When you think of saving the world from greenhouse gases and extreme pollution, solar energy strikes your mind inevitably. The cornerstone of renewable energy, solar panels offer a clean, sustainable, and cost-effective alternative to fossil fuel-powered energy sources.
Please visit our website for more information on this topic.
The United Nations Climate Action report reveals fossil fuels to be the biggest culprit of global climate change with 75% greenhouse gas emissions. Whether it&#;s the International Energy Association or the United Nations Environment Programme, all agree that solar energy is the answer to the global energy crisis and global climate change. Solar PV modules are at the forefront of the energy transition the world needs to achieve zero emission goals. Well, this makes solar panels a hot topic for study, research, and evaluation of their key components and their functionality.
This article discusses all the key components of solar panels, their functions, their material type, and their specifications. The article also mentions their placement in the solar panel along with their importance.
This article discusses all the key components of solar panels, their functions, their material type, and their specifications. The article also mentions their placement in the solar panel along with their importance.
Photovoltaic (PV) cells convert light energy into electrical energy through the photovoltaic effect. The primary component, solar cells are the fundamental building blocks of solar panels.
Functions:
Importance level
PV cells are the core components of solar panels that generate electricity. Without these cells, solar panels would be unable to convert sunlight into usable electrical energy, making them the most critical elements in solar power generation.
Material made:
PV cells are primarily made from silicon, which can be either monocrystalline, polycrystalline, or amorphous. Other materials used in some specialized PV cells include gallium arsenide, cadmium telluride, and copper indium gallium selenide.
Position/placement in solar panel:
PV cells are arranged in a grid-like pattern on the surface of the solar panel (sandwiched between the protective glass cover on top and the backsheet below).
Maintenance needs:
PV cells generally require minimal maintenance (regular cleaning to remove dust and debris is enough). Periodic inspections for any physical damage or degradation are recommended.
Best Specification: The best cells also have a low-temperature coefficient, around -0.25% to -0.30% per °C.
Solar frames are the structural components that encase and support the solar panel. The standard material is aluminum and therefore these are parallelly known as solar aluminum frames also.
Functions:
Importance level
Solar frames are crucial for the overall mechanical stability, durability, and longevity of solar panels. They play a vital role in protecting the internal components and maintaining the panel&#;s performance under various environmental conditions.
Material made:
Solar frames are typically made of anodized aluminum, chosen for their impressive strength-to-weight ratio, corrosion resistance, and high thermal conductivity.
Position/placement in solar panel:
The frame is positioned around the perimeter of the solar panel, encasing the glass, solar cells, and other internal components.
Maintenance needs:
Solar frames require minimal maintenance. Periodic visual inspections for any signs of damage or corrosion are necessary. Occasional cleaning may be necessary to remove accumulated dirt or debris.
Best specifications:
High-quality solar frames should have a corrosion-resistant anodized coating. Aluminium Alloy is most suitable.
A solar backsheet is the outermost layer on the rear side of a photovoltaic (PV) module, designed to protect the internal components and provide electrical insulation while serving as a weatherproof barrier against environmental elements.
Functions:
Importance level:
Backsheets are crucial for protecting sensitive internal components from environmental degradation and electrical hazards, directly impacting the module&#;s lifespan and efficiency.
Material made:
Backsheets are typically made of multiple layers of polymers, which can include fluoropolymers (like PVDF) or non-fluoropolymers (such as PET). The choice of material depends on the specific requirements and design of the solar panel.
Position/placement in solar panel:
The backsheet is positioned as the bottommost layer of the solar panel, directly beneath the lower layer of EVA (ethylene vinyl acetate) encapsulant and the solar cells.
Maintenance needs:
Periodic visual inspections for any signs of degradation, discoloration, or physical damage. Regular cleaning may be necessary to remove accumulated dirt or debris that could affect the panel&#;s performance. However, there are no extensive maintenance needs.
Best Specifications: High-quality solar backsheets typically have a thickness of 300-350 μm, with a solar reflectance of at least 77%, and a dielectric strength of >600 V/mil.
Solar glass is a specialized type of glass designed for use in solar panels. This particular component of solar panels comes with an anti-reflective coating and high transparency to maximize sunlight transmission.
Functions:
Importance Level:
Solar glass is crucial for safeguarding the photovoltaic cells and delicate parts of solar panels against environmental elements. It directly impacts the efficiency and performance of the solar panel.
