Where does the sun's energy come from?

We see the Sun every day and we benefit from the free energy it gives off every second that passes. However, we realize quite quickly that we do not know much about him.

Fortunately, researchers have spent a lot of time studying this unlimited source of heat and energy. Thanks to them, for example, we know where the energy released by the sun comes from.

SirEnergies explains to you where this energy from the Sun that is so dear to us comes from.

The Sun: what is it?

The Sun is a medium sized star, a sphere of gas whose Hydrogen is the main component. As you might have guessed, the temperature is very high on the Sun. Indeed, it would be 15 million degrees!

The Sun is the closest star to Earth, located 149.6 million kilometers from our planet. It is thus a huge nuclear reactor in which hydrogen nuclei fuse.

This phenomenon will produce a continuous chain reaction which will, in turn, produce helium nuclei and a slight loss of mass. It is the latter that will be converted into energy. It comes in the form of light and particles called neutrinos.

The Sun is therefore a sphere that is always active. It is its thermonuclear reaction which gives off the light and the solar wind that our planet benefits from.

Why is the sun shining?

The Sun is composed mainly Of hydrogen, an atomic element whose nucleus is reduced to one proton. When the cloud of stellar matter (hydrogen) that forms the Sun contracts under the effect of the pull of gravity, it will heat up, creating nuclear reactions. It is from this phenomenon that the sun's energy comes from.

The nuclear reaction, which is the source of solar energy, results from the fusion of two protons, wearing out Hydrogen as fuel. This will create what is called A deuterium nucleus.

This is a phenomenon that releases about 2 million electron volts. For this reaction to take place, however, protons or hydrogen nuclei must come into contact. However, this is only possible at very high temperatures, in excess of one million degrees (just that!).

Solar energy, a phenomenon similar to radioactivity

Solar energy comes from a phenomenon similar to radioactivity. In fact, the deuterium nucleus is composed of a proton and a neutron. You should know that the transformation of a proton into a neutron is only possible with the forces Nuclear that come from beta radioactivity, also called weak forces.

Without this radioactivity, this fusion reaction would be impossible, because the protons repel each other. Fortunately, each of the two protons can be transformed into a neutron.

During its transformation, the neutron will emit a particle called a W boson. In general, this particle is immediately reabsorbed, which means that the neutron will become a proton again.

However (and luckily for us), sometimes the W boson still finds time to disintegrate into a positron and a neutrino, which simply means that the neutron will no longer become a proton again. It can thus fuse with the other proton, which will give life to a deuterium nucleus.

The fusion reaction, at the origin of nuclei essential to life

The neutron and proton fusion reaction, called paramount, releases energy and heat, but not only that. Indeed, it also generates neutrons, which are essential for the formation of the various atoms that surround us. For example, deuterium neutrons are responsible for the formation of helium nuclei, carbon nuclei, and oxygen nuclei.

The Sun, an inexhaustible source of energy

The spark that is at the origin of this phenomenon that is the Sun, that is to say The fusion of hydrogen, is very rare and difficult to make. Indeed, rare are collisions between protons that end in fusion.

Since that spark, the Sun has been living at a slow pace, so it consumes its proton reserve very slowly. This explains the fact that it has shone for so long and will continue to shine for billions of years.

Every second, the Sun transforms 4 million tons of its mass into radiative energy. The latter still has to cross the various layers of the Sun (they are a total of 700,000 kilometers) before reaching its surface. The light released at the center of the Sun takes at least 100,000 years before reaching the Sun's surface.

When light hits the surface of the Sun, things change much more quickly! In fact, the Sun rays only take 8 minutes and 20 seconds to get to Earth.

The exploitation of solar energy

Solar energy, used by humans, is drawn directly from the sun's radiation. Researchers have developed techniques that make it possible to use and recover solar energy to transform it into electricity or energy.

It was in 1916 that energy was produced for the first time with A solar cell. Robert Andrews Millikan did this feat, but the energy obtained was insufficient.

Solar energy was only truly exploited during the 1970s. It was at this time that the photovoltaic panels were used for the first time in homes.

Today, solar radiation is a renewable energy source used by individuals, manufacturers, businesses and communities.

Is the sun going to go out someday?

According to researchers, the Sun has been shining for 4.5 billion years now and (good news!) it should shine again for 4 to 6 billion years. What could this extinction come from? The sun will no longer be able to shine when it has run out of hydrogen.

The Sun will simply collapse without the pressure of the radiation it emits, because it is the radiation it emits that counteracts the effect of the forces of gravity. However, neutrinos pass through the Sun much faster than light (in two seconds). So the sun still has a bright future ahead of it.

To go further, do not hesitate to read our article to know What makes solar energy green ?

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.
Click below for more information:

Self-consumption solution