Studies map microclimates beneath solar panels to help native vegetation thrive in the shadow of renewable energy

A University of Alberta study has uncovered how solar panels create unique microclimates that influence the growth of native vegetation under the panels. The research published in Ecological Engineering emphasizes the importance of native grasses for ecological benefits like soil stability, carbon storage, water infiltration, and pollinator habitats.

Native grasslands are rare ecosystems, making their restoration valuable. The study examined the effects of solar panels on seven seeded native grass species over two years at kīsikāw pīsim solar farm, a former cropland in the North Saskatchewan River valley, Edmonton.

Solar panels significantly alter the growing conditions underneath. In open spaces between panels, plants receive nearly 12 times more sunlight, and soil temperature is about 3.2°C warmer and 12% drier compared to shaded areas directly under the panels. Wetter, lower-lying areas experienced 68% more vegetation and nearly double the amount of grass.

Different plants had varying preferences around the panels, with sunny areas hosting more native grasses and invasive weeds, while some non-native grasses survived in both full sun and deep shade.

The findings suggest that solar farms can support the re-establishment of native grasses through strategic approaches such as choosing appropriate seed mixes with shade and drought tolerance, targeted weed control, and adjusting the design of solar farms by spacing rows farther apart or mounting panels higher. Integrating native grassland restoration into solar energy development is crucial for preserving plant biodiversity and resilience, contributing to sustainable solutions.