Photovoltaic Technology Explained: How Solar Cells Generate Electricity

by Dec 26, 2024
Every time sunlight hits a rooftop, a huge part of it goes unused and wasted, unless a photovoltaic solar system is there to capture it. With the quiet scientific process working in the background, you simply get to witness the noiseless generation of electricity that can lower your electricity bills. From powering calculators to running households and factories, photovoltaic technology is capable of so much. This article offers an introduction to photovoltaic technology, enlightens you about certain confusing terms, and helps you understand the efficiency. Read on to know.

What is Photovoltaic Technology?

Photovoltaic or PV technology is the technique of converting sunlight directly into electricity. It works on a simple idea, which is, when sunlight falls on special materials (semiconductors), they produce an electric current. The result is clean and renewable energy that can power small devices to large solar farms. PV technology is highly beneficial for the environment as it reduces dependence on energy generated from fossil fuels.

Solar Cells

Photovoltaic cells, also referred to as solar cells, are the basic building blocks and key components in converting sunlight into electricity. The solar cells are made of a semiconductor like silicon, a natural material found in sand. Its durability, ease of processing, and high efficiency in capturing sunlight make it a worthy choice. The single photovoltaic device is very small, with a size varying from 0.5 inches to 4 inches. Generally, it produces 1 to 2 Watts of power, which is enough to power calculators or wristwatches. For large-scale applications, the cells are sandwiched between protective materials like glass and/or plastics.

Mode of Action of PV Technology

Here is the stepwise insight into how a photovoltaic solar system works:

Step 1: Sunlight Reaches Solar Cells

The sunlight, comprising photons (the tiny packets of energy), falls on the semiconductor material inside the photovoltaic (PV) cell. The cells absorb the energy of sunlight.

Step 2: Electron Excitation

The absorbed energy is transferred to the electrons in the semiconductor. The electrons are another type of tiny particle with a negative charge. When they gain extra energy from sunlight, they become active and start moving.

Step 3: Current Generation

An internal electric field in the solar cell guides these free electrons in a single direction. Their movement forms a direct current (DC) and voltage potential.

Step 4: Electricity Flow

The electrons flow through an external circuit, producing electrical energy as DC power.

Step 5: Conversion by Inverter

Since homes and appliances use alternating current (AC), the DC electricity from solar panels is sent to an inverter. This device converts DC into AC electricity, making it usable for everyday electrical devices.

What Do These Mean: Photovoltaic Cells, Panels, and Arrays

Photovoltaic technology is associated with multiple confusing terms, such as cells, panels, and arrays. These are simple once you understand. Photovoltaic Cells: As already discussed, these are the smallest building blocks of a PV solar power system. Each cell produces a small amount of power. Solar Panels or Modules: A solar panel or module is formed by connecting many photovoltaic cells together. Since one cell produces very little electricity, they are combined to increase the total power output. You can recognise solar panels or modules as the flat rectangular units commonly seen on rooftops. Solar Arrays: A solar array is a group of multiple solar panels connected together. These are used when higher electricity generation is needed. Hierarchy of photovoltaic terminologies: Solar Cell → Solar Panel → Solar Array

Efficiency of Photovoltaic Cell

The PV efficiency tells us how much electricity it can produce from the sunlight it receives. This is measured by the solar panels, which are tested under ideal light conditions, i.e., 1000 watts of sunlight per square meter at 25°C, using a solar simulator. The electricity produced in this test is called peak power. For instance, if a 1 m² panel produces 200 W, then its efficiency is 20%. The highest possible efficiency for a traditional PV cell is about 33%. It is referred to as the Shockley-Queisser limit. The actual electricity produced by a panel depends on efficiency and the amount of received sunlight. It means the regions receiving more sunlight will have more PV efficiency and produce more electricity compared to the areas receiving less sunlight.

Factors Affecting Solar Panel Efficiency

The amount of sunlight is not the only parameter impacting the electricity generation from a solar panel. There are other factors as well. Know them to get the high PV efficiency for your panel:

Temperature

The efficiency depends on temperature, with cooler temperatures improving it while higher temperatures reducing it.

Shading

Shade from buildings and trees blocks sunlight and reduces power production. Further, it may also create hot spots that damage the panel.

Climate

The angle of the sun (angle of incidence) and atmospheric conditions, such as cloud, moisture and haze, affect the amount of sunlight reaching the panel. Hence, it impacts the efficiency as well. The maximum energy can be generated when the sun is perpendicular to the face of the solar panel.

Age and Maintenance

Degradation of the material as it ages affects the efficiency of the solar panel. Adding to it, the gathered dust, dirt, and debris block the sunlight and reduce performance.

Conclusion

Photovoltaic technology, adoptable even in residential areas and busy cities, has become one of the most common solutions for generating clean and renewable energy. These versatile solar power systems can be installed in compact areas such as rooftops and other urban spaces. The result is reduced dependence on fossil fuels and, hence, lower dependence on grid electricity. A photovoltaic solar system works on the simple principle of harvesting sunlight to generate current. The current then flows through the inverter to power routine use appliances. The number of photovoltaic cells, the angle of the sun, sunlight hours, and the temperature are some factors that influence the generated output.

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Considering the different aspects while choosing solar panels as a novice can be overwhelming. Livfast is the brand that believes in helping our customers make independent decisions by making them aware. Offering solar panels for both residential and commercial use, we invite you to explore our reliable and cost-effective solutions and choose the one that suits your needs. Get in touch with us now at +91 7428191001, +91 7428191000, or livserv@sar-group.com to let us help you choose the:
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FAQ's

What are solar farms?

Solar farms are also referred to as solar fields and solar parks. These areas have numerous solar panels placed across acres of land for maximum utilisation of solar energy. The power generated at solar farms is used to feed directly into the grid. 

Is this Helpful?

You can increase the PV solar power system efficiency by considering the following points: 

  • Choose the photovoltaic panels with high efficiency 
  • Avoid the installation of panels in shaded areas 
  • Get the solar panel installed by a professional to ensure the right direction, tilt, wiring, and spacing 
  • Ensure regular maintenance by cleaning the panels

Is this Helpful?

There are numerous benefits of incorporating a PV solar power system into both residential and commercial areas. These include providing clean, renewable, and sustainable energy, lowering energy bills, increasing property value, and offering power in remote areas. 

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The main types of solar panels are monocrystalline, polycrystalline, and thin-film solar panels. The more advanced types of solar panels include PERC, bifacial, and others.

Is this Helpful?

Yes, solar panels are effective during cloudy days. However, they produce less power on such days in comparison to sunny days. The effectiveness comes from their ability to generate electricity from diffused sunlight that passes through the clouds.

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