Material made:
Solar glass is typically made from low-iron content silicate glass, also known as ultra-white embossed glass. It&#;s composed of raw materials including quartz sand, soda ash, limestone, dolomite, and various other compounds.
Position/placement in solar panel:
Solar glass is positioned as the topmost layer of the solar panel, covering and protecting the entire structure of photovoltaic cells and other components.
Maintenance needs:
Periodic cleaning with soap and water to remove accumulated dirt or dust. Regular visual inspections for any signs of damage or degradation are recommended.
Best specifications:
High-quality solar glass typically has a light transmittance of over 91% for uncoated glass, with coated glass reaching up to 93.5% transmittance. It should also have high mechanical strength and density of Sink & Float Method:2. ± 0. gram/cc.
Solar encapsulants are polymer materials used to encapsulate and protect the photovoltaic cells and other internal components of solar panels.
Functions:
ORIENT supply professional and honest service.
Importance level in a solar panel:
They are essential for mitigating stability issues and protecting the internal components from environmental stresses.
Material made:
Solar encapsulants are typically made of polymeric materials, with ethylene-vinyl acetate (EVA) being the most commonly used. Other materials include polyvinyl butyral (PVB) and thermoplastic polyolefin (TPO).
Position/placement in solar panel:
Encapsulants are positioned between the front glass and the solar cells, as well as between the cells and the backsheet, effectively sandwiching the PV cells.
Maintenance needs:
Solar encapsulants generally do not require direct maintenance.
Best specifications:
High-quality encapsulants should have excellent UV resistance, thickness of 380 to 600 GSM, low moisture vapor transmission rate (MVTR <2 g/m²/day), and maintain their properties for 25+ years. They should also have a high light transmittance (>90%) and good adhesion to both glass and backsheet
A solar junction box is an enclosure attached to the back of a solar panel that houses electrical connections and provides an interface for connecting the panel to the larger solar system.
Functions:
Importance level
The junction box is a crucial component of solar panels, acting as the connector between the solar cells and external devices. It plays a vital role in protecting internal components and ensuring proper power flow.
Material made:
Junction boxes are typically made of weather-resistant materials such as PPO (polyphenylene ether) or PPE (polypropylene), which offer high rigidity, heat resistance, and excellent electrical properties.
Position/placement in solar panel
The junction box is attached to the back of the solar panel (TPT &#; Tedlar-Polyester-Tedlar backsheet) with silicon adhesive.
Maintenance needs:
Junction boxes generally require minimal maintenance. Regular visual inspections for signs of damage, corrosion, or water ingress are recommended.
Best specifications:
High-quality junction boxes should be certified (e.g., TÜV), have effective heat regulation, and provide reliable long-term safety.
A solar battery is an energy storage device that stores excess electricity generated by solar panels for later use when sunlight is not available or during power outages.
Functions:
Importance level:
Critical for maximizing solar energy utilization and providing a consistent power supply. Solar batteries enable 24/7 use of solar energy, significantly enhancing the effectiveness of solar panel systems.
Material made:
Most commonly made of lithium-ion, though some use lead-acid or other advanced battery chemistries.
Position/placement in solar panel:
Installed separately from the solar panels, often indoors or in a protected outdoor area near the main electrical panel.
Maintenance needs:
Regular monitoring of charge levels and periodic capacity checks are necessary. Replacement is typically required every 5-10 years, depending on the battery type and usage.
Best specifications:
High energy density (5 to 50 kWh capacity) and long cycle life (+ cycles).
Apart from the above discussed major solar panel components below are also important.
Each component of solar panels, from the photovoltaic cells to the inverters, plays a crucial role in converting sunlight into usable electricity. Component analysis ensures that solar panels meet rigorous quality standards, are free from defects, and perform flawlessly.
When light shines on a photovoltaic (PV) cell &#; also called a solar cell &#; that light may be reflected, absorbed, or pass right through the cell. The PV cell is composed of semiconductor material; the &#;semi&#; means that it can conduct electricity better than an insulator but not as well as a good conductor like a metal. There are several different semiconductor materials used in PV cells.
When the semiconductor is exposed to light, it absorbs the light&#;s energy and transfers it to negatively charged particles in the material called electrons. This extra energy allows the electrons to flow through the material as an electrical current. This current is extracted through conductive metal contacts &#; the grid-like lines on a solar cells &#; and can then be used to power your home and the rest of the electric grid.
