Solar panels are renewable energy sources made of photovoltaic cells that efficiently transform sunlight into electricity by the photovoltaic effect. The alternative Name for solar panels is photovoltaic panels.
The Importance of Solar Panels in Modern Energy Solutions plays a significant role owing to renewable nature and environmental benefits. They help reduce our dependence on fossil fuels, cut greenhouse gas emissions, and encourage low-carbon energy production.
Undoubtedly, Solar panels are most commonly used to generate electricity and heat. We benefit from solar energy to generate electricity for residences, businesses, and other industrial purposes, as well as to provide heat for various applications. Also, Solar panels are used in multiple places like Residential rooftops, Commercial buildings, and Utility-scale solar farms.
These installations contribute to expanding solar power generation, eliminating electrical losses, and promoting green energy independence.
In order to understand how solar panels produce electricity for your home, you will have to know the science of Solar Panels, the Photovoltaic Effect, as well as technologies like Thin Film, Organic, Quantum Dot, and Perovskites that are emerging alternatives to Silicon solar cells.
Let us explore the answers to many common questions whether solar panels work at night, different types of solar panels and factors affecting Solar Panel Efficiency.
Solar energy is defined as the sun’s heat and radiant light, which is a renewable source converted into electricity using various technologies, like Solar/PV panels.
The Sun-released energy is Solar radiation in the form of electromagnetic waves like — visible light, ultraviolet light, infrared light, and other wavelengths.
The potential of solar energy is limitless. The volume of solar energy that reaches the Earth’s surface in 1 hour is far greater than the world’s total energy consumption for 365 days. It focuses on the massive potential for making use of solar energy as a zero-carbon and abundant form of energy. There is a lot more to know about solar energy.
The Science of Solar Panels: The Photovoltaic Effect
Solar panels are most commonly made of silicon, a semiconductor material, in combination with different components such as glass, metal, and wiring.
The most important components of solar panels consist of photovoltaic cells, generally known as solar cells, which are attached and arranged within a frame. These cells are placed between protective glass layers coated with materials like ethylene-vinyl acetate (EVA).
Photovoltaic cells are the technologically advanced components of solar panels, which are made of semiconductor materials, such as crystalline silicon, that help convert sunlight into electricity.
Silicon is used in photovoltaic cells because of the way it conducts electricity after it is exposed to sunlight. However, it is a bad conductor in its purest form. Therefore, doping the solar cells by the process of placing impure substances into the silicon crystal structure to improve its electrical conductivity properties.
The most common doping materials used in solar cells are Phosphorus to create excess electrons (n-type doping) and Boron to create electron imbalance or holes (p-type doping).
Usually, Solar panels generate electricity using the photovoltaic effect, discovered by Alexandre-Edmond Becquerel in 1839, where materials, like silicon produce an electric current after they are exposed to sunlight.
Solar panels work by generating electricity when sunlight hits the photovoltaic cell’s surface, exciting the electrons making them pass through the material, and thus creating an electric current. This electron flow is absorbed by the electrical circuit connected to the solar panel and produces usable electricity.
What are the alternatives to Silicon solar cells?
Here are a few Alternatives to Silicon Solar Cells:
1. Thin Film Solar
Thin film solar cells comprise a few semiconductor materials placed in thin layers over a base material like glass, plastic, or metal. Besides this, there are so many things to know about thin-film solar panels.
Benefits of Thin Film Solar:
Flexible
Lightweight
Low-cost Manufacturing
Types of Thin Film Solar:
Amorphous Silicon (a-Si)
Cadmium Telluride (CdTe)
Copper Indium Gallium Selenide (CIGS).
2. Organic Solar Cells
Organic solar cells make use of organic (carbon-based) materials as the active layer in the photovoltaic device. All of these materials are usually polymers or very tiny organic molecules.
Benefits of Organic Solar Cells:
Flexibility
Low-cost manufacturing
Large-scale production
Types of Organic Solar Cells:
Polymer solar cells
Compact or Small-molecule solar cells
Hetero junction thin-film solar cells
Tandem solar cells
3. Quantum Dot Solar Cells
Quantum dot solar cells are composed of quantum dots, and nanoscale semiconductor particles, which are made of materials like cadmium selenide or lead sulphide, into the solar cell structure.
