In the market, we can find many ways to take advantage of solar energy, the most well-known and widespread being photovoltaics.

The “solar panels”Are divided into three main macro-categories:

  1. Photovoltaic solar panels. They use solar cells to convert the sun’s heat into electricity. This process takes place thanks to the properties of silicon (of which solar cells are made) capable of producing electricity when it is irradiated by the sun.
  2. Thermal solar panels. They convert solar energy into thermal energy (heat). Thermal panels DO NOT produce electricity unlike photovoltaic panels. The purpose of a solar thermal panel is therefore to produce hot water which can be used for washing, cooking, washing dishes or heating a house by heating.
  3. Concentrated solar panels. Thermodynamic solar panels are used to generate energy in a concentrating solar system. Thermodynamic solar panels are essentially parabolic mirrors capable of concentrating solar energy towards a collector in which a thermovector liquid flows. This liquid, whose temperature can reach 600 ° C, allows the generation of steam and energy suitable for industrial use. To produce energy in this way, it is therefore necessary to have a large area on which to place the thermodynamic solar panels.

Types of photovoltaic solar panels by their internal structure.

In the types of solar panels, we are interested in photovoltaic panels because they are the most widespread.

The most common types of photovoltaic panels are monocrystalline, black and polycrystalline blue. Today’s commercial photovoltaic panels are made of silicon, but due to a difference in the production process, the panels differ in color.

The solar cell consists of a wafer whose structure is homogeneous and then chemically treated.

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A single crystal silicon module cell is made of a single silicon crystal, which guarantees maximum conductivity through the perfect alignment of pure silicon atoms. The efficiency of monocrystalline silicon modules is about 15% to 17% and the photovoltaic cells are dark blue octagonal in shape.


In polycrystalline panels, silicon crystals are fan-shaped, which makes the panels blue.

The platelet is not structurally homogeneous, but is organized into locally ordered grains. It is obtained by recycling discarded electronic components, that is to say “silicon waste” which is remelted to obtain a compact crystalline composition: the cells of a polycrystalline module are made up of a set of several silicon crystals. The efficiency of a polycrystalline modulus is about 14% to 16% and the cells are dark blue and square.

Red photovoltaic panels.

Red photovoltaic modules are types of polycrystalline photovoltaic panels, produced with colored cells suitable for areas subject to architectural and landscape limitations. This color is easily confused with facades, canopies and tiles, and can even be installed in historic centers. Its maximum power can reach 310 Wp. The downside of this type of panel is that it is much more expensive than a blue polycrystalline panel and therefore the investment is not cheaper.

What do you choose to install a monocrystalline panel type and when a polycrystalline panel type?

In less bright places, it is better to install polycrystalline panels because the sky is less clear, where a monocrystalline panel may be enough to produce enough energy to cover consumption.

Amorphous silicon panels.

In its simplest form, an amorphous silicon photovoltaic cell is constructed by depositing layers of silicon on a support material, typically glass.

Amorphous silicon panels have a lower efficiency than crystalline silicon panels, currently around 8-12% and therefore require, for the same power, a greater extension of the photovoltaic field.

Amorphous silicon panels take better advantage of the diffuse component of solar radiation. Less use of materials, therefore lower production costs.

This solution brings flexibility and versatility allowing the realization of photovoltaic cells in a variety of configurations.

Thin film photovoltaic panels.

Not all types of photovoltaic panels are made of silicon. Thin-film panels are for example made of a mixture of copper, indium, gallium and selenium or cadmium tellurium. Their characteristic is that they perform well even in diffused light conditions, or when they are not exactly facing the sun, and they can produce more when there are high temperatures. These types of panels have an average efficiency of 15-16% and require more space than mono and polycrystalline panels.

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