Minimizing environmental impacts of solar farms: a review of current science on landscape hydrology and guidance on stormwater management

Abstract

As solar energy becomes an increasingly cheap source of renewable energy, major utility-scale ground solar panel installations, often called ‘solar farms,’ are rapidly growing. With these solar farms often covering hundreds of acres, there is potential for impacts on natural hydrologic processes, including runoff generation and erosion. Here we review the current state of scientific research on hydrology and water quality impacts of solar farms, as well as management recommendations for minimizing any impacts. The limited field measurements indicate redistribution of soil moisture around solar farms, but net impacts on runoff and erosion are less clear. Research focused on coupling solar farms with agriculture as ‘agrivoltaics’ demonstrates reduced evaporative water losses and associated crop stress. With regards to land and stormwater management associated with solar farms, most US states currently do not have solar farm-specific recommendations and instead defer to standard stormwater management permits and guidance. In states with solar farm-specific guidance, typical recommendations include minimizing construction-related compaction, ensuring high cover of perennial vegetation with minimal maintenance, and designing with pervious space between solar panel rows to promote infiltration of any runoff; in some cases, structural stormwater management like infiltration basins may be required. In general, solar farms can be designed to minimize the impact on landscape ecohydrological processes, but more research is needed to determine whether current recommendations are adequate. In particular, there is a need for more field research on less ideal sites such as those with higher slopes.

Solar energy development on farmland: Three prevalent perspectives of conflict, synergy and compromise in the United States

“…These examples of best practices are supposed to ensure land can return to agricultural use (see also Byrne et al [66]). As there is only a small but growing body of research on the impacts solar energy development on farmland, it is unclear how development will ultimately effect soil health and future farm viability [22,67]. Moreover, even if this land could ecologically return to agriculture after a solar lease, this does not inherently contend with the institutional, economic, and sociocultural interests that would seek to keep it in solar [68].…”

Effect of Solar Farms on Soil Erosion in Hilly Environments: A Modeling Study from the Perspective of Hydrological Connectivity

“…When evaluating the potential to co-locate vegetation with solar infrastructure, the redistribution of soil moisture by PVs-which could potentially be used in concert with planting strategies to maximize plant growth or minimize soil erosion-should also be considered (Choi et al, 2020). Furthermore, there is always a need for more field research on less ideal sites such as those with steeper slopes, greater gully density, and more loessy soils (Yavari et al, 2022). It is also recommended that erosion and silt management be considered carefully and monitored regularly in these hilly environments (Dhar et al, 2020;Phalane, 2021).…”

Landscape Protection around the Pobiedziska Solar Park

“…Traffic routes are used along with intensive roadside vegetation to conceal the plant (Coffey, 2019). A method of high cover with perennial vegetation with minimal maintenance and the planning with permeable space between the rows of solar collectors was also described (Yavari et al, 2022). The construction of walls planted with trees and shrubs outside a plant (Community & Environmental Defense Services, 2022) is also used to hide large logistics facilities (Szumigała and Urbański, 2017).…”