Photovoltaic (PV) technology is a method of generating electrical energy from sunlight. PV cells are made from semiconductor materials that directly convert sunlight into electricity. These cells are typically a few centimeters in size and each generates about 1-2 W of power. Photovoltaic cells are often coated with protective materials such as glass and plastic to safeguard them from external factors.

OPERATING PRINCIPLE OF PV CELLS

PV cells are stimulated by photons from sunlight, which release electrons from the material's atoms. These free electrons create an electric current, producing direct current (DC) electricity. This electricity is generally not used directly but is typically converted into alternating current (AC) before being used in homes.

CONNECTING PV CELLS

Since the amount of electric current produced by a single PV cell is small, cells are combined to form larger units known as modules or panels. These panels can either operate independently or be connected to form larger systems called arrays. This modular structure allows photovoltaic systems to be scaled to meet both small and large energy needs.

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COMPONENTS OF A PHOTOVOLTAIC SYSTEM

1. Solar Panels: Solar panels consist of photovoltaic cells. The sunlight that falls on the cells is converted into electrical energy through the photovoltaic effect. Most solar panels are made of crystalline silicon material, which has a theoretical efficiency limit of 33%. Other semiconductor materials are also used, but these panels are more expensive.

2. Inverters: The electricity produced by photovoltaic systems is in direct current (DC) form. However, since the electricity used in homes is alternating current (AC), this DC needs to be converted into AC. This is done using inverters, which convert the DC electricity into AC to make it compatible with home appliances. Inverters typically operate with high efficiency and can achieve efficiencies greater than 90% without compromising safety.

3. Racking System (Mounting Structures): Photovoltaic panels are placed on special mounting systems to capture the sun's energy most efficiently. These mounting structures are made from durable materials such as aluminum or steel and ensure the panels are resistant to extreme weather conditions like wind. Additionally, the panels are grounded to ensure electrical safety. These mounting systems can be installed with ballast on flat roofs or with fixed systems on slanted roofs. Some systems include tracking systems that allow the panels to follow the sun, though these systems are more expensive.

4. Other Components

• Combiners: Combiners bring multiple electrical cables together and include fuses for safety purposes.
• Disconnects: These switches separate electrical components from one another, enabling maintenance and repairs.
• Fuses and Circuit Breakers: Protect electrical systems from overcurrent and ensure that the system shuts down when necessary.
• Electric Meter: Electric meters measure the energy entering and exiting the system. Bidirectional meters are used to track the energy production of solar energy systems.

OPERATING PRINCIPLE OF PHOTOVOLTAIC SYSTEMS AND HIGH-CAPACITY SYSTEMS

In a photovoltaic system, sunlight is absorbed by photovoltaic cells, which generate DC electricity. This electricity is then converted into AC via inverters. Additionally, large photovoltaic systems can be connected to electrical grids, allowing the energy produced to be shared with others.

NOTABLE LARGE-SCALE PHOTOVOLTAIC SYSTEMS

• Solar Star PV Power Station: Generates 579 MW of power.
• Topaz Solar Farm and Desert Sunlight Solar Farm: Each generates 550 MW of power.
• These large-scale facilities are connected to electrical grids and provide clean energy to vast areas.

ADVANTAGES OF PHOTOVOLTAIC SYSTEMS

• Modular Structure: Depending on needs, photovoltaic systems can be scaled from small residential setups to large power plants.
• Clean Energy: Electricity production from solar energy does not release carbon emissions, making it an environmentally friendly energy source.
• Economic and Affordable: Due to technological advancements and cost reductions, photovoltaic systems have become more accessible.

In conclusion, Photovoltaic (PV) systems are one of the most common methods of efficiently generating electricity from solar energy. Suitable for small homes and large energy plants, these systems offer an environmentally friendly energy alternative and are becoming more popular daily.