Photovoltaic systems are electrical systems that generate power using solar energy, a renewable and inexhaustible source. This technology plays a crucial role in the current global energy transition and finds widespread applications in residential and industrial sectors.


How Photovoltaic Systems Work

The core component of a photovoltaic system is the solar panel, also known as a solar cell panel. These panels consist of numerous photovoltaic cells that can absorb sunlight and convert it into electricity. These cells are made of semiconductor materials, with silicon being the most commonly used material. When sunlight hits the photovoltaic cell, electrons in the semiconductor are excited, generating a flow of current. The direction of this electron flow creates a voltage, similar to the positive and negative terminals of a battery. By connecting multiple photovoltaic cells, a photovoltaic module is formed, increasing the electricity generation capacity.


How Photovoltaic Systems Work


Modules in a Photovoltaic System

Photovoltaic modules play a critical role in a photovoltaic system. When sunlight shines on the module, electrons within the photovoltaic cells are released, producing direct current (DC) electricity. To utilize this DC electricity for household and industrial purposes, a photovoltaic system also requires an inverter. An inverter is an electronic device that converts DC electricity into alternating current (AC), meeting the user's power demands. Inverters also incorporate protective devices to ensure the system operates safely during power failures or grid disturbances.

In addition to photovoltaic modules and inverters, a photovoltaic system includes other important components. Support structures are used to mount the photovoltaic modules, typically installed on rooftops. Cables are used to transmit electricity from the photovoltaic system to the location where users require it. Furthermore, a photovoltaic system can be equipped with monitoring systems to remotely track energy generation and consumption, as well as the status of the inverter. Energy storage systems can be employed to store excess electricity generated during the day for use during nighttime or inclement weather, maximizing the utilization of the photovoltaic system's energy output.


Modules in a Photovoltaic System


Grid-Connected and Off-Grid Systems

There are two main types of photovoltaic systems: grid-connected systems and off-grid systems.

An off-grid system is an independent power system that does not rely on the traditional electrical grid. It is suitable for remote areas or situations where disconnection from the grid is desired. Off-grid systems consist of components such as photovoltaic panels, battery storage systems, and inverters, which convert solar energy into electricity and store it in batteries for use during nighttime or cloudy days.

A grid-connected system is a system that connects the photovoltaic system to the conventional power grid. Photovoltaic panels convert solar energy into AC electricity using inverters and inject it into the grid. In this way, the photovoltaic system can provide power to the user while also feeding excess electricity back into the grid. When more power is needed, users can draw power from the grid, and when the photovoltaic system generates more electricity than required, the surplus power is fed into the grid, sometimes resulting in grid feed-in tariffs or subsidies.

Off-grid systems achieve relatively independent power supply but require larger energy storage and management systems to cope with the intermittent nature of solar energy supply. Grid-connected systems enable users to fully utilize solar power generation while maintaining a connection to the grid for a stable power supply. Whether it is an off-grid system or a grid-connected system, both are sustainable energy solutions that harness solar power, helping reduce reliance on traditional energy sources, lower carbon emissions, and contribute to sustainable development.


Grid-Connected and Off-Grid Systems


Differences between Industrial and Residential Photovoltaic Systems

Industrial photovoltaic systems and residential photovoltaic systems can be explained in simple terms:

Scale: Industrial photovoltaic systems are larger, resembling large-scale power plants, while residential photovoltaic systems are like small-scale generators.

Usage: Industrial photovoltaic systems primarily serve the energy needs of factories, commercial buildings, and other large enterprises, while residential photovoltaic systems are designed to meet the electricity demand of households.

Installation location: Industrial photovoltaic systems require more space and may be installed on large plots of land or on the roofs of large buildings. Residential photovoltaic systems are typically installed on residential rooftops.


Residential Photovoltaic Systems


Electricity consumption: Due to the higher power demand for production and equipment operation, industrial and commercial enterprises require more electricity, resulting in higher electricity demands for industrial photovoltaic systems. Residential photovoltaic systems mainly meet the daily electricity needs of households.

System complexity: Industrial photovoltaic systems typically require more complex energy management systems to monitor and optimize energy production and usage. Residential photovoltaic systems are relatively simpler, typically only requiring basic monitoring systems.

Cost and investment: Due to their larger scale, industrial photovoltaic systems require higher investment costs. Residential photovoltaic systems have lower costs, making them suitable for meeting household electricity needs.


Differences between Industrial and Residential Photovoltaic Systems


In summary

In the light of solar energy, we are ushering in a more sustainable future. Photovoltaic (PV) systems, an innovative technology that utilizes solar power to generate electricity, not only play a key role in the energy transition, but also provide us with a clean, renewable energy option. By fully utilizing solar energy, we can reduce our dependence on traditional energy sources, lower carbon emissions, and contribute to environmental protection and sustainable development.



September 22, 2023