The rapid expansion of utility-scale solar energy (USSE) development presents a significant challenge to achieving renewable energy goals while minimizing impacts on land use and wildlife. Current USSE siting practices prioritize efficient and cost-effective development strategies that do not adequately consider ecological impacts. This problem necessitates the development of ecologically friendly siting and facility arrangement strategies that minimize the effects of solar development on ecosystems and wildlife while promoting sustainable land use practices. However, the best management practices needed to achieve these objectives are still quite ambiguous, with minimal research conducted to quantify wildlife impacts and provide clear guidelines for policy implementation.
Distributed solar generation (DSG) presents an alternative development strategy, generating electricity close to demand centers using smaller, localized solar arrangements. Community solar, a specific form of DSG, exemplifies this decentralized approach by allowing multiple community members to collectively benefit from a shared solar installation, expanding access to clean energy while reducing land use impacts. In partnership with The Nature Conservancy and Highline Renewables, our research analyzes the known implications of USSE, the potential for DSG to improve habitat connectivity, and the state policies enabling innovative community solar siting practices. This report seeks to inform researchers, policymakers, and solar developers of policy frameworks and development practices that prioritize sustainable solar development.
Chapter 1 conducts a literature review on the known ecological impacts of USSE development, informing ecologists about and encouraging solar developers to employ low-impact siting strategies. Chapter 2 performs a novel, standalone geospatial analysis demonstrating how various solar facility arrangements and siting locations impact bobcat (Lynx rufus) connectivity. This analysis can help developers make informed decisions regarding solar facility placement and reinforces the need for policy frameworks that enable DSG. Next, in Chapter 3, we review current and emerging state community solar markets and provide recommendations to policymakers for designing future policies. Finally, in Chapter 4, we examine the role of agrivoltaics, the integration of solar generation with agricultural activities, as a strategy for developers to reduce solar facility land use impacts.
Our Chapter 1 literature review found that USSE facilities cause direct mortality to aquatic insects, birds, and bats while altering the movement and connectivity of ground-dwelling animals such as Pronghorn (Antilocapra americana) and Florida Panthers (Puma concolor). However, significant knowledge gaps exist in understanding these impacts—notably, the lack of Before-After-Control-Impact (BACI) studies and the limited geographic scope of research. Nearly 50% of the existing U.S. research has been conducted in the desert southwest, severely limiting the ability to extrapolate findings to the broader U.S. Wildlife-friendly fencing and vegetation management can help maintain suitable habitat; however, these solutions must be studied in other regions to assess their effectiveness.
The geospatial analysis conducted in Chapter 2 reveals that both siting practices and spatial arrangement of solar facilities greatly impact species movement across a landscape. By analyzing how the predicted movement patterns of bobcats in southeast Ohio responded to both a USSE development in Dixon Run and the theoretical redistribution of Dixon Run’s generation capacity, we found that by redistributing capacity across the landscape, impacts on bobcat movement are reduced. However, a sensitivity analysis revealed that the locations of the distributed solar were in areas already deemed poor habitat for bobcats. That said, it is important to note that relocation of a USSE facility the size of Dixon Run to the areas considered poor bobcat habitat was practically impossible. Small, localized installations were the only way to build in these areas.
Our policy analysis reveals significant variation among individual state community solar markets in the size of allowable projects, subscriber composition, and siting practices they encourage. Maryland and Ohio demonstrate different approaches to community solar policy, with Maryland emphasizing reducing barriers to low and moderate-income (LMI) participation, while Ohio promotes solar development on distressed sites and brownfields. Notably, state community solar markets often lack specific incentives that promote low-impact siting practices that minimize the solar facility’s impact on the local habitat. To improve future community solar legislation, policymakers should offer grants, tax credits, and other financial incentives that prioritize the preservation of existing topsoil and vegetation, site away from ecologically sensitive areas, and support innovative land use practices, including agrivoltaics.
Implementing agrivoltaics offers a promising solution to reducing the siting impacts of USSE facilities and the competing land demands for agricultural production and solar development. The literature reviewed demonstrates that agrivoltaic systems can benefit agricultural productivity, land use efficiency, panel efficiency, and livestock and ecosystem health. Agrivoltaic systems offer the greatest benefits under specific conditions, specifically hot and dry climates, where the shading provided by panels mitigates the effects of excessive heat and water stress on crop productivity and livestock well being. However, the efficacy of agrivoltaic systems can vary and is contingent upon various factors such as shading distribution, crop sensitivity, and environmental conditions. Future research into agrivoltaics should focus on optimizing system design, evaluating financial performance, and fostering landowner engagement to ensure the successful implementation of this innovative approach to land use.
