How Do Solar Photovoltaic Cells Work? The Step-by-Step Process Explained

Introduction

In a world that is swiftly moving towards cleaner energy, solar photovoltaic cells have become the ultimate heart of modern-day power generation. These small units are the ultimate reason that sunlight can be turned into usable electricity today. Since the need for efficient and renewable systems has been arising, it is essential to understand how do solar photovoltaic cells work, keeping in view the customers and professionals. From rooftop systems to industrial-scale installations, their role continues to expand globally. This article aims to discuss how the cell functions, explain some of its components, and why they are important for the future of sustainable power.

What Are Photovoltaic Cells? Explained Simply

A photovoltaic cell or PV system is a semiconductor device that easily converts light to electrical energy. The word photo-voltaic combines both photo, which means light, and voltaic, which means electricity. The solar electric cells are sometimes referred to as solar cells, photovoltaic cells, or P.V cells. These cells are the basic building blocks to form a solar panel. A single cell can only supply electricity.

Hence, if connected in an organized manner in series or encapsulated into a panel, it will be able to provide enough amount of electricity. Photovoltaic cell is simplified in this context as cell that converts or heats the energy to electricity.

Each single cell is created with silicon to form a semiconductor. Silicon is chosen as a preferred material because it can provide efficient movement of electrons from one atom to another, and it is easily available. The silicon used should be very pure and come in two types, known as p-type and n-type. A thin layer of p-type silicon is supplied with both P-N junctions and N-P-N layers to create a field of electricity. This type of cell also produces electricity by applying direct current.

And that’s all about a Photovoltaic cell definition that can support or generate electrical power or electricity. Sometimes these cells are used remotely to power backup systems and remote monitoring stations.

Structure of a Solar PV Cell: Layers & Components

The solar photovoltaic cell may seem pretty simple from the outside, but it is a designed structure with several layers made up of different components that work together to convert light into electricity. Each of them has a specific role to play.

It is like a high-tech sandwich. The top layer is a cover of glass over the main part of the cell. The glass is used to protect the cell from dust, moisture, and any impact. The layer right below the top layer is an anti-reflective coating. The task of the coating is to allow as many sun rays to enter the cell and not reflect aside. Below the anti-reflective coating, the front contact is present. The front contact is used to collect and then conduct the electricity formed in the cell.

The main part of the cell is the silicon PV cell. An n-type silicon is present on the top of the PV cell, whereas the p-type silicon is the bottom layer. The n-type silicon layer is rich in electrons, and the p-type silicon layer is rich in holes, also known as positive charges. So, when both types of silicon are on the same cell, it forms a p-n junction. Which is important to form an internal electric field in the cell, due to which there is a current flow. The last visible layer is the back contact.

Understanding these layers of a solar cell is very important to understand how photovoltaic panels are made and work, and which layer performs what function to provide long-term, cleaner, and reusable energy.

The Photovoltaic Effect: How Electricity is Created from Sunlight

The generation of electricity from sunlight is called the photovoltaic effect. The rays are converted into electricity in the absence of any moving items or combustion.

The basic process of photovoltaic plates working is when sun rays fall on the cell, particles of the light called photons fall on the top silicon layer. Every photon is vested with energy. If the energy of the photons striking the silicon is more than the minimum energy required for knocking the electron out of it, then it becomes excited, and it is separated from the atom.

During the period of time when the electron is in this decided state, it moves from p-type towards the n-type side of the p-n junction. When an electron moves from one side to the other of a p-n junction, a charge is created, which creates an electric field. Because of the built-in electric field, the freed electron is pushed in one direction— inside a circuit.

Then the structure of the silicon cell forces the excited electron to move in one particular direction, thus creating a direct current (DC). The current then flows from the cell through an electrical circuit, giving electrical power to electrical devices.

The excited electron keeps moving through the circuit until it reaches the back contact, from where it can fill up the hole and thus is in the initial step. Thus, the process from the separation of the electron up to the rejoining of the electron with the hole in the molecule of the silicon develops a voltage difference of approximately 0.5 to 0.7 volts between the two layers or ends of the solar panel.

To increase the amount of electricity generated, solar photovoltaic plates are kept in the sun. This electrical energy generated doesn’t make any sound and doesn’t have any polluting by-products.

So here we get to know How Do Solar Photovoltaic Panels Work with the help of the photovoltaic effect, and how they are a great source of energy, which works silently and produces no pollution and is a renewable source of energy.

Step-By-Step: How Do Solar Photovoltaic Panels Work?

To know how do solar photovoltaic panels work, it’s important to know them as units and not a single panel. A standard HBOWA panel has about 60-72 solar photovoltaic cells in series with each other. These cells together produce more power than a single cell.

When the sun strikes the panel, each cell produces direct current. Every DC power thereafter flows through a conductive wire to an inverter from a reputable brand such as HBOWA. HBOWA inverter then converts that current to alternating current, which is then used by electrical appliances in residential, commercial, and industrial sectors.

The panels are set up in a series of rows. These rows gather power and send it to an electrical panel or battery system, depending on the use. The whole working process is hassle-free and automatic. Photovoltaic and solar cells work as long as there is sunlight after being installed.

For instance, there is a public school. One day, the school authorities decide to install a rooftop solar panel array. The power of the solar panel array is connected to the classrooms. Throughout the day, those arrays power classroom lights, fans, projectors, and more, therefore reducing the electricity bills and the carbon footprint of the school.

