), Electrical Energy Production, and Performance Ratio (PR) in one year are 138.2 kWh/m2, 21,977 kWh, and 78.06%. Meanwhile, the total Electrical Energy Production in one year is 263,723.6 kWh. The total investment value of the 200kWP Rooftop Solar Photovoltaic On grid on the factory building is 2,457,850,800 IDR. Based on the economic feasibility study, it can be concluded that the 200kWP Rooftop Solar Photovoltaic On grid on the factory building rooftop is economically feasible as long as the interest rates is less than 12.71% (Internal Rate of Return / IRR).


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Dhami Johar Damiri and Achmad Aditya Nugraha: Technical Performance and Economic Feasibility Simulation of 200kWP Rooftop Solar Photovoltaic On grid on Industrial Estate Factory Building with Helioscope Software hours per day [6]. With an area of + 9.8 million km 2 , the potential for electrical energy that can be generated by solar energy reaches 47 million GWh / day [7] [8]. For this reason, solar energy is a renewable energy source that has enormous potential.
On the other hand, industrial estates are areas filled with buildings and factories that are large enough to have great potential for developing solar power plants. The solar power plant can take advantage of the factory roof so that it can reduce the cost of land investment without reducing the operating function of the factory. The development of Solar Photovoltaic on the factory roof also has advantages when compared to large-scale Solar Photovoltaic that is easier and cheaper integration with existing electricity systems, reduces land investment costs, reduce the use of electrical energy from electricity supply companies, and reduce greenhouse gas emissions [9]. The government is also serious in developing Rooftop Solar Photovoltaic, especially in industrial areas with the issuance of PERMEN ESDM NO. 49/2018 jo. PERMEN ESDM NO.13 / 2019 jo. PERMEN ESDM NO. 16/2019 which regulates in terms of installation, operating permits, and transactions with PLN as electricity supply companies in Indonesia [9]. For this reason, study in the development of Rooftop Solar Photovoltaic in Industrial areas is very necessary.
Previous study conducted by DJ Damiri et al. in 2019 discussed the design of the 52.5 kWp Rooftop Solar Photovoltaic On grid on the roof of a factory building in the West Java industrial area. The analysis made includes a technical simulation of the Solar Photovoltaic performance [10]. Another study conducted by M.R. Wicaksana et al. in 2019 also discused the design of solar photovoltaic 158kWp on Bali's government office [11]. However, this study has not discussed the economic feasibility study of the design. This economic feasibility study is very important to do, especially in determining the decision making whether a project will be invested or not [12]. Therefore, in this study a simulation of the technical performance and economic feasibility of a 200 kWP Rooftop Solar Photovoltaic will be made using the Helioscope software on the roof of a factory building in an industrial area in West Java. The parameters to be used are Global Horizontal Irradiance (GHI), Total Electrical Energy Production, and Performance Ratio (PR) as a result of simulation using Helioscope software and by adding the calculation and analysis of economic feasibility study.
The approach taken to determine the economic feasibility refers to study conducted by Camilo et al in 2017 and I.B.K Sugirianta et al in 2016, where the Life Cycle Cost method is used to determine the economic feasibility of a project as a further analysis of whether the design of the project is economically feasible and profitable or not [13] [14]. This method calculates the overall cost consisting of planning, project execution, Operation&Maintenance, replacement, and salvage value over the life of the system. The parameters which be calculated is Levelized Cost of Energy (LCoE), Net Present Value (NPV), Internal Rate of Return (IRR), Profitability Index (PI) and Discounted Payback Period (DPP).

II. Method / design
This study was conducted in PT XYZ factory building in an Industrial Estate in West Java. This factory has a power contract capacity of 200 kVA to PLN (the rates of group B2 / Low Voltage). Based on the Minister of Energy and Mineral Resources regulation number 49 of 2018, the maximum capacity of the rooftop solar system is 100% of the customer's connected power [9]. So in this study the capacity of 200kWp solar photovoltaic was chosen to maximize the potential of the factory building roof top.
Previous study conducted by I.H.Rosma et al in 2018 discussed about the optimum solar photovoltaic energy production using sun tracker. The purpose is to get the optimum solar radiation based on the direction of the sun. It can be seen from the results that using sun tracker could increase the energy production 20%-60% [15] [16]. Research on the factory building rooftop was carried out on the north side of the building to get optimum solar energy radiation because the West Java industrial area is located on the south of the equator line.
In general, the steps in this study are: 1. Retrieval of data (location on google maps, the area of the factory roof, and the placement location of electrical equipment and inverters In order to calculate the technical performance parameters of solar photovoltaics, meteorological parameters are needed to obtain accurate simulation results for each specified location [17]. These data include solar radiation, air temperature, water relative humidity, wind, etc. In this study, Helioscope software was used in which there was already complete meteorological parameter data spread across all locations on earth. Helioscope is a WEB based program released by Folsom Labs. We can determine the study approach in calculating the performance of Solar Photovoltaic, that is an approach by determining the total power of the system or an approach by utilizing the total available area. In this study, the approach taken is to determine the total power of the system, which is 200 kWp [18].
Helioscope analyzes using weather data from meteonorms which provides accurate and representative data with more than 30 different weather parameters for typical year data, has more than 8,000 weather station data, 5 geostationary satellites, and aerosol climatology that is globally calibrated [19].
Technical databases are also available on Helioscope such as solar modules and inverters. Array configurations can also be made in the program. The simulation results will provide Solar Photovoltaic performance parameters, namely Global Horizontal Irradiance (GHI), Total Electrical Energy Production, and Performance Ratio (PR), as well as other supporting parameters [20].

