Solar energy production has been rapidly expanding in the Southeast; in Georgia alone, acreage has increased from under 500 to over 25,000 acres in the last decade. Agrivoltaics and ecovoltaics have emerged as strategies to ease land competition between Large-Scale Solar (LSS), agriculture, and natural resources. Agrivoltaic systems co-locate solar panels with row crops or livestock agriculture, thereby “stacking” the production of energy and agricultural products on the same land. LSS sites are typically seeded with Bahia and Bermuda grasses to control erosion while vegetation height is maintained by mechanical mowing. However, one of the most common and successful agrivoltaic applications is grazing livestock – typically sheep, which benefit from a high-protein diet, such as a legume. Rhizoma Perennial Peanut (RPP) is an emerging forage crop grown predominantly in southern areas with sandy soils and permissive winter temperatures. Most LSS are located in mid- and South Georgia where soils may have higher clay content. We set out to explore feasibility of RPP as a land cover under solar system in South Georgia. RPP ‘EcoTurf’ was planted between solar panels and outside the solar array. We implemented two experimental treatments: three seeding rates (100, 140, or 160 bushels/acre), and fertilization at planting or at mid-season. We measured canopy spread, leaf chlorophyll content and fluorescence. We also counted blooms and made aerial sweeps to assess arthropod abundance and diversity. In addition to being a potential grazing source, RPP matures well below the leading edge of the solar panels, thus eliminating the need for mowing even without livestock. If left uncut, RPP produces attractive yellow blooms which may serve as floral resources for pollinators and other beneficial insects. In this way, RPP can provide ecosystem services, including biodiversity and wildlife habitat, a potential win-win opportunity for LSS development and natural ecosystems in the Southeast USA. Given the selection of low growing ground cover that requires less frequent mowing (or no mowing), the implementation of RPP could also lead to lower inputs and reduced operation costs of the LSS in the long term.