This is the basic PV panel working flow:

Different Types of Solar Photovoltaic Cells

Several kinds of photovoltaic cells are made of different materials and serve different purposes. The variation in these cells causes different efficiency, longevity, and costs, and needs to be determined to determine the types of solar panels one could use. Monocrystalline photovoltaic cells contain only one silicon crystal with high purity.

Monocrystalline cells are highly efficient and work well even in the low light. This makes these panels perfect for houses with massive roofs, but not for small homes and rooftops. Often, the costliest option of the solar panels. Polycrystalline, also known as multicrystalline cells, are made by melting together a lot of silicon pieces. These work only slightly less efficiently than the Monocrystalline and have similar features, but are also a lot cheaper and relatively used in larger scale installations.

PERC stands for Passivated Emitter and Rear Contact cells, where monocrystalline photovoltaic cells are further added with a passivation layer. This way, the light and the electrons get effectively absorbed and flown. There are many reputable suppliers of new tier 1 solar panels, discount solar panels, and used solar panels, such as HBOWA. HBOWA provides the latest solar technology at the best price and provides the best warranty programs for the solar kits they provide.

Here’s a comparison of those cell types:

Each pv cell technology has trade-offs. HBOWA’s focus on PERC makes it suitable for clients’ needs.

Case Study: Commercial Use of HBOWA PERC PV Panels

A renowned logistics warehouse located in the southeast part of Asia started using HBOWA’s PERC panels for commercial use with a motive to reduce their high operating cost and to enhance the reliability of power. The energy demand of the site was very high on a daily basis, as its refrigeration unit, warehouse lights, and servers are on around the clock. Before the switch to solar panels, the high instability of the grid in the area had caused delays of several hours due to the malfunctioning of machines and the general wear and tear of the equipment.

So, to counter this problem, the PERC panels were installed and allowed the warehouse to obtain a consistent flow of power throughout the day, with a significant reduction in the requirement of grid power during the high peak hours. A commercial-scale solar system was set up to ensure the delivery of a constant supply of power during the day and to charge the HBOWA’s battery banks with the surplus power during the peak hours.

As a result of the solar power system, the warehouse was able to reduce its electricity bills by 30% in the first year, along with a significant reduction in the malfunctioning and stopping of the regular operations at the warehouse; that is, the returns are speculated to be within 5 years.

The energy flow that aids the purpose is as follows: sunlight is absorbed by the HBOWA’s PERC panels and converted it into DC power. The system also has HBOWA’s inverter, which converts the DC power into AC power and delivers it to the warehouse. The HBOWA battery banks are charged with the surplus power during the peak hours, which are used later.

This case study provides the insight of practical advantages of pv solar technology for commercial purposes and also how the modern type of solar photovoltaic cells, i.e., the PERC cells, are much more effective in making the commercial uses of solar panel more sustainable along with reducing the overall cost of operation and ensuring high level of adaptability of the devices to the ever-changing demand for power in the commercial sites like warehouses.

Real-Life Example: Off-Grid & On-Grid PV Use Cases

To understand the usefulness of solar photovoltaic technology, consider two families that utilise a straightforward principle of PV in different ways.

There is a family who lives deep in the mountains in a remote cabin, also an off-grid system. The photovoltaic system includes solar energy cells and materials explicitly designed for autonomy. The electricity from the photovoltaic panels is stored in batteries, which makes the energy available during the night or when it is overcast for essentials like a refrigerator, lighting, and charging phones.

The family enjoys the full form of independence. But, they need to be careful with the use of energy also during the cloudy days.

The second family lives in a suburb of a city. Their on-grid system feeds power back to the utility through net metering when they generate more power. Also, they can use power during the day and can draw on grid power at night. Their system has low upfront costs, and fast financial returns are available.

These two use cases show how useful photovoltaic solar technology is in different situations to meet different goals and needs.

Advantages & Limitations

Photovoltaic cells present numerous practical advantages. They produce clean electricity without any moving parts or emissions of any kind. They come in modules, and as a result, can be installed in various places, including small rooftops and open fields for industrial use. The cells also have low maintenance and operating costs.

But there are a few limitations. The cells depend on the weather, the number of daylight hours, and over the years, efficiency can also degrade, even if only slightly. In extreme conditions, efficiency is known to decrease; even a slight amount of dust and shadow can hamper the work of photovoltaic cells.

Technology is improving, however. PERC cell structures, for instance, prevent losses in a photovoltaic cell and maintain high efficiency, working under any given condition. This thus furthers the proper working of commercial as well as residential systems of photovoltaic cells.

Understanding the perks of photovoltaic cell systems helps the user in making better, more profitable long-term decisions. As the efficiency is improving with the prices falling, more and more people are adopting photovoltaic cells for different regions and different uses.

Conclusion

So, what are solar photovoltaic cells? They use the photovoltaic effect to absorb sunlight and produce electricity via silicon layers. These cells are inserted into each and every PV solar cell module to create power. With increasing demand for clean and green power, businesses, as well as homeowners, need reliable installations. HBOWA’s PERC panels can be a valid, efficient solution for commercial use. Now that you know what photovoltaic cells are and how they work, you can use this to convert to one of these sustainable power sources. For a better look, you can also search for photovoltaic cells diagram or check out the solutions provided by HBOWA.