Photovoltaic systems are systems that convert solar energy into usable electricity using photovoltaic panels. They are considered a form of renewable and clean energy because they do not emit greenhouse gases and do not depend on fossil energy sources.

1. Photovoltaic panels (photovoltaic modules): These are the main components of the system, which capture sunlight and convert it into electricity. The panels are made up of photovoltaic cells, usually made of silicon, which generate electricity when exposed to sunlight.

2. Inverter (current converter): The electricity produced by photovoltaic panels is direct current (DC). The inverter converts direct current into alternating current (AC), which is used by most electrical devices in a home or building. The inverter also regulates the flow of energy to maximize the efficiency of the system.

3. Mounting system: Photovoltaic panels must be mounted on roofs or on the ground, and for this, support structures are required to secure them in place. Mounting systems are designed to ensure an optimal angle for capturing sunlight and a secure installation.

4. Batteries (optional): In some photovoltaic installations, batteries can be used to store the electricity produced during the day, so that it can also be used at night or on cloudy days. These batteries are optional, but they can increase the autonomy of the photovoltaic system.

5. Monitoring system: Many modern photovoltaic installations include a monitoring system that allows users to check the performance of the system in real time, analyze energy production and detect possible operating problems.

- Sunlight capture: Photovoltaic panels absorb sunlight and generate direct current (DC) through a process called the photovoltaic effect. When photons (particles of light) strike the photovoltaic cells, they excite electrons in the semiconducting material (usually silicon), thus generating a flow of electric current.

- Energy conversion and use: The direct current generated by the panels is converted into alternating current (AC) by the inverter and is then used to power electrical appliances in the home or building. If the system produces more energy than is consumed, the excess energy can be stored in batteries (if any) or can be delivered to the electricity grid, depending on the type of photovoltaic system installed.

1. Grid-connected photovoltaic systems (on-grid): These are the most common and are connected to the electricity grid. The energy produced by the photovoltaic system can be used directly in the home or building, and the excess energy can be sold to the energy supplier, generating income for the owner (through "net metering" systems).

2. Off-grid photovoltaic systems: These installations are not connected to the electricity grid and are used in isolated areas, where access to the grid is not available. They include batteries to store the energy produced.

3. Hybrid systems: These combine a grid-connected photovoltaic system with a storage system (batteries), so that the user can store energy for use when solar energy is not available, such as at night or on cloudy days.

- Reduction of energy costs: Provides significant long-term savings by reducing dependence on electricity purchased from suppliers.

- Clean energy source: Solar energy is a renewable source and does not produce greenhouse gas emissions.

- Energy independence: Allows users to be less dependent on the electricity grid and have greater control over their energy consumption.

- Reduced environmental impact: Using solar energy helps reduce pollution and climate change.

- Durability and low maintenance: Photovoltaic panels have a lifespan of 25-30 years and require little maintenance.

- Initial costs: Installing a photovoltaic system can require a significant initial investment, although costs have decreased significantly in recent years.

- Dependence on the sun: The performance of a photovoltaic system depends on weather conditions, and during periods of cloudy skies or in winter, energy production may decrease.

  In conclusion, photovoltaic installations are an excellent choice to harness solar energy, being both economical and ecological, and represent a long-term investment in reducing energy consumption and protecting the environment.