Shading grapevines with dynamic agrivoltaics address the challenge of early ripening and wine quality related with climate change

Abstract

Context and purpose of the study. Climate change accelerates grapevine’s phenology, advancing harvests by 2–3 weeks over the past 40 years negatively affecting wine style due to a lack of acidity and too much alcohol. Therefore, mitigation strategies are necessary to reduce heat and water stress, and preserve must quality. Sun’Agri with INRAE and CA84, have tested over six years (2019-2024) dynamic agrivoltaic system (DAV) to shade grapevines and address early ripening and wine quality challenges.

Material and Methods. A dynamic agrivoltaic system (DAV) was installed in 2019 over a ‘Grenache Noir’ vineyard in Piolenc, France, using 2 structures of 340 m2 with trackers above grapevine, oriented South-North with tilting opaque solar panels. 500 m2 in the same vineyard without panels were used as control. Two levels of shading (different steering policies at season scale) and two irrigation strategies (irrigated and non-irrigated in 2023 and 2024) were tested. Since 2019, microclimate, phenology, water status, yield determinants and berry quality have been evaluated. Since 2020, microvinifications in 100 l barrels were carried out. Wines were tested by an expert panel to characterize their sensorial profile and quantify their main descriptors (CATA method). For the 2023 wines a detailed analysis of aromas was conducted.

Results. Shading grapevines with dynamic agrivoltaics (DAV) improved the microclimate, reducing heat stress and preventing damage like defoliation or berry shrivelling. Veraison was delayed by 2–5 days, and harvest to 7 days. While yield remained similar across shading level, significant differences were observed across irrigation strategies. DAV increased acidity despite a similar level of sugar content in berries. Sensory analysis showed DAV wines were consistently fruitier, while control wines were more astringent. A difference in color was also noticed with more colorful wines for the control plots. The 2024 chemical analysis highlights how shading grapevines with dynamic agrivoltaics can influence wine profiles by increasing volatile compounds like 2-phényléthanol, isoamyl acetate, damascenone-beta, and terpenols, enhancing fruity aromas. Using dynamic agrivoltaics to control shading of grapevines when needed offers a strategy to delay ripening, improve berry quality and postpone harvesting. By modifying wine organoleptic profile, it helps winemakers achieve desired wine quality without suffering the effects of climate change.