Global Horizontal Irradiance (GHI)
Global Horizontal Irradiance (GHI) is the total solar radiation on a horizontal surface. Basically, this GHI is the sum of Direct Normal Irradiance (DNI), Diffuse Horizontal Irradiance, and radiation reflected from the ground [10] [21]. The unit of GHI is kWh / m 2 .

Total Electrical Energy Production
The total electrical energy production of a Solar Photovoltaic is the result of the sum of the AC current generated by the system for a certain duration of time [10]. The unit of the total electrical energy production of Solar Photovoltaic is kWh.

Performance Ratio (PR)
Performance Ratio (PR) is the quotient between the total AC electrical energy of Solar Photovoltaic and the theoretical calculated output of Solar Photovoltaic with the assumption that the Irradiance received is converted into electrical energy according to the generating capacity. PR is fully defined in IEC 61724 [10]. The complete PR can be calculated with the following equation: The overall losses from Solar Photovoltaic such as module losses, reduced low light efficiency, temperature, inverters, shading, cables, and fouling are included in the factors calculated in PR [20].
In calculating the economic feasibility study, the following parameters are used:

A. Levelized Cost of Energy (LCoE)
Levelized Cost of Energy (LCoE) is the cost of electrical energy generated from a certain energy source to reach break even for a certain period of time. Usually the time period is determined based on the life time of a generating system [10] [14] [22].
To calculate LCoE, Life Cycle Cost modeling is used. Life Cycle Cost Modeling is modeled by the United States Department of Energy and regulated in the National Bureau of Standards, 1980. This model considers the total relevant costs of an energy system ranging from design costs, civil buildings, materials, components and operating costs, especially the initial investment costs, maintenance costs, future equipment replacement costs, security, insurance value and salvalge value [10] [14].
The LCoE equation is as follows:

C. Internal Rate of Return (IRR)
Internal Rate of Return (IRR) is the interest rate where total income in present value with total expenditure / investment in present value will be the same, in other words, the interest rate where the NPV parameter is equal to zero. [13] [14]. The IRR equation is as follows: If IRR> i u then the project is economically profitable, on the other hand, if IRR <i u then the project is rejected (i u = the prevailing general interest rate).

D. Profitability Index (PI)
Profitability Index (PI) is the ratio of income in present value with expenditure in present value [13] [14]. The PI equation is as follows: If PI> 1 then the project is economically profitable, on the contrary, if PI <1 then the project is rejected

E. Discounted Payback Period (DPP)
Discounted Payback Period (DPP) is the time required to return investment costs from future income by considering the time value of money [14]. The DPP equation is as follows: When the DPP <n, then the project can be done (n = time required).

A. The study location details
This study was conducted in a factory building located in the industrial area of West Java with latitude 6.3 0 S and longitude 107.1 0 E. The location of the roof of the building as a study location is shown in Figure 1, namely North Building A and North Building B with total dimensions in each building is 105 meters long and 15 meters wide with an area of 1,575 m 2 . So that the total area of the factory building roof for study is 3,150 m 2 . The roof height from the ground is 11.5 meters with the slope of the roof angle is 10 0 , while the azimuth angle of this building is -20 0 . The The location of inverters and other electrical equipment such as AC Panel and Solar Monitoring in the west side of the building is shown in Figure 2.

