Winegrowers attracted to agrivoltaics in the face of climate uncertainties

"Every year, I lose 5 to 10% of my harvest because of scalding, the heat burns the grapes," explains David Moreau, 45, a cognac producer in Saint-André-de-Lidon, south of Saintes.

"In case of hail, by laying the panels flat, 70 to 80% of the vines are saved. And that gives me a 90% chance of being spared from frost," he adds.

Data provided by Sun'Agri, the agrivoltaic division of the Eiffage group which supplied and installed the 6.000 panels of the project, remotely adjustable to alternate shade and sun according to the needs of the plant, at a cost of four million euros.

Five meters below this vast metal structure, the winegrower planted his rows of Ugni Blanc and the agrivoltaic power plant was inaugurated at the beginning of May, a first in the department in the wine sector, while the cognac industry, in crisis, announced a vast uprooting plan.

Rent paid

The proceeds from the sale of electricity - "the equivalent of the consumption of 800 to 1.000 families per year", according to the company - go to an investor who pays a rent of 600 euros per year, over 30 years, to the farmer.

"The panels are controlled by Sun'Agri in real time using software," based on a model of plant growth and meteorological data recorded by sensors on the plot. "But the winegrower can take control, for example in the event of hail," emphasizes Boris Marchal, director of public affairs at Sun'Agri.

The company lists "around twenty" similar projects around the Mediterranean, in the Rhône Valley and in Nouvelle-Aquitaine. "Further north, the benefit of climate protection is not proven," says the manager.

Favored by the APER law, relating to the acceleration of the production of renewable energies, these systems are also the subject of numerous experiments, such as Vitivolt in Val-de-Loire or Vitisolar, launched by the National Research Institute for Agriculture, Food and the Environment (Inrae) in Villenave-d'Ornon, near Bordeaux - both until 2028.

In the Pyrénées-Orientales, the Nidolères estate is a pioneer with 4,5 hectares of vines planted under an agrivoltaic system since 2018. "Their feedback on yields is very positive," notes David Moreau, who plans his first harvest in 2029.

Landscape impact

The development of the sector is hampered by the regulations in force which, since 2002, have prohibited any coverage of vineyards under controlled designation of origin (AOC) or protected geographical indication (IGP) - representing 95% of national production.

But "it is possible to deviate from this by carrying out experiments," explains Christian Paly, president of the wines and spirits committee at the National Institute of Origin and Quality (Inao).

Some AOCs even prohibit agrivoltaics in their specifications, as the Côtes-du-Rhône appellation did in the autumn, due in particular to "landscape disfigurement".

The Cognac trade association will finalize its position based on the results of ongoing assessments of the "landscape, quality, economic, and regulatory" impact. In the meantime, the producer from Saint-André-de-Lidon knows he will only harvest "wine without a geographical indication."

According to the head of the Inao, "in a national strategy for adapting to climate change, we must not dismiss photovoltaics out of hand, provided that we experiment and regulate it."

The FNSEA, the dominant agricultural union, views the sector favorably. "It allows for the production of cheap electricity and visibly improves the quality" of production, says Olivier Dauger, FNSEA administrator and co-president of the France Agrivoltaism association.

"There is apprehension and internal debate within the AOC system because there is still no long-term data (...). People need to be reassured; there aren't going to be signs everywhere," he adds. Projections indicate that by 2050, this will cover 0,5% of French agricultural land, across all sectors.