A photovoltaic solar installation is a set of elements that have the purpose of producing electricity from solar energy. It is a type of renewable energy that captures solar radiation through photovoltaic panels.
The different parts of a photovoltaic system vary slightly depending on whether they are grid-connected photovoltaic installations or isolated systems.
In isolated installations, the energy generated can be stored using solar batteries and charge regulators. In the case of installations connected to the grid, the electricity generated is supplied to the general electricity grid for distribution.
The main elements of a photovoltaic solar installation are:
1. Photovoltaic Solar Panels
The photovoltaic solar panel is the element that captures solar radiation and is responsible for transforming solar energy into electricity through the photovoltaic effect. This type of solar panels are made up of small elements called photovoltaic cells.
The photovoltaic cell is the part of the photovoltaic panel responsible for transforming solar radiation into electrical energy thanks to the photovoltaic effect. The result is an electrical current in direct current.
The photovoltaic cells are encapsulated in two layers between a front sheet of glass and a back layer of a thermoplastic polymer or other glass sheet. The glass sheet is used when it is desired to obtain modules with some degree of transparency.
Usually this set of elements is framed in an anodized aluminum structure to increase resistance and facilitate the anchoring of the photovoltaic module.
The most common photovoltaic cells are silicon, and can be divided into three subcategories:
Monocrystalline silicon photovoltaic cells.
Polycrystalline silicon photovoltaic cells, with higher performance.
Amorphous silicon cells are the least efficient but least expensive.
2. Power Inverters
The inverter is an electronic device responsible for converting the current generated in the photovoltaic panel in such a way that it is optimal for the electricity supply. An inverter converts the generated direct current into alternating current.
The photovoltaic solar panel of this type of installation provides electricity in the form of direct current. This current can be transformed into alternating current by means of the current inverter and injected into the electrical network or into the internal network.
The process, simplified, would be as follows:
Power is generated at low voltages (380-800 V) and in direct current.
It is transformed with a power inverter into alternating current.
In electrical power plants of less than 100 kW, energy is injected directly into the low-voltage distribution network. And for powers greater than 100 kW, a transformer is used to raise the energy to medium voltage and it is injected into the transport networks.
3. Solar Trackers
Solar trackers are mechanisms that orient the position of the photovoltaic panels depending on the position of the Sun to increase their performance. Its use is quite common in the production of solar energy.
Solar trackers make it possible to greatly increase solar production, around 30% for the former and an additional 6% for the latter, in places with high direct radiation.
There are several types of solar trackers:
Two-axis solar trackers: the surface of the photovoltaic panel is always perpendicular to the Sun.
Solar trackers on a polar axis: the surface of the solar panel rotates on an axis facing south and tilted at an angle equal to latitude.
Solar trackers on an azimuthal axis: the surface rotates on a vertical axis, the angle of the surface is constant and equal to the latitude.
Solar trackers on a horizontal axis: the surface rotates on a horizontal axis and is oriented in a north-south direction.
4. Electrical Wiring
Electrical wiring is the element that transports electrical energy from its generation, for its subsequent distribution and transport. Its dimensioning is determined by the most restrictive criterion between the maximum potential difference and the maximum admissible intensity.
Obviously, the dimensioning of the electrical wiring is much greater in the case of solar installations connected to the network. In the case of isolated installations, it is only necessary to transfer the electrical energy locally, generally to the electric batteries.
5. Batteries and Charge Regulators
In the case of autonomous solar installations, the use of batteries is necessary to be able to store the electrical energy generated. For the correct operation of these elements, a charge regulator is also necessary to guarantee an optimal filling of the batteries and thus extend the useful life of the batteries.