Question

How does a PV system work, and what are some present applications of such cells?

Short answer

A Photovoltaic (PV) system works by converting sunlight into electricity with the help of PV cells made from semiconductor materials. It includes components like solar inverters, battery for energy storage and a charge controller. Its applications range from small-scale uses like solar powered calculators to large-scale power plants, providing electricity to remote locations and residential rooftop installations.

Step-by-step solution

Principle of Operation

A photovoltaic (PV) system works by converting sunlight directly into electricity. This is achieved by a photovoltaic cell, also known as a solar cell, which is made from semiconductor materials. When sunlight strikes the cell, a certain amount of it is absorbed by the semiconductor material causing the electrons in the material to get excited and generate direct current (DC) electricity.

System Components

A PV system consists of several components: PV cells that convert sunlight into direct current (DC) electricity, one or several solar inverter(s) which convert the generated DC into alternating current (AC) which can be used for everyday appliances, a battery for energy storage and a charge controller to manage the power into and out of the battery.

Current Applications

PV systems have broad applications nowadays. They are employed in various sectors due to their greener and renewable approach to power generation. Their use ranges from small scale applications like solar powered calculators and roadside emergency telephones to large scale applications like power plants. They are also commonly used to provide electricity in remote locations where there is no access to the grid such as satellites and space stations. Another important application is in the residential area where they are used as rooftop installations to offset a part of the household's electricity bill.

Key concepts

Solar Energy Conversion

Solar Energy Conversion is the core function of photovoltaic (PV) systems. These systems are designed to transform sunlight into electricity. This magical transformation begins when solar panels, made up of many photovoltaic cells, are exposed to sunlight. These cells capture energy from the sun and convert it directly into direct current (DC) electricity.
The process is simple but powerful. The photovoltaic cells absorb photons from sunlight, which then excites electrons in the semiconductor material.
This excitement propels the electrons to move, generating an electric current. The conversion of light into electricity happens in a step known as the photovoltaic effect.
Understanding this process helps us appreciate how solar panels on homes or calculators work seamlessly under the sun.

Semiconductor Materials

The magic behind photovoltaic cells lies in the Semiconductor Materials used. Semiconductors are materials with electrical conductivity between that of conductors and insulators. These materials are typically silicon, but other materials like cadmium telluride and copper indium gallium selenide are also used.
These semiconductor materials are carefully engineered and manufactured to have specific properties.
For PV cells, their main job is to create an electric field.
This is achieved by deliberately introducing impurities, a process known as doping, to create a positive and a negative side. These sides allow electrons to flow when excited by sunlight.
Understanding this is crucial because it explains the foundation of how solar energy conversion takes place.
Next time you see a solar panel, remember that deep inside lies a sophisticated array of semiconductors doing the hard work of generating electricity.

Renewable Energy Applications

PV systems are a cornerstone of Renewable Energy Applications. Their versatility has led to widespread use across various sectors, reflecting their importance in the move towards greener energy solutions.
In our homes, solar panels on rooftops can significantly offset electricity bills. They convert the ample sunlight received throughout the day into usable energy, reducing dependency on grid electricity.

• In remote or off-grid locations, PV systems provide an essential power source. They are used in remote villages, satellites, and even space stations, where traditional power supply is challenging.
• Industries are also integrating PV systems to reduce carbon footprints and utilize a reliable energy source.
• Additionally, small-scale applications enjoy their benefits too, such as solar-powered streetlights, mobile charging stations, and calculators.

The growing application of PV systems is a testament to their efficiency and adaptability.
They serve as promising tools in our pursuit of a renewable, clean energy future.