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Design of Electrical Lighting Installation in a Simple House with Solar Panels

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1.Introduction

Energy is a vital element in today's global context. Significant population growth has had a direct impact on the increase in energy demand across various segments of society [1]. To date, most energy needs are still met by fossil fuels, which are known to have negative impacts on the environment [2]. As a result, there has been a growing public awareness of the need to seek more environmentally friendly alternative energy sources, namely renewable energy. One form of renewable energy with great potential for implementation in Indonesia is solar energy.

Indonesia, with its geographical location near the equator, has enormous potential for the development of solar power plants (PLTS). This potential is not only promising for meeting energy needs but also contributes significantly to efforts to reduce carbon emissions [3]. Solar energy is a renewable and inexhaustible energy source that can be converted into electricity through solar cells [4].

Since the early 1970s, solar cell technology has undergone rapid development, shifting the paradigm of electricity generation away from the previously dominant fossil fuel sources such as petroleum, natural gas, coal, or nuclear reactions [5]. Solar energy is recognized as a highly environmentally friendly energy source, as its conversion process produces no pollution and offers long-term sustainability. Photovoltaic (solar photovoltaic) cells are increasingly in demand due to their flexibility across various applications, including in offices, factories, residential buildings, and other sectors [6].

The process of generating electricity through solar panels involves a series of systematic steps, from the absorption of sunlight to its distribution to consumers [7]. The power generated by solar panels is highly dependent on the intensity of sunlight, so the voltage produced can vary. Therefore, careful planning is necessary to determine the capacity of a solar power plant to meet electricity needs. Evaluating the efficiency of each alternative energy source is also crucial for maximizing system performance.

The application of solar energy technology to meet electricity needs in remote areas can be achieved through various solar power generation systems, including hybrid systems that combine solar energy with other energy sources [8]. One example of such a system is the Solar Home System (SHS), which consists of solar modules, batteries, a controller, and lighting fixtures. This system can be installed in any home with solar panels mounted on the roof.

Renewable energy comes from sustainable natural processes, such as solar energy, wind energy, water flow, biological processes, and geothermal energy [9]. In the context of new and renewable energy sources, the primary focus is on converting solar energy into electrical energy. The capacity for solar energy conversion depends on the area of the solar cells used, and the utilization of these solar cells can be optimized. This study aims to design a 20 Wp solar power plant, with a focus on improving the conversion efficiency from input to output voltage.

2.Method

This chapter aims to provide a theoretical basis and references that support research on the design of electrical lighting installations with 20 WP solar panels. Through a literature review, this study will explore various aspects related to solar panels, including their working principles, types of solar panels used, and their application in simple residential lighting systems. This study will also review the evolution of solar panel technology, from basic concepts to its increasingly widespread use in various fields, such as lighting, irrigation, and electricity supply in remote areas. This review will also include an explanation of the components of a solar panel system, such as an inverter, battery, and solar charge controller, along with their functions and advantages in supporting system efficiency.

2.1.Solar Cells (Photovoltaic)

Solar cells, also known as photovoltaic (PV) cells, are semiconductor devices that can convert solar energy directly into DC electrical energy. This process is based on the principle of the photovoltaic effect, where photons (light particles) emitted by the sun free electrons from atoms in semiconductor materials, thus producing an electric current [10]. The most common material used in solar cells is silicon, which is processed into cylindrical crystals. These silicon cylindrical crystals are heated with a regulated pressure so that the silicon turns into a conductor. Furthermore, the cylindrical crystals are cut into thin sheets with a thickness of about 0.3 mm, forming thin silicon cells or known as solar cells [11].

These silicon cells are installed in parallel or series in a solar panel. Solar panels are typically made of materials such as aluminum or stainless steel, and are protected by glass or plastic to protect the cells from physical and environmental damage. At each junction between cells, a different potential is given, called a depletion region. This area serves to separate electrons and holes created when photons release electrons, thus allowing DC electric current to flow [12].

When solar panels are exposed to sunlight, photons emitted by the sun enter the solar cell and release electrons from the silicon atoms. These electrons then move through the depletion region, producing a DC electric current. The DC electrical energy generated by solar panels is typically used to meet direct electricity needs, or it can be converted into AC electrical energy using an inverter for use in a household electrical system or larger power grid [13].

