A mosaic of microclimates: biodiversity outcomes and wildlife habitat potential in large-scale solar facilities.

The rapid global expansion of photovoltaic (PV) solar facilities, now comprising nearly 80% of the recent and projected growth of renewable electricity, represents one of the most significant land-use changes of the 21st century. While PV facilities are critical for decarbonising energy systems, their large spatial footprint and infrastructure fundamentally alter local abiotic conditions, with potential cascading effects on ecosystems and biodiversity. This review synthesises findings from 33 peer-reviewed publications across diverse climates and ecosystems, examining how large-scale solar facilities modify microclimates. Key environmental variables affected include temperature, humidity, wind speed, soil moisture, albedo, and photosynthetically active radiation. Generally, PV arrays create spatially heterogeneous microclimates: air temperatures are often elevated above panels, while soils beneath tend to be cooler, more stable, and retain more moisture due to shading. However, these patterns are not universal. Generalisations are limited by small sample sizes, variation in sensor placement, and differences in study design, so results may not apply to all PV facilities or biomes. The effects of PV arrays on microclimate are likely context dependent, varying with local climate, facility design, and ground-cover management. This review highlights the need for standardised microclimate research and reporting within solar facilities to understand environmental variability better across sites and regions. Integrating microclimate studies with ecological modelling and habitat suitability assessments will help researchers and land managers determine how species interact with environments within and around PV facilities. Leveraging such insights can guide facility design, inform habitat restoration, and support the sustainable development of solar energy.