Project Report On Construction Of 200W, 24v Moncrystalline Solar Panel


                         CHAPTER 1

World energy consumption has been increasing rapidly almost exponentially due to the industrial revolution. This increasing trend of energy consumption has been accelerated by improvement in the quality of life. At present, most of the energy required is met by the combustion of fossils fuels (i.e. coal, petroleum oil, natural gas, etc) which have become an essential and integral part of modern civilization, being increasingly relied upon since the industrial revolution. Only a very small proportion of the energy comes from nuclear and hydro, geothermal, tidal wave, and so on. This almost exclusive reliance on the combustion of fossil fuels has resulted in enormous amounts of harmful pollutant (CO2, SO2, and NO2)
Emissions to the environment, has caused severe degradation of the local and global environment and has exposed the world population (from human to animals and from plants to all forms of life on earth) to the hazards.
Under these circumstances, interest in mono-crystalline solar cells provide clean energy source because the solar energy is directly converted into electrical energy without emitting carbon dioxide. The solar energy is not limited, free of charge and distributed uniformly to all human beings. Solar cell has shown that it can generate electricity for the human race for a wide range of application, scales, climates and geographically locations.
Mono-crystalline is safe for the environment and one of the most abundant resources on earth, representing 26% of crustal material. Among the crystalline silicon solar cells, mono-crystalline silicon technique is used as a promising method for solar cell fabrication due to its high efficiency.


In our country today interrupted power supply has been a serious issue and it makes life difficult and unbearable because firms, industry, churches, shopping malls, schools and even business centers etc, depends on power supply for their day to day running activities. However, some have resulted to plant and generators to enable them meet up. But these machines, with their emission of gasses to the atmosphere pose health challenges. If constant electricity must be assured, all the setbacks would be forestalled. This is exactly what this project intends to proffer solution to.

The aim of this project is to fabricate a standard 150watt, 12volt mono-crystalline solar panel, and this will be achieved with the following objectives:
To achieve higher efficiency rate of electricity since they are made of the high grade silicon.
To provide a solar panel that will last much longer.
To provide a solar panel that will be more efficient in warm weather.
To implement a solar panel that is more reliable.
The significance of this project work cannot be over emphasized. This is because of the problem of fossils fuel damage it has cost to the global warming which the earth as already seen the unfriendly impact of an unnatural weather change due to global warming. The mono crystalline solar panel is useful in many ways. It captures energy from sun and turns it into electricity. Because the cell is composed of a single crystal, the electrons that generate a flow of electricity have more room to move.  As a result, a mono crystalline panel are efficient than its counterpart. Most significantly, the solar panel serves as an alternative source of electrical power supply which is needed in our society.

This project follows ‘cradle to gate’ approach. A life cycle inventory of a photovoltaic power plant with a 150watts peak capacity is built up. The scope and system boundary are described below:

Figure1.1: Block Diagram of a Mono-crystalline PV Solar Panel Module
This project is designed for a150watts, 18volts solar panel. It is arranged in three units, matrix unit, configuration unit and reverse protection unit.
Matrix unit is the arrangement of the solar cells in series.
Configuration unit is soldering of the different cells together with the aid of tabbing wire and the reverse protection unit is the inclusion of diode to avoid charges returning back to the solar panel when there are no longer charges on the solar panel at night.                                   

1.7 Report Layout
This report is made up of six chapters, chapter one being the introductory part of the project as represented below; This gives an introduction to the general concept of power, the significances and objectives which the project report seek to achieve. It also explains the scope of the project and problem statement.

Chapter 2: Literature Review
It gives the historical and theoretical background of the project, a study of the previous methods used and a critical analysis of the new approach and its significance in comparison with previous method.

Chapter 3: Materials and Methods
This gives the technical description of the components used in assembling, including the reasons behind their choice. It also gives the details of the methods used in realizing the project, which includes both the research methods and circuit architecture.

Chapter 4: Design Analysis and construction 
In this chapter, the step by step approach in determining the values of the circuit components based on the project goals are clearly given. It also gives details of the procedure followed in implementing the realized circuit diagram on the circuit board and packaged of the device.
Chapter 5: Test Result Analysis and Discussion 
After implementing the circuit, various tests were carried out on different blocks of general block diagram to verify the block design specifications. Those results are presented and discussed in this chapter.