B. 200kWp Solar Photovoltaic design plan on the factory building rooftop
The Solar Photovoltaic system is planned to be installed with a total capacity of 200.22 kWp using a Solar Photovoltaic module with a capacity of 355Wp , total of 564 units, with the type of module is REC TWINPEAK 2S72 355Wp as seen in Figure 3. The Solar Photovoltaic will be connected to 3 inverters with a capacity of 66kVA with the type of inverter is Conext CL-60E Schneider. The total number of strings connected to the 3 inverters is 32 strings with each string 17 to 19 Solar Photovoltaic modules arranged in series. The monitoring tool used is Solar Log 2000 with monitored data including irradiance, ambient temperature, and module temperature.
In civil design, the Solar Photovoltaic module placement will use the Klip-lok system with L-Bracket. Detailed appearance of how to install the module is presented in Figure 4.
With the Solar Photovoltaic design plan as explained   From the simulation results obtained from the Helioscope software, it shows that the energy production results from Solar Photovoltaic are very dependent on the   Figure 9 where the correlation between GHI and Energy Production has a value of 0.970 which means it has a very strong positive correlation, which means that the greater the GHI value, the greater the value of energy production obtained.
The Performance Ratio value is the overall value of Solar Photovoltaic losses in the form of module losses, reduced low light efficiency, temperature, inverters, shading, cables, and impurities/dust. From the simulation results obtained in Figure 10, it can be seen that the temperature in the Solar Photovoltaic module is the biggest factor that contributes to system losses, which is 12.4%. Base on this situation, the study is continue to analyze the correlation factor between the module temperature and the PR obtained from the Helioscope simulation results. The results in Figure 11 show that the correlation between the temperature of the Solar Photovoltaic module and the PR is -0.571 which means it has moderate negative correlation, meaning that the greater the module temperature value, the PR value tends to decrease. production uses the applicable electricity rates from PLN which similar with the rates of group B2 / LV, which is 1,467.28 IDR/kWh [28] because the electrical energy produced by Solar Photovoltaic is used for its own use in order to reduce the use of electrical energy from the electricity supply companies.
From the data above, a project cash flow can be made during the life time of the Solar Photovoltaic system as seen in Figure 12.
From the project cash flow, the Economic parameters can be calculated and the result is shown in Table 1. The value of LCOE, DPP increase and NPV, PI decrease when the interest rate value increases. It means that interest rate value affect the economic feasibility result. The profit of the project when uses the own capital will be higher than when uses the bank loan capital. The limit of the interest rate that is allowed to keep the project feasible is by looking at the value of the IRR. From the calculation results, it can be seen that the IRR value is 12.71%. For this reason, if the interest rate is more than the IRR value, it can be ascertained that the economic feasibility study of the project is not feasible.
Based on the economic feasibility limitations which has been stated earlier in the Method / Design chapter, it can be concluded that the 200kWP Rooftop Solar Photovoltaic On grid on the factory building rooftop with the rates of group B2 / LV is economically feasible as long as the interest rates is less than 12.71%. The most optimum investment is obtained when the interest rate uses 0% or when the investment prices uses own capital.

IV. Conclusion
From the study results, it was found that the simulation of technical performance and the calculation of economic parameters for 200kWp Rooftop Solar Photovoltaic On grid on the factory buildings rooftop in industrial areas has been successfully carried out on the rooftop building with the total area used is 3.150 m 2 , the roof height from the ground is 11.5 meters with a slope of the roof angle is 10 0 , while for the azimuth angle of this building is -20 0 . The Solar Photovoltaic module is installed using the Kliplok method with L-bracket by adjusting with the shape of the roof at the study location. The total capacity of Solar Photovoltaic is 200.22 kWp by using a Solar Photovoltaic module with a capacity of 355Wp and total 564 pieces using REC TWINPEAK 2S72 355Wp type. The Solar Photovoltaic is connected to 3 inverters with a capacity of 66kVA using Conext CL-60E Schneider inverter. The total number of strings connected to the 3 inverters is 32 strings with each string 17 to 19 Solar Photovoltaic modules arranged in series. The monitoring tool used is Solar Log 2000 with monitored data including irradiance, ambient temperature, and module temperature.
The technical performance simulation of the 200kWp Rooftop Solar Photovoltaic On grid on the factory building rooftop has an average GHI and Electrical Energy Production with value 138.2 kWh/m 2 and 21,977.0 kWh with total electrical energy production of 263,723.6 kWh in one year. The Performance Ratio (PR) of the 200kWp Rooftop Solar Photovoltaic On grid has an average PR in one year of 78.06%. The energy production results from Solar Photovoltaic are very dependent on the irradiance value of sunlight with a correlation value of 0.970 which means that it has a very strong positive correlation, meaning that the greater the GHI value, the greater the energy production value obtained. The PR value itself is a factor that shows the total system losses as a whole system where the temperature in the Solar Photovoltaic module is the biggest factor that contributes to system losses, which is 12.4%. The correlation value between the temperature of the Solar Photovoltaic module and the PR is -0.571 which means that it has moderate negative correlation, meaning that the greater the temperature of the module, the PR value tends to decrease.
The total investment value of 200kWp Rooftop Solar Photovoltaic On grid on the factory building rooftop is 2,457,850,800 IDR. Based on the economic feasibility calculation, it can be concluded that the 200kWP Rooftop Solar Photovoltaic On grid on the factory building rooftop with the rates of group B2 / LV is economically feasible as long as the interest rates is less than 12.71%. The most optimum investment is obtained when the interest rate uses 0% or when the investment prices uses own capital.
This study only focuses on one study location and with a fixed capacity of 200kWp. For further study, it can be carried out for several locations and several variations in the capacity level of Solar Photovoltaic so that in the end it can be further developed, especially in the preparation of standardized Rooftop Solar Photovoltaic designs for industrial estates both in terms of technical performance and economic feasibility aspects.
This study also focuses on design, technical performance and economic feasibility simulation of 200kWP rooftop solar photovoltaic on grid. The current study has not explained further about the potential for saving electrical energy that can be generated from solar PV by comparing the electrical energy from solar PV and PLN. For further studies, the calculation of electricity savings and the calculation of the potential for carbon footprint reduction can be carried out to be able to provide further information on the advantages of developing solar PV, especially in industrial estate areas.