These installations, which are widespread in Japan and South Korea, are arousing growing enthusiasm in the world but reluctance from the agricultural world, which fears its consequences on land prices and farm productivity.
Fervent supporter, Christian Dupraz, 64, researcher in Montpellier at the National Research Institute for Agriculture and the Environment (INRAE) and former regional elected official EELV, assures on the contrary that it brings "real agricultural tools to the same as irrigation systems".
QUESTION: Why solar panels in the fields and not elsewhere?
ANSWER : "The idea came to us because we see, as agronomists, that plants only use a small fraction of the sun's radiation: they only capture roughly 30% of the sun's radiation.
So, on condition that light is left for the plants when they need it, there is a very large source of solar energy there without penalizing agriculture.
The simulations show that with less than 2% of the agricultural area used in France (30 million hectares), we could produce as much electricity as the current French nuclear fleet, so it is not anecdotal and in my opinion , it will be one of the major components of the energy mix of the future.
I insist: today, there are a million hectares devoted to biofuels and which are in competition with food production. If we replace that with agrivoltaic electricity, we will take up less surface area and it will be more efficient."
Q: Are these installations controversial?
A: “Today, there are technical debates about where it is authorized, how it is authorized and how it is avoided that it creates speculation on agricultural land.
The law is very interesting in that it prohibits photovoltaic panels on the ground on agricultural land, except for very long-term wasteland, ie agricultural land that has been abandoned for a very long time. Its very important.
The law only authorizes agrivoltaism, which is defined as a tool at the service of agricultural production to protect it against climate change.
It is almost imperceptible in the landscape. This is why there was no reason to restrict the establishment of agrivoltaic power plants to +acceleration zones+ defined by the mayors as the law does. It's the door open to all confusion."
Q: What is the agricultural interest of these installations?
A: "In a real agrivoltaic project, the culture produces as much as before or even better.
It is an activity that is both commercial (Editor's note: driven by manufacturers such as EDF Renewables, Engie Green, TSE, Valeco, Valorem, Solar Cloth, Urbasolar, Technique Solaire, etc.) and in favor of crops.
This allows up to 30% reduction in evapotranspiration under the panels depending on their density, orientation, steering, and protection against freezing by putting the panels horizontal at night. In summer, the drop in temperature on the ground can be as much as 20°C degrees.
You can grow fruit trees under the panels, with market gardening, and surround the hedge projects.
So it's really agricultural, just like hail nets, irrigation systems or shadehouses.
There are plenty of innovations: panels that move, bend, move, serve as hedges, adapt to greenhouses or open-field cultivation, or which only let through the photosynthesis wavelength and transform the rest into electricity.
There are already about fifty agrivoltaic power plants in France in service or under construction, and which generally cover two to three hectares. It remains an expensive installation, the law gives a boost, it is the very very beginning."