Learn more about how solar energy works

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Solar energy is the energy obtained through the light and heat emitted by the Sun. It can be used in photovoltaic or thermal form, generating electric and thermal energy, respectively. Considered a clean energy source, solar energy is one of the most promising alternative sources to obtain energy.

But how does solar energy work? Sunlight can be captured through several technologies, such as photovoltaic panels, heliothermic plants and solar heaters, for example. So when this light is captured, it is immediately converted into energy:

Photovoltaic solar energy

Photovoltaic solar energy is the direct conversion of solar radiation into electrical energy. This conversion is performed by so-called photovoltaic cells, composed of semiconductor material, usually silicon. When the sunlight falls on the cells, it causes the electrons of the conductive material to move, transporting them through this material until they are captured by an electric field (formed by a potential difference between the semiconductors). This way, electricity is generated.

Heliothermic solar energy

In the heliothermic system, solar panels are used (mirrors, collectors, heliostats), which reflect the sunlight, concentrating it in a single point where there is a receiver. This receiver is formed by a liquid, which in turn is heated by sunlight reflected on the panels. This liquid is responsible for storing heat, heating the water and thus producing steam that powers the turbines in the plants, activating generators that produce electricity.

Despite the growth in the use of solar energy in recent years, this form of energy represents only 1.3% of the electrical energy generated in the world. China stands out in the ranking of countries that invest in this sector, representing about 26% of the world’s solar energy installations.