Everything you need to know about how a photovoltaic panel works

 Photovoltaic panels transform solar radiation into electricity. This energy is renewable and constitutes a major issue in the context of the energy transition. Do you want to lower your electricity bills? The use of solar collectors for self-consumption is the preferred solution. You can also resell all or part of the photovoltaic energy produced. The recipe allows you to amortize the installation cost. In 2017, globally, photovoltaic solar energy production represented 1.7% of electricity production. It could reach 16% in 2050 according to the International Energy Agency. Are you planning to produce green electricity at home and want to know everything about how a photovoltaic panel works? See what follows

How does a photovoltaic panel work?

Solar collectors are made up of photovoltaic cells. How does this device manage to produce electricity?

The photoelectric effect

Photovoltaic cells form the basis of the system. Most of these electronic components are made of silicon, a semiconductor material. They transform solar radiation into photovoltaic energy.

But how ?

Thanks to the photoelectric effect discovered by Antoine Becquerel in 1839 .

It is based on the reaction of semiconductor materials when they come into contact with solar radiation. When photons contained in sunlight strike the surface of photovoltaic panels, they transmit their energy to the electrons in the silicon. These then start moving. Which generates a direct electric current.

It must then be transformed into alternating current before being used in your home or integrating an electrical distribution network. This conversion is done using an inverter.

Also read: How many solar panels to power your house?

The peak kilowatt or kWp

This unit of measurement makes it possible to compare the performance of different types of photovoltaic panels. It is provided by the manufacturers and corresponds to the maximum power that a panel can produce when sunlight conditions are optimal.

Do not confuse it with kilowatt-hour or kWh. It represents the quantity of electricity produced by the photovoltaic panel during a given period of time.

How efficient are solar panels?

The performance of a photovoltaic panel depends on several factors.

Solar radiation

Not all regions are equal when it comes to solar radiation. It is useful to distinguish 3 types:

• Direct radiation is the most effective. The sun's rays hit straight on the photovoltaic panels.
• Radiation is indirect when the sun's rays must pass through obstacles such as clouds or pollution.
• The reflected radiation first hits a surface such as water or snow before being reflected back onto the solar panels.

The performance of photovoltaic panels depends on the quantity and quality of sunshine. The electricity production produced by a solar panel will not be the same depending on whether it is installed in the north or the south of France.

Inverters

The operation of a photovoltaic panel requires the presence of an inverter. It transforms the direct current produced by the photovoltaic panels into usable alternating current.

There are two types of inverters.

The central inverter takes care of all the solar panels. It must be placed as close as possible to your installation. This material is economical and should be favored when the photovoltaic panels benefit from homogeneous sunlight. But be careful, with the central inverter, when a panel is defective, the entire installation is shut down.

Microinverters support one or two photovoltaic panels and are housed directly behind them. They are indicated when the orientation of the panels is heterogeneous or when your installation is partially shaded. With miniature inverters, the device continues to operate even when one of the panels is defective. This system is more expensive than the previous one

The 3 types of photovoltaic panels

Solar panels differ in the quality of the silicon used to manufacture the photovoltaic cells.

The monocrystalline panel. Its cells are made of a single block of silicon. It is distinguished by its black color. It is the most expensive of the photovoltaic panels. It also produces the best yield between 16 and 24%.

The polycrystalline panel. You recognize it by its dark blue color. Its photovoltaic cells are made with several silicon crystals. Its yield is between 14 and 18%.

The amorphous panel. He can create electricity with artificial light. Light and inexpensive, its yield is between 5 and 7%. This low performance is due to the fact that its photovoltaic cells contain very little silicon. But thanks to its flexibility, it adapts to supports with a reduced surface area such as a calculator.

Where can photovoltaic panels be installed?

Do you want to install photovoltaic panels on your house? Did you know that the ideal condition in this case is to have a roof facing south, devoid of shade and inclined at 30°.

Is your home under construction? The installation of the panels is included in the building permit. For an existing structure, an authorization request must be submitted to the town hall.

As for installation methods, you have the choice between 3 techniques.

• The panels are placed on the frame. They are integrated into the roof and replace part of the tiles. This method of installation is rather expensive, but remains durable over time thanks to new waterproofing processes.
• The panels are installed on top of the roof. This method is the most common and costs less than the previous one.
• Do you have a large plot of land? In this case, it is possible to install the photovoltaic panels on the ground. This technique has some disadvantages such as the presence of visible cables for example.

What are the advantages of photovoltaic panels?

The mode of operation of a photovoltaic panel provides numerous advantages in terms of ecology and economy.

• You have renewable energy available to infinity.
• Greenhouse gas emissions are limited.
• In self-consumption, solar panels allow you to reduce your energy bills.
• The surplus electricity generated can be resold provided that your installation is connected to the network.
• The implementation of photovoltaic sensors is simple.
• The materials used are robust.
• It is possible to store the energy produced by your installation in a battery to compensate for irregular electricity production.

However, its use has certain disadvantages.

• Its recycling is not quite perfect.
• The budget required for installation remains high.
• The performance of the panels decreases over time