Solar panels have several advantages as an energy source. First, solar panels are a very practical and environmentally friendly source of energy. They do not require conventional power grid infrastructure, so they can be installed modularly in a variety of locations, including remote areas that are not yet served by the power grid. Second, solar panels have a long service life and require minimal maintenance, making them an economical solution in the long run. Third, the use of solar panels can reduce dependence on fossil fuels, thereby contributing to the reduction of greenhouse gas emissions and environmental pollution. Thus, solar panels are a very important technology in an effort to meet the needs of electrical energy in a sustainable and environmentally friendly manner [14]. Fig. 1 shows the solar panels and Table 1 shows the specifications of the solar cells used (20 WP).

2.2.Current and Voltage Characteristics of Solar Cells

The current received by a solar cell in a single day varies greatly. This is due to the difference in the intensity of sunlight, which is greater during the day compared to the morning. To find out the power capacity produced, measurements are made of the current (I) and voltage (V) in clusters of solar cells called modules. To measure the maximum current, the two terminals of the module are made in a circuit of short circuits so that the voltage becomes zero and the current is maximum. Using an amperemeter, the maximum current measured is called short-circuit current (Isc). Voltage (V) measurements are performed on the positive and negative terminals of the solar cell module without connecting them with other components. This measurement is called open-circuit voltage (Voc). The results of the current (I) and voltage (V) measurements can be depicted in a graph called the I-V curve, as shown in Fig. 2 below.

2.3.System Design

In the system design sub-chapter, the researcher compiled a technical and functional blueprint of the solar power plant system (PLTS) for simple residential house lighting installations. This design began with the selection of polycrystalline type solar panels with a peak capacity of 20 watts (WP) due to their fairly high efficiency and wide availability in the market. This research involves the use of inverters that are able to convert DC electric current into AC electric current with a voltage of 220V and a frequency of 50 Hz, according to the needs of household electrical appliances. The system is also equipped with a 7.5 Ah capacity Valve Regulated Lead-Acid (VRLA) battery to store the electrical energy generated by the solar panels, ensuring power availability at night or during cloudy weather.

The energy security system is designed with a charging and battery management mechanism controlled by a Solar Charge Controller (SCC) based on Maximum Power Point Tracking (MPPT). This SCC ensures battery charging efficiency and prevents overcharging, thereby increasing battery life. As an additional layer of security, the system is equipped with voltage monitoring using a digital multimeter. Fig. 3 shows a block diagram of the system, with the addition that the black arrow direction indicates the DC power line, while the red arrow direction indicates the inverter's AC 220 power line.

The wiring diagram in Fig. 4 shows a solar power system consisting of a 20 WP solar panel, a Solar Charge Controller (SCC), a battery, an inverter, and three 3-watt lights. Solar panels convert solar energy into DC electricity, which is managed by SCC to charge the battery efficiently and prevent overcharging. The DC electricity from the battery is then converted by the inverter into AC electricity to power the lights. DC electrical currents are marked with black and red lines, while AC electrical currents are depicted with blue and orange lines. This diagram clearly depicts the relationships between the components to ensure system efficiency.

3.Results and Discussion

The object of research that is the focus of this study is the design and implementation of lighting electrical installations in simple residential houses using solar panels with a capacity of 20 Watt Peak (WP). This research focuses on the use of polycrystalline solar panels, inverter systems, batteries, and solar charge controllers (SCC) to meet the lighting needs of simple residential homes. The load used in this study is AC LED lights. Table 2, shows the tools and materials used in the research.