Chapter 6: Conclusion and Recommendations

The final achievement in this project, including the knowledge acquired, is stated in this chapter. A set of recommendation are also made as it concerns areas requiring possible improvement and usability of the final products.

                     CHAPTER 2
Photovoltaic effect is emergence of electric voltage in a system exposed to solar radiation. With absorption of photons, charge carriers are excited into conduction band. The mechanism of light induced electron transition to higher energy state is similar to the photoelectric effect; where a photoelectric was explain by Albert Einstein in 1905. Converting solar radiation into electrical energy is called photovoltaic (PV). Devices exploiting PV effect are called solar cells, also photovoltaic cells or photovoltaic devices.
Edmond Bacquerel (1839), born in Paris; discovered that when two electrodes were placed in an Electrolyte, a voltage develops when sun light falls upon the electrolyte; this gives the basic principle of solar power. Other Authors threw more light on the solar panel system.
Daryl Chapio et al (1954) of bells labs are credited with the world’s first photovoltaic cells (Solar cells). In other words, these are the men that made the first devices that converted sunlight into electrical power. The three Scientist joined Forces and presented their solar battery powering a small toy windmill and a radio at efficiency of 6%. The key to their success achievement was the ability to diffuse boron into silicon in a process known as “Doping”. 

Hundreds of solar cells (also called photo-voltaic cells) make up a photovoltaic (PV) array.  Solar panels are the components of solar arrays that converts radiates light from the sun into Electricity that is then used to power electrical devices, Heat and cool homes and Businesses. Solar cells contain materials with semiconducting properties in which their electrons become excited and turn into an electrical current when struck by sunlight.

Dr. Bruno Lange (1931), a German scientist predicted that, in the not distant future, huge plants will employ thousands of these plates to transform sunlight into electric power…that can compete with hydroelectric and steam-driven generators in running factories and lightning homes. But Lange’s solar batteries worked no better than Fritz’s, converting far less than 1% of all incoming sunlight into electricity-hardly enough to justify its use as a power source.
University of Delaware (1972) developed a photovoltaic research in their laboratories which culminated to one of the world’s first PV powered house
“Solar cell”. Using the model known today as “the solar feed-in” surplus electricity generated during the day is fed back into the grid.

While there are dozens of variations of solar cells, the two must common types are those made of crystalline silicon (both Mono-crystalline and Poly-crystalline) and those made with what is called Thin film Technology.
Gerald Pearson (1954) of Bells Lab developed the mono crystalline solar cells also called “single crystalline” cells are easily recognizable by their color. They are made out of what are called “silicon ingots”, a cylindrically shaped design that helps optimize performance in the silicon world, the more pure the alignment of the molecules, the more efficient the materials is at converting sunlight into electricity, which is an attribute of a mono-crystalline solar cells of which its efficiency has been documented at upward of 20%. Essentially, designers cut four sides out of cylindrical ingots to make the silicon wafers that make up the mono crystalline panels. 
Beyond being most efficient in their output of electrical power, Mono-crystalline solar cells are also the most space efficient. This is logical since you would use fewer cells per unit of electrical output. In this way, the solar arrays made up of mono-crystalline take up the least amount of space relative to their generation intensity. Another significant advantage is that they also last the longest of all types. Many manufacturers offer warranties of up to 25 years on this type of PV system. 

