Vines Grown Under Solar Panels in Puglia Produced Much Heavier Grape Clusters
A University of Bari field study found shaded Primitivo vines grew longer shoots and bigger bunches in a hot, dry climate.
Grapevines grown beneath solar panels in southern Italy grew far more vigorously than vines in full sun, according to a study by researchers at the University of Bari discussed in an October 2026 PV Magazine Italia interview.
What the researchers found
The paper, "Agrivoltaics in Mediterranean viticulture: Impacts on physiology, yield and biodiversity," was published in *Scientia Horticulturae*. It was carried out at a community agrivoltaic vineyard in Laterza, in Puglia. Lead researcher Giuseppe Ferrara, of the university's Department of Soil, Plant and Food Sciences, discussed the results.
- Shoot length: about 116 cm in full sun versus roughly 268 to 274 cm in the shaded treatments
- Cluster weight: about 65 g in full sun versus about 165 g under the panels
- Sugar: 25.8 °Brix in full sun versus 22.9 °Brix under panels, with little change in acidity
- Plant diversity on the ground was significantly higher under the panels
- Air temperature was around 0.5 to 1 °C cooler
Why it may happen
Ferrara links the gains to cooler conditions that make photosynthesis more efficient. Lower sugar levels reflect slower ripening and perhaps extra water in the berries, which matters for winemakers.
Honest limits
Ferrara stresses the result applies to a hot, dry climate like Puglia's summer, and that agrivoltaics needs case-by-case evaluation. Another trial in Italy's Valpolicella found higher yields outside the panels. The vineyard was mostly rain-fed, and soil life was not yet studied, though the team plans to do so.
Still, the work adds evidence that farmland can host both food crops and clean electricity, a combination that could ease competition for land as solar expands.
