And the wind? Where does it come from?
We may never have thought about it. The sun has a number of effects on our world, and one of them is the wind. Between 1% and 2% of the solar radiation absorbed by the planet ends up turned into wind. This is because the Earth's crust transfers a greater amount of solar energy to the air, causing it to warm, become less bulky, and expand. At the same time, the coldest and heaviest air - which comes from seas, rivers and oceans - is set in motion to take the place left by the warm air. These fluctuations produce moving air and wind is nothing but moving air.
Each mass of air that moves from areas of high atmospheric pressure to areas of lower pressure through speeds proportional to the pressure differences between both areas (the greater the difference, the stronger the wind blows) is considered wind.
And the sun? How is it transformed into electricity?
The sun's energy comes from sunlight and heat. To transform them into energy, semiconductor metal sheets are needed: photovoltaic cells.
These cells are coated with a transparent glass that allows radiation to pass through and minimises heat loss, and have one or more layers of a semiconductor material. Thanks to these elements, they can manage all that solar energy.
Increasingly, we can see solar panels on the roofs of houses and buildings. These panels are fully formed by these photovoltaic cells.
It is said to be expensive to install, but the data show that the purchase pays for itself, with savings of around 30% of consumption, which in the long term (25 years) means paying between EUR 20,000 and EUR 30,000 less, making it very valuable in the medium to long term. Another advantage is that they do not need much maintenance.
And how does a solar panel work?
Basically through the sun's rays. These are composed of photons that reach the photovoltaic cells of the plate, generating an electricity field between them and thus an electrical circuit. The more intense the light, the greater the flow of electricity.
Photovoltaic cells are responsible for converting sunlight into electricity in the form of direct current and with a graduation that varies between 380 and 800 volts. The result obtained can be improved using an inverter, which is responsible for transforming this energy into alternating current, which is what we use in our homes.
Finally, this alternating current passes through a meter that quantifies it and supplies it to the general electricity grid.