The efficiency of a PV cell is simply the amount of electrical power coming out of the cell compared to the energy from the light shining on it, which indicates how effective the cell is at converting energy from one form to the other. The amount of electricity produced from PV cells depends on the characteristics (such as intensity and wavelengths) of the light available and multiple performance attributes of the cell.
An important property of PV semiconductors is the bandgap, which indicates what wavelengths of light the material can absorb and convert to electrical energy. If the semiconductor&#;s bandgap matches the wavelengths of light shining on the PV cell, then that cell can efficiently make use of all the available energy.
Learn more below about the most commonly-used semiconductor materials for PV cells.
Silicon is, by far, the most common semiconductor material used in solar cells, representing approximately 95% of the modules sold today. It is also the second most abundant material on Earth (after oxygen) and the most common semiconductor used in computer chips. Crystalline silicon cells are made of silicon atoms connected to one another to form a crystal lattice. This lattice provides an organized structure that makes conversion of light into electricity more efficient.
Solar cells made out of silicon currently provide a combination of high efficiency, low cost, and long lifetime. Modules are expected to last for 25 years or more, still producing more than 80% of their original power after this time.
A thin-film solar cell is made by depositing one or more thin layers of PV material on a supporting material such as glass, plastic, or metal. There are two main types of thin-film PV semiconductors on the market today: cadmium telluride (CdTe) and copper indium gallium diselenide (CIGS). Both materials can be deposited directly onto either the front or back of the module surface.
CdTe is the second-most common PV material after silicon, and CdTe cells can be made using low-cost manufacturing processes. While this makes them a cost-effective alternative, their efficiencies still aren't quite as high as silicon. CIGS cells have optimal properties for a PV material and high efficiencies in the lab, but the complexity involved in combining four elements makes the transition from lab to manufacturing more challenging. Both CdTe and CIGS require more protection than silicon to enable long-lasting operation outdoors.
Perovskite solar cells are a type of thin-film cell and are named after their characteristic crystal structure. Perovskite cells are built with layers of materials that are printed, coated, or vacuum-deposited onto an underlying support layer, known as the substrate. They are typically easy to assemble and can reach efficiencies similar to crystalline silicon. In the lab, perovskite solar cell efficiencies have improved faster than any other PV material, from 3% in to over 25% in . To be commercially viable, perovskite PV cells have to become stable enough to survive 20 years outdoors, so researchers are working on making them more durable and developing large-scale, low-cost manufacturing techniques.
Organic PV, or OPV, cells are composed of carbon-rich (organic) compounds and can be tailored to enhance a specific function of the PV cell, such as bandgap, transparency, or color. OPV cells are currently only about half as efficient as crystalline silicon cells and have shorter operating lifetimes, but could be less expensive to manufacture in high volumes. They can also be applied to a variety of supporting materials, such as flexible plastic, making OPV able to serve a wide variety of uses.PV
Another strategy to improve PV cell efficiency is layering multiple semiconductors to make multijunction solar cells. These cells are essentially stacks of different semiconductor materials, as opposed to single-junction cells, which have only one semiconductor. Each layer has a different bandgap, so they each absorb a different part of the solar spectrum, making greater use of sunlight than single-junction cells. Multijunction solar cells can reach record efficiency levels because the light that doesn&#;t get absorbed by the first semiconductor layer is captured by a layer beneath it.
While all solar cells with more than one bandgap are multijunction solar cells, a solar cell with exactly two bandgaps is called a tandem solar cell. Multijunction solar cells that combine semiconductors from columns III and V in the periodic table are called multijunction III-V solar cells.
Multijunction solar cells have demonstrated efficiencies higher than 45%, but they&#;re costly and difficult to manufacture, so they&#;re reserved for space exploration. The military is using III-V solar cells in drones, and researchers are exploring other uses for them where high efficiency is key.
Concentration PV, also known as CPV, focuses sunlight onto a solar cell by using a mirror or lens. By focusing sunlight onto a small area, less PV material is required. PV materials become more efficient as the light becomes more concentrated, so the highest overall efficiencies are obtained with CPV cells and modules. However, more expensive materials, manufacturing techniques, and ability to track the movement of the sun are required, so demonstrating the necessary cost advantage over today's high-volume silicon modules has become challenging.
Learn more about photovoltaics research in the Solar Energy Technologies Office, check out these solar energy information resources, and find out more about how solar works.
Contact us to discuss your requirements of Poly Solar Cell. Our experienced sales team can help you identify the options that best suit your needs.