Most often installed on the ground or on metal supports, a solar field can be deployed by agricultural zone on land with an average surface area of 4 hectares. Still called solar power plants, the mission of solar fields is to transform the sun's radiation into electrical energy. This makes it possible to facilitate self-consumption.

Solar field: definition

A solar field is a set of photovoltaic panels installed on the ground or on a roof in order to transform the heat emitted by the sun's rays into energy. Often arranged in thongs, in parallel or in series, these panels are mounted on the same support and are connected to each other. They are then connected to a central inverter which is itself connected to the electrical network.

However, it is not enough to install a few plaques in your garden or on your roof to talk about a solar field. More precisely, the term “solar field” refers to an installation of photovoltaic panels that can cover several hundred square meters on the ground.

The solar field can also refer to an installation of solar modules on the roof of an industrial building, a hangar or a storage warehouse. The most appropriate term in this case is” Photovoltaic building ”. Still called photovoltaic farms, solar ground power plants are generally installed on large areas of polluted land, pastures, exhausted quarries or former industrial wastelands.

Three main solar power plants exist: photovoltaics, thermals and thermodynamics. The mode of operation therefore varies from one model to another.

Photovoltaic solar power plants

A solar photovoltaic power plant consists of:

• Photovoltaic panels usually equipped with silicon cells that channel solar radiation to produce a direct current that is then transmitted to an inverter;
• An inverter that transforms DC into alternating current;
• A transformer that optimizes the voltage of the current thus produced before injecting it into the distribution system;

Solar modules can be arranged on the ground or on the roof of an industrial building. In both cases, they are fixed to metal profiles whose panels are tilted and raised in a well-defined direction. The aim is to capture a maximum quantity of light radiation in order to optimize electricity production.

Solar thermal power plants

Solar thermal power plants are used to transform solar radiation into heat. This is injected into the domestic hot water production system or into the heating system. In other words, mirrored solar panels intercept solar radiation in order to generate heat of varying degrees of temperature. The heat thus obtained is sent to a boiler where it is used to supply the hot water production system or domestic heating.

The production of heat by a solar thermal power plant depends largely on sunlight. A complementary heating medium is therefore necessary to cover hot water needs during periods of low sunlight. There are various solar thermal power plants. It all depends on the technique of focusing the sun's rays.

Tower power plants

Tower power plants have adjustable mirrors on the ground that return solar radiation to a storage tank located at the top of the tower. They are more suitable for countries with a high level of sunshine, as the water could freeze in winter.

Cylindrical collector power plants

Power plants with cylindrical collectors, on the other hand, are composed of mirrors fixed on a horizontal axis. The latter follow The path of the sun's rays so as to concentrate them on a tube containing a heat transfer fluid. It is this fluid that will allow heat to be delivered to the power plant.

Parabolic collector power plants

As far as parabolic collector power plants are concerned, they are composed of parabolic cylindrical mirrors. These channel solar radiation onto the tube of the adjustable dishes which, in turn, contain mini-power plants.

Thermodynamic solar power plants

Like solar thermal power plants, thermodynamic solar power plants make it possible to generate heat. In this case, this heat can also be transformed into alternating current that can be stored for later use. Concretely, a thermodynamic solar power plant is composed of:

• Concentrated mirror solar panels. They capture solar radiation at a point that allows them to generate temperatures that can range from 400°C to 1000°C;
• A heat production system that consists of a heat transfer fluid, a receiver and a storage tank;
• Pressurized steam. It triggers a turbine that turns an alternator that, under action, produces alternating electric current.

The main advantage of a thermodynamic power plant is its ability to continue to produce electrical energy even during periods of low sunlight. This is possible thanks to its tank of storing.

Thermodynamic solar fields are more suitable for regions with strong sunlight (2,000 kWh/m²/year) in order to take maximum advantage of direct radiation. However, it is possible to install them in less sunny areas if the concentration sensors are replaced by vacuum tube sensors.

Photovoltaic farm: a major element in the energy transition

In 2019, The consumption of solar energy was 2.4% compared to total energy consumption in France. This represents an increase of 0.7% compared to 2017 when it was only 1.7%. Also in 2019, the parkland France's solar photovoltaic capacity has exceeded 10 GW with Occitanie, Nouvelle-Aquitaine and Provence-Alpes-Côte d'Azur as the main suppliers.

As far as solar power plants on the ground or on the roof are concerned, their connected capacity grew by 197% between 2014 and 2020. Self-consumption rooftop solar installations represent only 64% of this growth. We therefore deduce that it is the solar fields of significant size that are the main actors in the development of the sector.

For the energy transition, public authorities clearly favor solar energy, more precisely solar photovoltaic. Indeed, photovoltaic power plants are ideal for carrying out large-scale projects, especially thanks to solar farms.

In addition, solar photovoltaic is also very competitive in terms of price. The cost of solar energy production has, in fact, declined by around 5% between 2020 and 2021. Solar farms also make it possible to offer prices similar to those of the traditional energy market.

If solar fields are becoming more and more numerous in France, you should know that it is quite possible to install a solar power plant in self-consumption. This solution can allow farmers, private owners and manufacturers to produce their own electricity and possibly sell the surplus without having to buy more money.

Do not hesitate to read our article” What makes solar energy green? ” to go further.

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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Self-consumption solution