The Polycrystalline Solar cells 
Calvin Fuller (1981) of Bells Lab discovered the Polycrystalline solar cells also known as poly silicon and multi silicon cells were the first solar cells ever introduced to the industry, in 1981. Made from cast square ingots large blocks of molten silicon carefully cooled and solidified. They consist of small crystals given the materials it’s typical “metal flake effect”.
However, polycrystalline is less efficient than its Mono-crystalline solar PV system operated at a 13-16% efficiency again this is due to the fact that the material has a lower purity. Due to this reality, polycrystalline is less space-efficient, as well. One other drawback of polycrystalline is that it has a lower heat tolerance than Mono-crystalline, which means they don’t perform as efficiently in high temperatures.
Karl Boar (1972) established the institute of energy conversion (IEC); located at the University of Delaware this was established to pioneer research on thin film solar cells.  This is made by depositing one or more thin layers or thin film (TF) of photovoltaic material on sub straight such as glass, plastic or metal. The thin film Cells are said to be flexible and lower in weight. Thin Film Technology has always been cheaper and the lab cell efficiency for CBTE and CIGS is now beyond 21%, outperforming Multi-crystalline, the dominant currently used in most solar PV system
Dye-sensitized solar cells 
Brian O’ Regan and Michael Gratzel ( 1988) were the co inventors of the modern version of a Dye solar cells popular known as the Gratzel Cells a dye sensitized (DSSC,  DSC, DYSC or Gratzel Cell) is a low cost solar cell belonging to the group of thin film solar Cells. It is based on a semiconductor form between photo-sensitized anodes an electrolyte, a photo-electrochemical system. DSSC has a number of attractive features; it is simple to make using conventional row-printing techniques, its semi-flexible and semi-transparent which offers a variety of uses not applicable to glass-based systems, and most of the material used are low cost.
The solar window 
Derek Markhan (2012), suggest that  Solar window modules are created by applying ultra-thin layers of liquid coatings produce ultra-small solar cells and form groups called ‘arrays’. Because of the family of material that is being used and the architectural design pattern, the final product is generally referred to as an organic photovoltaic solar array (OPV). The coating of these solar windows produces world’s smallest functional cells, (measure less than ¼ the size of a grain of rice) and can be applied at room temperature.  

The Mono-crystalline being the first variety of solar panel as compared to other solar panels, converts the most amount of solar energy into electricity. This is also the most preferred choice because it poses no threat to the environment unlike some solar films which uses cadmium telluride which is not environment friendly. Furthermore, its high efficiency of about 26.7% cannot be sidelined, because its yield more power output with that regard compared to other solar cells. The third generation of solar cells includes a number of thin film technologies often described as emerging photovoltaic most of above have not been commercially applied and are still in the research invested into these technologies as they promise to achieve the goal of producing low cost, high efficiency solar cells.

We do not yet have enough manufacturing capacity for solar panels.
The radiation of sun is nearly fixed; the place that could be used to pave solar panel is limited.
We cannot exploit all of sunlight to electricity because biosphere needs it.
We do not yet have enough storage at low enough cost for load balancing; its output is intermittent, needs grid, battery or other buffering system to work together in large quantities.
They are a great deal of bogus political and financial resistance to solar and other renewable spearheaded by those who stand to lose trillions of dollars when fossil fuels loose nearly all market values.  


It often beats the imagination how mere sunlight (solar power) can be used to generate electricity. Solar power generates electricity by converting solar energy through the principle known as photovoltaic principle (the process between radiation absorbed and the electricity induced).
A number of solar cells are electricity connected to each other structure or frame called the photovoltaic module. The module is arranged in series to form the array. Generally speaking, the greater the area of the array, the more electricity it can produce.
                               CHAPTER 3
                MATERIALS AND METHOD
For this project work, the following parameters were considered:
Load estimation of the building, system component of the solar panel which comprises of the pegboard assembly, solar cell assembly installed PV system, final testing for full voltage/ current operations
For this project work, 0.15KVA (150 watt) is the estimated load of the facilities (project wok). The below analysis gives a breakdown of the component used in this project.
Mono crystalline solar cell
Pegboard (backing board)
Tabbing/bus wire
Silicone sealant
UV-protection sealant
Flux pen
MC4 connectors

To make solar cell from Mono-crystalline solar panels, silicon is formed into bars and cut into wafers. These types of panels are called “Mono-crystalline” to indicate that the silicon used is single-crystal 

Figure 3.1: Diagram Mono-crystalline solar cell

Usually referred to as solar spacers, this is designed to assist solar PV module installations. This ‘spacer’ allow us to achieve a consistent pattern and maintain uniformity in the solar panels. Furthermore, it helps ensures that all the panels used are laid equidistance from each other, providing symmetrical and professional finish.  

Figure 3.2 Diagram of spacer

The pegboard, also known as the backing board is perforated thin bard made out of non-conductive materials such as wood, plastic or glass. For cost effective propose wood is being used in this project work. This backing board is being drilled with evenly spaced holes which enables a free passage of the cells wire.

