Increasingly in demand in recent years, solar energy is positioned as one of the best solutions to achieve carbon neutrality.

While the enthusiasm it has aroused is very recent, its story is not. SirEnergies tells you the history of this energy source.

What is solar energy?

Solar energy is now one of most popular energy sources as part of the ecological transition. Its raw material is the sun.

Solar energy is therefore free and inexhaustible, insofar as the sun is not likely to disappear overnight. Moreover, it can be stored for later use.

The benefits of solar energy are multiple. This is what makes it a very popular solution. For example, unlike other alternative energy sources, it is clean, that is, it does not produce greenhouse gases.

How does solar energy work?

The mode of operation of solar energy depends on several factors, and more specifically on the production technique used. Today, there are three main categories of solar energy.

Solar thermal energy

This type of energy is one of the best known. It is produced from thermal solar panels which are generally placed on the roof of the house in order to capture the sun's heat.

More specifically, these panels are composed of heat transfer fluids (liquid or gas used to transfer heat from one location to another, usually in a heating or cooling system). When the latter are heated by the sun, they in turn heat the hot water tank. This is how solar thermal energy is obtained. It can be used in different ways: water heater, solar heating, stove...

Thermodynamic solar energy

A little rarer than the previous one, thermodynamic solar energy is produced from concentrated solar power plants. This equipment consists of several elements, including a solar electricity generator, and mirrors with heat transfer fluids.

Like solar thermal panels, mirrors are responsible for transforming the energy generated by The sun's rays in heat. The only difference is that the temperature here is much higher. It can be between 250 and 800°. The heat obtained is finally transformed into electrical energy, in particular by activating the turbogenerator.

Photovoltaic solar energy

Unlike other solar energies, which come mainly from heat, photovoltaic solar energy comes directly from solar radiation. Photovoltaic panels installed on the roof of your building capture the sun's photons, then the Convert to electric current.

These panels generally consist of a superposition of layers of cells, one of which is positively charged, while the other is negatively charged. When a photon passes through the layers, it creates an electrical voltage. All you have to do then is connect one wire to the positive terminal, and the other to the negative terminal to use the electricity generated. The operation of solar photovoltaic energy is therefore similar to that of a battery.

How is solar energy captured and stored?

Depending on the system used, solar energy is captured by photovoltaic panels, the thermal panels, or by the concentrated solar power plants.

In terms of its mode of storing, it is the same regardless of the technique used. In principle, solar energy is not in a position to guarantee the same performance every day. This one varies according to the amount of sunshine.

To store the electricity produced so that it can be used later, you need solar storage batteries. They are generally quite accessible. However, their cost depends on their storage capacity and the technology used.

When was solar energy discovered?

You may have only started hearing about solar power a few years ago. However, its use is not recent.

The origin of solar energy

In history, the very first use of solar energy may have been around 1500 BC, especially in the heart of ancient Egypt.

The Setjat, a kind of sundial, made it possible at the time to determine the time of day. Around 700 BC, man Learn to make a fire by concentrating sunlight.

For example, the Greeks were able to light the Olympic flame using an ingenious system. Thanks to the (fiery) mirrors, they were able to concentrate the sun's radiation at a specific point.

Solar energy would have even been used as a weapon of war during the III^E century BC. According to legend, Archimedes, thanks to the sun, repelled the Romans. He would have used brass shields to direct the sun's rays onto enemy ships to ignite.

When did solar energy become popular?

Solar energy has seen advances over the centuries. Even though its use dates back decades, it has only recently become popular.

In the 1800s, very few people used this energy source. Around the beginning of the 1900s, it became increasingly popular.

It's only around The end of the 1990sthe energy transition, which has become everyone's business.

The genesis of thermal energy

During the ancient period, humans understood early on that solar energy could be concentrated to produce high temperatures. It was only between the XVII^E And the XVIII^E century that the legend of Archimedes was truly experienced.

Passionate about optics, some physicists of this time carried out the construction of “large burning mirrors” that they used for a variety of purposes. Among others, they were Jean-Dominique Cassini (1625-1712), Edme Mariotte (1620-1684), François Villette (1621-1698). A few years later, it was the turn of Antoine Lavoisier (1743-1794) to use burning mirrors to melt metals.

The use of renewable solar energy for current needs will not be seen until the 18th century.^E century, thanks to the work of Horace-Bénédict de Saussure, physicist from Geneva. He was the first to present the concept of glazing placed on an absorber, which itself is placed on an insulated box. This is the principle of thermal sensors that continues to be used today. The first machines to convert solar energy were created in the 19th century.^E century.

This is the case, for example, of the famous Mouchot machine which was built by Augustin Bernard Mouchot in 1878. However, it was not until 1910 that the first solar water heaters were marketed.

The development of solar photovoltaic energy

The history of solar photovoltaic energy begins with the French physicist Edmond Becquerel in 1839. He was the first to point out The photovoltaic effect in an electrochemical cell.

His work was taken up and improved by Willoughby Smith in 1873. At that time, technology was not very advanced. We will have to wait for advances in quantum physics to relaunch the subject of solar photovoltaic energy.

Albert Einstein opened the wave in 1905, by deciphering The photoelectric effect. The principles of quantum physics will then be successively deciphered by several physicists such as Louis de Broglie, Werner Heisenberg or Erwin Schrödinger.

The first Photovoltaic cells to silicon will appear in the early 1950s, in particular thanks to the previous work of Gordon Teal and E. Buehler. In 1958, Vanguard 1 will be the first satellite to be equipped with a photovoltaic module of 100 MW and 100 cm². In 1964, the Japanese company Sharp developed the first large-scale photovoltaic module, operational for terrestrial applications.

What are the new developments in solar energy?

Every year, new techniques are invented to optimize the production, storage and use of solar energy.

The very latest one is The perovskite photovoltaic solar cell. Derived from the name of a Russian scientist, perovskite is a rare mineral that can be found in nature. However, its structure can be reproduced easily thanks to the combination of certain elements that are much more available.

Solar panels are generally made of silicon, which acts as a semiconductor in sensors. Perovskite can now be used as a substitute for silicon. The advantage is that it offers greater efficiency, is easy to produce and is more accessible in terms of cost.

Discovered only a few years ago, aerovoltaic panels are now widely used. This solution allows you to produce heating and electricity for your business and to carry out photovoltaic self-consumption.

Another evolution in the field of solar energy is Insolight technology. With this solution, each panel consists of several high level photovoltaic cells. The latter are placed under honeycomb lenses, allowing the sun's rays to be sent directly to the cells.

With this technology, you can have an efficiency of around 37% unlike a standard installation that only offers 18%. There are many other developments in solar energy such as solar tiles, solar optical panels, night panels, and many others.

Solar energy is not a contemporary invention. This renewable energy has existed for thousands of years, but has been perfected over the years thanks to technological advances. Despite its numerous advantages, it remains under the shadow of fossil energy whose disadvantages no longer need to be demonstrated.

To go further, do not hesitate to consult our article: Agrivoltaics: do solar and agricultural production mix?

Did you know that?

Recognizing the climate emergency, SirEnergies offers professionals and businesses the opportunity to limit the ecological impact in terms of energy.
We have made the choice to work with key players in solar photovoltaic to offer you support solutions dedicated to your photovoltaic self-consumption projects.
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