Table 2 summarizes the tools and materials used in this study, including a 20 WP solar panel that functions to convert solar energy into DC electricity through a photovoltaic effect, as the main component in a solar power generation system (PLTS). The 10 A Solar Charge Controller (SCC) is used to regulate battery charging, prevent overcharging and overdischarge, and optimize charging efficiency with Maximum Power Point Tracking (MPPT) technology. The energy generated by the solar panels is stored in a 12 V battery with a capacity of 7.5 Ah, which provides a power reserve when there is no sunlight, maintaining the stability of the system. The inverter functions to convert the DC electrical current stored in the battery into AC current, which is required by household electrical appliances such as LED lights. The 0.75 mm² NYAF cable is used to connect system components safely and efficiently, with low resistance to minimize energy loss. The battery cable lock plays a role in protecting the cable from physical and environmental damage, preventing short circuits, and ensuring that the connection remains secure. A 3-hole outlet is used to connect the load, making it easy for users to connect and disconnect devices from the system. The combination of these tools and materials allows the solar PV system to work effectively, efficiently, and reliably in meeting the lighting needs of simple residential houses.

3.1.Solar Panel Testing

Solar panel testing aims to evaluate the panel's performance in converting solar energy into electrical energy. The testing process was carried out over five days with the solar panel mounted perpendicular to the sky to ensure optimal sunlight absorption. The purpose of this test is to ensure that the data collected covers a wide range of weather conditions and sunlight intensity. The recorded data includes the voltage, current, and power generated by the solar panels at each time interval. In addition, routine maintenance is also carried out to maintain system efficiency, including periodic cleaning of panels to prevent dust buildup, checking cable connections to avoid power loss, and monitoring the condition of VRLA batteries to avoid damage due to overcharging or deep discharge. Fig. 5 shows the implementation of the tools used in the research.

3.1.1.First Day Testing

On the first day of testing, the solar panels are placed in the optimal location to receive sunlight. The test starts at 09.00 WIB and ends at 16.00 WIB. Voltage, current, and power data generated by solar panels are recorded on an hourly basis. The purpose of this test is to evaluate the performance of solar panels in sunny weather conditions and high intensity of sunlight. Table 3 shows the results of the first day of testing.

On the first day of testing, the solar panels were placed in the optimal location to capture sunlight, with testing taking place from 09:00 to 16:00 WIB. The data collected shows that the output from solar panels is increasing significantly over time. At the beginning of the test, at 09:00, the panel produced a voltage of 13.18 V and a current of 0.69 A. As time went by, this output increased, reaching its peak at 12:30 with a voltage of 16.94 V and a current of 1.08 A. This increase reflected the good performance of the solar panels in sunny weather conditions, where the intensity of sunlight was at its highest.

The output of the charger controller also shows a positive trend, although there is a variation in the value of the current generated. At the beginning of the test, the charger controller produced a voltage of 11.18 V and a current of 0.64 A, and increased to 14.76 V and 0.59 A at the end of the test. Although the voltage remains elevated, the decrease in current at the end of the test may be due to fluctuations in light intensity, such as moving clouds or dust sticking to the surface of the solar panel. This shows that the charger controller is able to adapt to changes in output from the panel, although the response to current fluctuations needs to be taken into account.

3.1.2.Second Day Testing

On the second day of testing, the weather conditions changed slightly, with clouds moving in the sky. The testing was carried out with the same protocol as the first day, namely from 09.00 WIB to 16.00 WIB. Voltage, current, and power data generated by solar panels are recorded on an hourly basis. The purpose of this test is to evaluate the performance of solar panels under varying weather conditions, with a decrease in the intensity of sunlight. Table 4 shows the results of the second day of testing.

On the second day of testing, weather conditions changed with the presence of clouds moving in the sky, potentially affecting the intensity of sunlight received by the solar panels. Testing is still carried out with the same protocol as on the first day, taking place from 09.00 WIB to 16.00 WIB. During this period, the voltage (V) and current (I) data generated by the solar panel as well as the output from the charger controller are recorded on an hourly basis. The purpose of these tests is to evaluate the performance of solar panels under varying weather conditions V_DC I_DC.

The test results showed that the output of the solar panels on the second day tended to be lower compared to the first day. Although at the beginning of the test, the panel's output was still the same as the previous day, which was 13.18 V with a current of 0.69 A at 09:00, the highest result of the day was recorded at 12:30 with a voltage of 15.84 V and a current of 0.95 A. This improvement shows the panel's ability to adapt, but it does not reach the same peak of performance as the first day. After that, there was a gradual decrease in output, with the final voltage recorded at 15.72 V and a current of 0.65 A at 16:00. This decrease in output could be caused by clouds blocking sunlight, which is an unexpected external factor.