Figure 3.3: Diagram of pegboard

A tab wire is used to connect a solar cell in series to get the require voltage needed. The solar cells were connected in rows (series) making sure the wire is around 18:20mm thick to carry the current better. 
The tabbing wire is made out of solid copper coated with solder for easy flow which required the use of solder when connecting cells together. The burst wire looks like a tab wire but is much wider. The burst wire is used to carry the current across each row. It ranges from 2.5mm-5mm which depends on the power of the panel and size of the solar cell that is being used.

Fig 3.4 Diagram of a tabbing/ bus wire

The above process involves the interconnections of cell to cell which form a module and also the interconnection of modules which forms an array. Some distinct processes involved for the above to be completed are: drilling and soldering, painting of the box, wiring the panel, attaching of Plexiglas using the appropriate screws and drill.
Drilling and soldering: the backing board is being drilled with respect to the position of the solar cells wire and soldering done to the bus wire by connecting some connectors alongside.
Painting of the box: this process keeps the box cooler which helps the cell to perform better when they are cool. One major advantage is that it helps the panel to last longer.

Plexiglas panels are made of acrylic material which means that they can be easily cut with a hand saw. Plexiglas allows 90 percent of light rays to pass through it to the solar cells. Despite allowing this much light through to the solar cells, Plexiglas protects the solar cells very well from wear, ensuring that they last as long as possible.

Figure 3.5 Diagram of a Plexiglas

(SN-502 all weather) –low modulus: SN-502 all weather sealant-LM is a one part, construction grade, low modulus, RTV Natural silicon sealant. It is suitable for a wide range of sealing and glazing applications were durability and reliability is required, it has a superior resistant to UV-Radiation, vibration and weathering etc. 
It adheres to a variety of non-porous substrates such as glass, ceramics, tiles, aluminum, plywood and composite panels etc. 

Figure 3.6: Diagram of a silicone sealant

This is used to protect the solar cells from high heat and it is also used for the purpose of long lasting protection 

Figure 3.7: Diagram of a UV-protection sealant
They are single-contact electrical connectors commonly used for connecting solar panels. The MC in MC4 stands for the manufacturer multi-contact and the 4 for the 4mm diameter contact pin.
 MC4s allows strings of panels to be easily constructed by pushing the connectors from adjacent panels together by hand, but require a tool to disconnect them to ensure they do not accidentally disconnect when the cables are pulled. The MC4 and the compactable product are universal in the solar market today, equipping all solar panels produce since about 2011 which allow longer strings to be created.

Figure 3.8: Diagram of a MC4 connector

 3.2.0 FLUX PENS
 These are small plastic containers with a spring loaded felt tip at one end with a slight amount of pressure, the tip allow flux to wick through the felt and onto the cell. 

Figure 3.9: Diagram of a flux pen
Procedures for the construction of solar panel used in this project are given below; Dimension of solar cell = 6inches by 6inches (0.24mm by 0.24mm). The solar panel construction was done in two stages:
Stage one: Tapping of the solar cells and 
Stage two: Cutting of solar panel frame

Table 3.1: Tapping of Solar cell

Working Principle of the Solar Panel (Cells Connection)
This project research operates on the principle of Photovoltaic effect. This is a process that converts sunlight (solar energy) to direct current electricity. For this to take place, the solar panels have to be placed where adequate photons can incident on it is usually placed at roof-tops. When sunlight is incident on the solar cells on the solar panels, electrons are knocked loose from the solar cells until a higher energy level is reached whereby the electrons flow away through to an external circuit. 
The physics behind this is that solar cells are made of two semi-conductors joint together to form p-n junction. The p-type semi-conductors have a high concentration of holes, while the n-type has a high concentration of electrons. This joining enables excess electron from the n-type to diffuse with the hole of the p-type. 
This movement of this excess electron to the p-type exposes positive ion at the n-type while the movement of holes to the n-type exposes negative ion on the p-type resulting in an electron field at the junction forming the depletion region. Under such circuit condition, the charge carrier exit (leaves) the solar panel as light generating current.
Cells can be connected in either series or parallel connection. Series connections consist of cells connected end to end. When cells are connected in series, their voltages add but their currents do not. The current of a series connection is same as one cell; which is what is used in this project by connecting the positive of the first solar cell with the negative cell of the second solar cell, then negative of the second with the positive of the third solar cell and so on. Parallel connection consists of cells connected side by side. When cells are connected in parallel, their currents add, but their voltage does not. This is achieved by connecting the positive of the first solar cell to the positive of the second solar cell then the positive of the second to the positive of the third solar cell. Connection of the two types can obtain nearly any combination of voltages and current resulting in a wide variety range of output power ratings.

