Converting Sunshine to Power: How Solar Cell Works
Harnessing the sun's power to meet our ever-increasing energy needs has propelled the significance of comprehending how solar cell works. This article will go into the core aspects of solar cell works, exploring their fundamentals, the different types of photovoltaic solar cells, the conversion process behind producing electricity, and the crucial role of silicon. Additionally, we'll explain how solar panels function as a system and evaluate the costs associated with implementing this clean, renewable energy source. So, what are you waiting for? Let's get started!
What Is Solar Cell?
A solar cell, also regarded as a photovoltaic (PV) cell, is a specialized semiconductor device that can convert sunlight directly into electricity. It harnesses the energy of light (photo) and transforms it into electricity (voltaic)—a process known as the photovoltaic effect. Solar cells are the most basic building blocks of solar panels, which are commonly used in a variety of settings, including power stations, satellites, and residential buildings.
Solar cells are made out of specially prepared materials called semiconductors. Silicon, known for its efficient photovoltaic conversion properties, is currently the most commonly used semiconductor material. The very important function of a solar cell is to allow light to knock electrons loose, thereby allowing them to flow freely and generate electrical current.
Types of Photovoltaic Solar Cells
Solar cells come in several types, primarily differentiated by the materials and processes used to create them.
1. Monocrystalline Silicon (c-Si): These solar cells are made from a single silicon crystal, offering the highest efficiency levels among all photovoltaic technologies. They are known for their uniform dark appearance and are relatively more expensive due to their manufacturing process.
2. Polycrystalline Silicon (mc-Si): These solar cells consist of multiple small silicon crystals. They have lower efficiency in contrast with monocrystalline cells but are generally more affordable, making them a famous choice for residential and commercial applications. These cells have a distinctly blue or multi-colored appearance due to the light scattering from multiple crystals.
3. Thin-film (TFPV): Thin-film solar cells are made by placing/depositing a very thin layer of semiconductor material onto a glass, plastic, or metal substrate. Some common types of thin-film solar cells include Cadmium Telluride (CdTe), Amorphous Silicon (a-Si), and Copper Indium Gallium Selenide (CIGS). These cells have lower efficiencies compared to crystalline silicon cells but are lightweight, flexible, and less expensive, making them suitable for a variety of applications.
4. Multi-junction (MJ): Multi-junction solar cells are composed of multiple layers of semiconductor materials, with each layer designed to capture a specific wavelength of light. This increases their efficiency significantly, making them ideal for high-performance applications like space and aerospace. However, they are more complex and expensive to manufacture.
Photovoltaic Conversion Process
How solar energy works? The photovoltaic conversion process is fundamentally about light interacting with the atoms of a semiconductor material. In a solar cell, when light photons strike the material, enough energy is imparted to dislodge electrons from the material's atoms, creating an electron-hole pair.
Solar cells are strategically built with an electric field that forces these loose electrons to move in a specific direction, generating an electrical current. This electric field corresponds to a voltage, and the product of this voltage and the current gives the power (or wattage) a solar cell can produce. This is how light (a form of energy) is converted into electricity.
Role of Silicon in Solar Cells
Silicon plays an elemental role in the function of solar cells due to its unique chemical properties. Structurally, a silicon atom has 14 electrons arranged in three different shells and needs to share 4 electrons with other atoms to stabilize itself. This characteristic makes silicon suitable for sharing and receiving electrons, a property directly learning itself about the conversion of light into electricity.
In a more advanced context, silicon in solar cells is generally 'doped' or machinated with impurities to alter its conductivity. For instance, silicon can be doped with phosphorus (N-type silicon), which creates an excess of free electrons, or with boron (P-type silicon), which created an abundance of 'holes'. These free electrons from N-type silicon, under the influence of the electric field, power through to the P-type silicon giving rise to electric current.
How Do Solar Panels Work?
How a solar panel works? A PV solar panel is a collection of solar cells electrically connected together and mounted in a frame — a solar array. Each solar cell generates a relatively small amount of electricity, but collectively, the power generated by multiple cells adds up.
When sunlight hits a PV solar panel, energy is absorbed by the solar cells and used to loosen electrons from silicon atoms, causing them to move and generate electrical current. That's how solar panel works. The current, in combination with the cell's voltage, defines the amount of power that the solar cell can produce.
The electricity produced by a PV solar panel is direct current (DC). However, most modern homes require alternating current (AC) power. Therefore, the power a solar panel generates must first pass through an inverter to transform it from DC to AC for everyday use. The practical efficiency of converting solar light into usable power varies with different technologies, with the top commercial panels having an efficiency of around 30%.
How Much Does Solar Cell Cost?
The cost of solar panels in South Africa can vary greatly based on brand, size, type, and installation expenses. A single solar panel can range from R1,800.00 (for 360 watts) to R4,200.00 (for 550 watts). For a typical 3kW solar panel system, you may expect to pay between R45,000.00 and R70,000.00. If you're interested in a 5kW solar system off grid, the cost can range from R70,000.00 to R110,000.00.
These prices also depend on the region and installer. Despite their significant upfront cost, solar panels present substantial long-term savings by cutting down or completely eliminating reliance on grid electricity.
Bear in mind that the overall cost also includes lifespan and maintenance expenses. Solar panels, appropriately installed and maintained, can function for up to 25 years or more, generating steady energy savings throughout their lifespan.
Conclusion
To conclude, understanding how solar cell works is crucial for using the sun's power and transitioning to more sustainable energy solutions. With various types of photovoltaic solar cells and the essential role silicon plays in solar panels' efficiency, the investment in solar energy becomes increasingly appealing. As the modern trend shifts towards greener practices, the lowering costs of solar cells will make this clean energy technology even more accessible, bringing us closer to a eco-friendlier future. At FusionSolar, we're dedicated to bolstering this transition, driving society closer to a cleaner, brighter future.
FAQ
Here are some commonly asked questions on how solar cell works.
What Is the Process of How Solar Cells Work?
Solar cells (photovoltaic (PV) cells) convert sunlight directly into electricity through a process called the photovoltaic effect. Initially, solar cells absorb photons from sunlight, which then energize the electrons in the atom. Next, the energized electrons move from a state of low energy to one of high energy, leaving behind 'holes.' Both the holes and the high-energy electrons then move towards respective terminals resulting in an electric circuit.
What Are the Fundamental Principles behind Solar Cells?
The fundamental principles behind solar cells are anchored in the photovoltaic effect and semiconductor physics. Essentially, solar cells rely on the principle of p-n junction semiconductor where the junction created between a p-type (positively charged) and n-type (negatively charged) semiconductor material facilitates electron movement and creates an electric field.
How Does a Solar Cell Generate Electricity?
How solar PV works? Solar cells generate electricity through a process known as the photovoltaic effect. This starts with photons from sunlight hitting solar panels that are made up of smaller units—solar cells. Each cell is made of semiconducting material usually silicon-based, layered with a positive and a negative layer. When photons are absorbed by the cell, electrons are knocked loose from their atoms. These free electrons are captured and channeled, creating an electrical current, which is then used as electricity. This entire process occurs without any moving parts, releasing no greenhouse gas emissions once installed.