Benefits of Quantum Dot Solar Cells:
Tunable band gap
The potential for high efficiency
Compatibility with solution-based processing
Types of Quantum Dot Solar Cells:
Colloidal quantum dot (CQD) solar cells
Pbs quantum dot heterojunction solar cells
Perovskite quantum dots
Schottky solar cells
Meg solar cells
4. Perovskite Solar Cells
Perovskite solar cells (PSCs) are a specific form of thin-film photovoltaic (PV) technology. They are created using synthetic crystals that closely resemble the crystal structure of a naturally found mineral. PSCs are structures made up of multilayered materials that are formed by printing, coating, or vacuuming laid down on an internal base layer. You can also learn more about Perovskite solar cells.
Benefits of Perovskite Solar Cells:
Charge-carrier mobilities
Create lightweight solar panels
Hybrid-tandem partners
Excellent Light absorption
Optoelectronic applications
Low production costs
Types of Perovskite Solar Cells:
Regular n-i-p structures
Inverted p-i-n structures
ETL free configurations
HTL free configurations
Perovskite-silicon tandem architectures
How do solar panels produce electricity for your home?
You can entirely rely on Solar panels to provide electricity for your home through the following step-by-step process:
1. Absorption of Sunlight, using Solar panels installed on the roof or in an open area, absorbs sunlight during the day.
2. Photovoltaic Conversion, through which solar panel cells convert the captured sunlight into direct current (DC) electricity through the photovoltaic effect.
3. Inverter Conversion, by which the DC electricity generated by the solar panels is then fed into an inverter, further converted into alternating current (AC), mostly used in homes.
4. Electricity Consumption of home appliances is obtained from the AC electricity produced by the solar panels.
5. Surplus Electricity can be sent back to the grid if the solar panels supply more electricity than what your home requires, and this process is achieved through net metering.
6. Net metering is a billing system that makes it possible for homeowners with solar panels to claim power credits for the surplus electricity they send back into the grid. Hence, these credits can compensate for the electricity they use from the grid when their solar panels are not able to generate enough electricity (such as at night).
7. Off-grid electricity is a type of system where residential buildings are not connected to the utility grid. However, solar panels can continue to provide electricity by using a battery system. Any excess electricity generated at the end of the day is stored in batteries to use when solar production is insufficient (at night or on cloudy days). Hence, it makes it possible for homes to depend completely on solar energy for their electricity needs, even while disconnected from the grid.
Do Solar Panels work at night?
Solar panels do not produce electricity at night because they are dependent on sunlight to produce electrical energy using the photovoltaic effect. In the same way, their power to perform is greatly decreased on cloudy days.
However, the solar panel’s efficiency rate fluctuates based on factors like — weather temperatures, panel placement, sun exposure, and the different kinds of solar cells used.
What are the different types of solar panels?
Here are the 5 different types of solar panels, namely:
Monocrystalline Silicon
Polycrystalline Silicon
Thin-Film Solar
Bifacial Solar Panels
Concentrated Photovoltaic (CPV)
The most common type of solar panels are the Monocrystalline and polycrystalline silicon panels. Further, thin-film solar panels follow it. Also, Bifacial panels and CPV systems are very less common, but it is gradually gaining popularity in a few applications.
Here is a detailed table describing the benefits of solar panels:
TYPE OF SOLAR PANEL
BENEFITS
Monocrystalline and polycrystalline panels
High efficiency
Durability
Long lifespan
Thin-film solar panels
Lightweight
Flexible
Unconventional installation areas
Bifacial panels
High energy production
Captures sunlight in both sides
CPV systems
Reflecting sunlight efficiently
Efficient photovoltaic cells
What is the efficiency of solar panels?
The maximum efficiency of solar panels varies depending on the technology used. Nowadays, the highest efficiency for commercial solar panels is around 21-24% for monocrystalline silicon panels. At the same time, it is 15-20% for polycrystalline silicon panels. Recently developed technologies like — perovskite and multi-junction solar cells have already established the possibilities for higher efficiencies under the test settings in the laboratory. You can also learn about monocrystalline vs polycrystalline in detail to decide which panel would be best for you.
Factors that affect Solar Panel Efficiency are:
Solar panel types and technologies
Material Quality and manufacturing process
Temperature and sunlight level
Panel position and the tilt angle
Shading and obstructed view
Dust, dirt, and pollutant
Electrical loss in wiring and inverter systems
Therefore, the solar panel efficiency rates are completely based on these above factors. However, timely maintenance and efficient system design are essential for improving the performance of solar panels.
Ray is an avid reader and writer with over 25 years of experience serving various domestic and multinational private and public energy companies in the USA.