Circuit diagram:


Figure 3.11: circuit diagram for a series connection of a mono-crystalline solar panel
Since a solar cell only generates about 1 to 2watts of power, it is necessary to combine them into solar power panels in other to generate more power. Photovoltaic modules commonly called solar modules are the key components used to convert sunlight into electricity. Solar modules are made up of semiconductors that are very similar to those used to create integrate circuits for electric equipment. The most common type of semiconductor in use which is also used for this project is made of silicon crystal. The electricity produced is called direct current (DC) which charges a battery and when an inverter is being added, it converts this DC voltage to AC voltage needed directly for a useful work (though not part of this project report).
During the course of this project work, that is, seeking for information on how a 250w PV solar panel can be assembled with more efficiency. This project led us to the internet site where we browsed and sort for materials throughout the course of this project, and also other information centers such as the Polytechnic Library, project books and oral interview with my project supervisor, technologist and other Electrical Engineers.


This chapter explains each stage of the material seen in chapter (3), which deals with gathering of various materials for each stage. The circuit diagram was used to assemble the solar cells on a pegboard (which is light-weighted) the purpose of the light weighted pegboard used was for easy carriage and mounting. Since the project work deals with the assemblage of a PV solar panel, the various steps or procedures on how this was achieved would be discussed under this chapter which includes;
Cutting of the pegboard and putting frames together 
Creating of holes on the pegboard for connection
Assembling the solar cells 
Gluing the solar cells down 
Soldering Bus wire and the tabbing wire 
Fixing of the Plexiglas into its frame 

This is the chosen surface at which the solar cells are being mounted upon. The pegboard was cut into size with a Formica of the same dimension was also cut and attached on the pegboard using an egoistic gum.
 This platform brings out the uniqueness of the solar panel after the cells were mounted on it. The size/dimension of the pegboard was a factor of the number of solar cells needed for the aluminum was also cut with regards to the dimension of the pegboard and holes made for screwing of the Plexiglas to it.

With the pegboard now coated with Formica a single solar cell was placed on it inside the frame to get an idea of the dimension needed for the holes to be punched around the board and then taking the solar cells back out once the measurement was made. Drilling holes across board was then very easy with this idea. Furthermore, we drilled two holes at the head of the frame for the negative and positive connections to run out.

Being the main work of this project, assembling of the solar cells was carefully done due to its fragile nature. Taking into consideration its negative and positive part, that is, its positive part being placed on the pegboard and its negative part facing up with regards to the holes created; the solar cells were connected in series with a total of 36 cells using a tabbing wire and a soldering iron to connect the solar cells together. We then glued each solar cell to the coated pegboard using a silicon sealant.


For this panel we have four (4) strings of solar cells. To connect this string of solar cells, we used a bus wire. This bus wire goes at the end of the string to create one long string. Next after hooking all 4 strings of solar cells up in series, we got 22 gauge bus wires ready for soldering. This was hence linked to the tabbing wires at the sides of the solar cells which were hence drawn to the output.

The Plexiglas is a very important material used during the assembling of solar cells to form a module. Being a preferred material for constructing solar panels compared to the tempered glass, its holds up better in harsh weather conditions and is more shatter resistance while still allowing 90% of light to pass through it to the solar cells. The Plexiglas (Acrylic sheeting) was to protect the solar cells from excess dust which would certainly decrease the life span of solar panel.
Specification of the Solar Panel
Solar panel voltage ---------------------------------18v
Solar cell efficient ----------------------------------14.85%
Cell Type --------------------------------------------Mono-crystalline 
Frame used ------------------------------------------Aluminum 
Standard Test Condition (STC) ------------------1000w/m2
Maximum open circuit voltage (Voc) ----------18.89v
Minimum voltage at open circuit ------------------16.56v
Glass used ---------------------------------------------Plexiglas 
Voltage per cell --------------------------------------0.5v 
Number of cells --------------------------------------36 cells connected in series 
Each cell produces a current of --------------------0.143amps
Total current produced -------------------------------4.453amps
Expected Life span of the solar panel -------------------------10 years
The two terminal (red and black) of the output was gotten by the connection of  each cell in series using a bus wire and hence connecting it to the tabbing wire through which the changes that is electrons and holes from the negative and positive sides of the cells respectively passes through to the output. This was tested at both high intensity of sunlight and low intensity using a multi meter to get its open circuit voltage at maximum and open circuit voltage at minimum

                        CHAPTER 5

The testing of each cell that makes up the circuit was carried out effectively to ensure its working condition so as to produce a desired output with regards to the series connection pattern adopted in this project work. 