The output from the charger controller shows a pattern that is in line with the output of the solar panel, although fluctuations in the current are also noticeable. The voltage of the charger controller increased over time, reaching 14.25 V at the end of the test, while the current decreased to 0.61 A. This suggests that although the charger controller can compensate for the variation in output from the panel, the significant decrease in current reflects the impact of less favorable weather conditions.

3.1.3.Day Three Testing

On the third day of the test, the weather conditions were cloudy and the intensity of sunlight was lower than the previous days. The test was carried out with the same protocol, namely from 09.00 WIB to 16.00 WIB. Voltage, current, and power data generated by solar panels are recorded on an hourly basis. The purpose of this test is to evaluate the performance of solar panels under less than ideal weather conditions, with low sunlight intensity. Table 5 shows the results of the third day of testing.

On the third day of the test, the weather conditions were cloudy with lower intensity of sunlight compared to the previous two days. The test protocol was still followed, taking place from 09.00 WIB to 16.00 WIB, where data on the voltage (V) and current (I) generated by the solar panel as well as the output from the charger controller were recorded every hour. The purpose of this test was to evaluate the performance of solar panels in less-than-ideal situations, focusing on how the system functions in the face of decreased sunlight intensity V_DC I_DC.

The test results showed that the output of the solar panels on the third day decreased significantly. At 09:00, the initial output was still the same as the previous day, which was 13.18 V with a current of 0.69 A. However, at 10:30 a.m., there was a noticeable decrease, where the voltage dropped to 12.00 V and the current became only 0.40 A. This decrease reflected the direct impact of the cloudy conditions blocking the sunlight. Although there were some hours in which the panel's output increased again, such as at 12:30 with a voltage of 15.52 V and a current of 0.94 A, overall, the output could not compete with the results of the first or second day.

The output from the charger controller shows a similar pattern to the output of the solar panel. Despite some fluctuations, the charger controller's voltage remained relatively low compared to the previous test, with the highest output reaching 14.25 V at 16:00, but the current remained at 0.61 A at the end of the test. This shows that the charger controller can function even in less favorable weather conditions, but its efficiency decreases as the light intensity decreases.

3.1.4.Fourth Day Testing

On the fourth day of testing, the weather conditions were cloudy and the intensity of sunlight was lower than the previous days. The test was carried out with the same protocol, namely from 09.00 WIB to 16.00 WIB. Voltage, current, and power data generated by solar panels are recorded on an hourly basis. The purpose of this test is to evaluate the performance of the solar panel at ideal, good weather conditions. Table 6 shows the results of the fourth day of testing.

On the fourth day of the test, the weather conditions were sunnier than on the third day, although there were fluctuations in the intensity of sunlight. The test was carried out from 09.00 WIB to 16.00 WIB by recording the voltage (V) and current (I) generated by the solar panel as well as the charger controller's output every 30 minutes. This test aims to analyze the performance of the system in favorable weather conditions but still subject to changes in the intensity of sunlight V_DC I_DC.

The test results showed that the solar panel output was experiencing a fairly stable trend with an increase in voltage and current in most of the test time. At 09:00, the initial voltage was recorded at 13.23 V with a current of 0.71 A, which was slightly higher than the previous day at the same time. The voltage and current reach their peak at 12:30 p.m. with values of 15.57 V and 0.96 A, respectively. However, as seen at 10:30 a.m., there was a significant drop with the voltage dropping to 12.05 V and the current to 0.42 A, which was most likely caused by the clouds temporarily covering the sun.

The output of the charger controller shows a pattern that is in line with the output of the solar panel, albeit with slightly lower voltage and current. The highest voltage was recorded at 16:00 at 14.30 V, while the current reached its highest value of 0.92 A at 12:30 pm. Although the charger controller's output shows fluctuations, the device is still capable of functioning properly in regulating the flow of power from the solar panel to the load.

