Effects of Agrivoltaics on the Microclimate in Horticulture

Abstract

Chilean agriculture must adapt to climate change as droughts are already affecting the country and water availability is expected to further decline. In this context, Agrivoltaics (AV) systems, that install photovoltaic (PV) panels over crops and thus provide shading and an altered microclimate could enhance the resilience of agriculture in semi-arid zones. We compare data measured under an AV system with a reference measurement to quantify the effects of AV on microclimate in horticulture in the Metropolitan Region of Santiago, Chile. Data on irradiation, air temperature, air humidity, and wind speed allow us to compute potential evapotranspiration (PET). We observe a reduction of Global Horizontal Irradiation (GHI) under the AV system of 42%. Mainly, as a result of the decreased GHI, we derive a diminution in PET of 31%, quantifying the potential to lower the water demand of crops and thus irrigation. Measured soil moisture is on average 29% higher under the AV system compared to the reference condition, hence validating PET computations. Also, we find a more moderate climate with slightly stabilized air temperature and lower soil temperatures. Our results give a glimpse of the effects of installing PV panels over horticulture crops concerning the challenges of Chilean agriculture. AV systems have the potential to increase water availability by lowering irrigation demand and protecting crops from the effects of extreme irradiation, such as sunburn and heat stress. Thus, AV could foster the transformation of agriculture towards sustainable production systems. The documented effects should be verified over longer periods with different crops to understand the impact of AV within seasonal and interannual climatical variation and the diversity of Chilean agriculture.