Knowing full well that the connection pattern used in this project work was to increase the system (panel’s) voltage, hence the testing of the solar panel for volts started by testing each of the solar cell connected in series and the overall output voltage or open circuit voltage of the solar panel. The below procedure was taken through the connection made by the multi meter to the solar panel’s output 
To test solar panel voltage output, we put the solar panel in the multi-meter  direct sunlight, and set the multi meter to “volts” setting 
We touched the multi-meter (red) positive lead to our solar panel’s positive wire
We hence touched the multi-meter (black) negative lead to our solar panel’s positive wire 

With regards to the series connection, each cell gave a voltage of 0.5volts mathematically speaking its total output voltage will give 18volts. At maximum intensity of sunlight using a digital multi meter as the measuring instrument, its maximum output voltage rose up to 18.89volts. 
With regards to the above procedure, the aforementioned maximum output voltage was observed.


It is a known fact that the current generated by the solar panel is Direct Current (DC); hence to get the total current produce by each cell and the total current produced by each cell and the total current produced by the total series connected solar cells the below procedure was followed 
To test solar panel amperage output, we paced the solar panel under the sun with high intensity, setting the multi-meter to the “amps” setting.
We touched the meter’s (red) positive  lead to the solar panel positive wire 
We hence touched the meter’s (black) negative lead to the solar panel’s negative wire 


The amp reading in the meter gave a reading of 3.5 amps at maximum sunlight intensity. Hence for each solar cell used in the assemblage of this work it is certain that it produces a 0.143amps with regards to it rated voltage of 0.5v and 3.45amps series connected solar cell.
The power rating of each cell was being imprinted by the manufacturer. That means that the power rating of cell varies in prices. The one used for this project work is rated 6.8 watts for each solar cell.
With regards to the aforementioned voltage per cell, the total power rating mathematically speaking gave a 150watts which is the total power rating of the solar panel.
Measuring the amount of sunlight that solar panel systems are able to convert in actual electricity is the performance parameter. The outcome determines solar panel efficiency and it’s always measured in percentages.

This can be described as a measure of how reliable the project work can be at different intensity of sunlight incident on the solar panel. It can be seen below that the degree of sun ray on the panel is a prerequisite of its output at different test type or condition.   
Table 5.1 Reliability Measurement 






This section of the project report forms the concluding part of the project report and takes a look at some of the problems encountered during the progressive assemblage of the system and also brings in suggestion for further improvement and/or enhancement of the solar panel or system assemblage.
The sun is a powerful  source of energy that helps our planet by giving us clean reusable energy to power the society the use of this energy is free does not create pollution and when used widely can help us become less dependent on other costly and damaging forms of power supply.
The assemblage of the solar cell to form the solar panel module has given us a wattage of 150watts which is lower compared to the specification given by the school project coordinators’ team this was due to the following reasons.
Due to the fragile nature of the solar cells which so many were broken at the course of assemblage as a result of low level of capability in handling of the cells while assemblage for module 
Another shortcoming has been seen in the total output wattage which is giving 150watts instead of the proposed 200watts specification.

 This was as a result of the expensive nature of the cells with higher wattage manufactures specification specifications.

This project is viable for offices both private and public, schools, hospitals and even living houses. This helps conserve energy and reduce the expenses on electricity bills and other expenses that goes with lighting. 
In consideration of its functionality and to enhance its performance characteristics; thus, after the completion of this project work, the following would be necessary so as to achieve high output efficiency. 
Solar cells at low cost of high wattage should be made easily available for purchase
 Further research should be made on the reduction in size of this solar cells with an improve efficiency of the cells.
The solar panel module should be maintained regularly by cleaning its surface and removing of debris so as to have maximum sunlight penetration on the cells.

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