3.1.5.Fifth Day Testing

On the fifth day of the test, the weather conditions were cloudy and the intensity of sunlight was lower than the previous days. The test was carried out with the same protocol, namely from 09.00 WIB to 16.00 WIB. Voltage, current, and power data generated by solar panels are recorded on an hourly basis. The purpose of this test is to evaluate the performance of the solar panel in less than ideal weather conditions, with ideal sunlight intensity, well. Table 7 shows the results of the fifth day of testing.

On the fifth day of testing, the weather conditions were similar to the fourth day, i.e. it was quite sunny with some periods of fluctuations in the intensity of sunlight. The test took place from 09.00 WIB to 16.00 WIB, where the voltage (V) and current (I) data generated by the solar panel and charger controller were recorded every 30 minutes. The purpose of this test is to evaluate the consistency of the system's performance under favorable weather conditions but still has variations in light intensity V_DC I_DC.

The test results show a stable performance pattern with increased output at certain hours. At 09:00, the initial voltage of the solar panel was recorded at 13.22 V with a current of 0.72 A, showing performance comparable to the results of the fourth day at the same time. The output reaches its highest value at 13:00 with a voltage of 15.50 V and a current of 0.97 A, reflecting optimal conditions when the sunlight reaches its peak intensity. However, at 10:30 a.m., there was a significant decrease with the voltage dropping to 12.05 V and the current to 0.43 A, which was caused by the possibility of a temporary disturbance such as clouds.

The charger controller's output follows a similar pattern to the output of a solar panel, with slightly lower voltage and current. The highest voltage was recorded at 16:00 at 14.29 V, while the current reached its highest value at 12:30 and 13:00 with a figure of 0.92 A. This pattern shows that the charger controller manages to efficiently regulate the power from the solar panel to the load despite fluctuations in its input.

3.2.Load Testing Using Inverters

Load testing using an inverter aims to evaluate the performance of the inverter in converting DC electric current into AC electric current and supplying power to the load (3watt LED light) with a wide range of lights. Testing is carried out to ensure that the inverter can produce stable output voltage and frequency, as well as being able to handle varied loads. The test started with one light, continued with two lights, and finally three lights. The data collected includes the voltage, current, and power generated by the inverter, as well as the performance of the LED lamp as a load. Table 8 features load testing using one 3-watt LED light, Table 9 uses two 3-watt LED lights, and Table 10 uses three 3-watt LED lights.

In a single lamp test (Table 8), the inverter was able to convert DC current to AC well, despite a gradual decrease in input voltage from 14.4 V at 09:00 to 13.67 V at 16:00. The output voltage of the inverter remains stable in the range of 222-223 V, with a constant output current in the range of 0.1 A. This indicates that the inverter can maintain the quality of the output despite the decrease in input voltage in line with time.

In the two-lamp test (Table 9), there was an increase in load, which was reflected in the increase in the input current of the inverter to be in the range of 0.43 A to 0.48 A. The input voltage of the inverter also decreased in a similar way to the single-lamp test, but the inverter managed to maintain a stable output voltage in the range of 222-223 V. The output current of the inverter was slightly higher than that of the single-lamp test, i.e. 0.18 A to 0.19 A, which reflects an increase in load on the two operated LED lights. These results show that the inverter can handle larger loads well.

In the three-lamp test (Table 10), the load pulled by the inverter increased, which can be seen from the increase in the input current of the inverter to be constant at 0.75 A throughout the test. The input voltage of the inverter decreases more significantly, from 14.4 V at 09:00 to 12 V at 16:00. However, the inverter can still keep the output voltage stable in the range of 222-223 V. The output current of the inverter is also higher, which is 0.28 A, which reflects the power required by the three operated LED lights. Despite the drop in input voltage, the inverter can still supply enough power for three lights with stable performance.

Overall, the test results show that the inverter can handle increasingly large loads well, whether on one, two, or three LED lights. Despite the decrease in input voltage over time, the inverter is still able to produce a stable output and meet the power needs for LED lights. This shows that the inverter has a good performance in converting DC energy into AC with reliable output quality, and is able to handle fluctuations in input voltage without sacrificing the output stability required for the load.

