Greenhouse-integrated photovoltaic modules: A systematic review of microclimate impacts and crop performance

• Solar radiation is the dominant microclimate effect of greenhouse-integrated PV systems • A PV roof coverage ratio of up to 25% is compatible with most greenhouse crops, causing no significant impairment to plant growth or fruit quality • Strawberry is the most shade-tolerant of the crops reviewed • Semi-transparent PV technologies (OPV, DSSC, a-Si) offer agronomically superior performance compared to conventional opaque modules at equivalent coverage ratios Greenhouses are considered an effective option for regulating cultivation conditions and increasing crop productivity. However, due to their high energy demand, increasing attention has recently been directed toward greenhouses integrated with photovoltaic (PV) units. This approach combines crop production and solar energy generation in the same land area, contributing to more efficient use of water, energy, and land resources. The aim of this review is to summarize recent scientific evidence on the effects of PV integration in greenhouses on the greenhouse microclimate, particularly solar radiation, temperature, and humidity, as well as on crop production, growth, and quality attributes. The results indicate that solar radiation is the microclimatic parameter most strongly affected beneath PV modules. Reductions in solar radiation vary according to PV type, coverage ratio, and orientation, and may exceed 40%. In contrast, temperature and relative humidity were generally reported to remain close to the ranges observed in conventional greenhouses. Regarding crop performance, PV coverage ratios up to 25% were generally associated with limited no significant effects on plant growth, yield, and quality. By contrast, coverage ratios between 50% and 100% were frequently associated with marked reductions in crop performance, although strawberry appeared relatively more tolerant to shade in some cases. Conventional opaque crystalline silicon PV systems offer high electrical efficiency but require careful design to avoid excessive shading, whereas semi-transparent thin-film PV systems provide greater flexibility in light management. Overall, these findings can support the future optimization of greenhouse PV technologies.