The solar panel power test was carried out for five consecutive days with power recording (W) every 30 minutes from 09:00 to 16:00 WIB (Table 11). This analysis aims to compare the performance of solar panels in varying weather conditions as well as observe the trend of energy output produced.

The test results showed that the average power of the solar panels on the first day reached 12,305 W, making it the best performing day compared to the other four days. On the second day, the average power dropped to 11,703 W, although the total amount of power remained quite high, namely 87,772 W. A significant decrease occurred on the third day, with the average power only reaching 10,376 W and the total amount of 77,820 W. This was due to cloudy weather conditions that reduced the intensity of sunlight.

The fourth and fifth days showed relatively similar results, with average power of 10,765 W and 10,764 W, respectively, and total power of 80,738 W and 80,734 W. On both days, although the weather conditions were clearer than the third day, fluctuations in light intensity still affected the performance of the solar panels, especially at 10:30 to 11:30 am, when the power was in the range of 5-6 W due to possible sun interference.

The highest peak power occurred at 12:30 p.m. on the first day, with a value of 18,295 W. In contrast, the lowest power was recorded at 10:30 a.m. on the third day, which was 4,800 W. This trend suggests that the optimal intensity of sunlight at a given time greatly affects the performance of solar panels.

Testing of the output power from the SCC entering the battery was carried out for five consecutive days to evaluate the efficiency of energy transfer from the solar panel to the battery. Power data is recorded periodically every 30 minutes from 09:00 to 16:00 WIB, with the aim of identifying power distribution patterns and the influence of weather conditions variations on the performance of the charging system. Table 12 shows the test power of the SCC data output to the battery.

The solar charge controller (SCC) output power test for five consecutive days aims to measure the efficiency of energy transfer from the solar panel to the battery under various weather conditions. Power data is recorded every 30 minutes from 09:00 to 16:00 WIB. This analysis compares the average power, total power, and change trends of SCC output on each test day.

The test results showed that the highest average power of SCC was recorded on the second day, which was 9,413 W, with a total power of 70,596 W. The first day recorded a slightly lower average power, which was 9,351 W, with a total power of 70,130 W. Both days showed optimal system performance, with stable power output at various test times.

On the third day, the average power dropped to 8,554 W, with a total power of 64,156 W. This decline was due to cloudy weather conditions, as seen at 10:30 when the power dropped to 4,725 W, which was the lowest value among all the data. The fourth and fifth days showed similar performance, with average power of 8,893 W and 8,891 W respectively and total power of 66,695 W and 66,685 W, respectively.

The highest peak power occurred at 12:30 p.m. on the first and second days, at 13,040 W, respectively, reflecting optimal sunlight intensity conditions. In contrast, the lowest power value on all test days was recorded at 10:30 a.m. on the third day, which was 4,725 W.

4.Conclusion

Based on the results of research and evaluation, it can be concluded that lighting electrical installations using 20 WP solar panels are able to meet the energy needs of simple residential houses with main components such as polycrystalline solar modules, VRLA batteries, charge controllers, and AC lamp loads. The performance of the system is greatly affected by weather conditions, where sunny weather produces optimal output with a peak voltage of 16.94 V and a current of 1.08 A, while cloudy weather causes a significant drop to a minimum voltage of 12.00 V and a current of 0.40 A. Nonetheless, the charger controller shows adequate stability in the face of weather changes, with the final voltage ranging from 14.30 V to 14.76 V. Therefore, Weather factors have a direct impact on the energy conversion efficiency of solar panels. To maintain optimal system performance, regular maintenance such as panel cleaning, cable connection checks, and monitoring of VRLA battery condition is essential. Implementing a consistent maintenance schedule will help reduce the risk of damage as well as ensure that the solar panel system remains operational efficiently and reliably in the long term. Thus, proper design and maintenance are key to the successful use of solar panels as an alternative energy source.

Supplementary Materials: No supplementary materials are available for this article.

Author Contribution: All authors contributed equally to this paper. All authors read and approved the final version.

Funding: This research did not receive any external funding.

Conflicts of Interest: The authors declare no conflicts of interest.

References