Large-Scale Solar Siting Research

Large-scale solar (LSS) siting refers to the decision-making processes and actions that determine the location and design of new LSS facilities. Also known as utility-scale or ground-mounted solar, LSS generally refers to projects greater than 1 megawatt (MW) in size.

The LSS siting process starts with the entity developing the project—a solar developer, a utility, or a municipality—identifying land that is suitable for installation. This site selection process requires the consideration of a wide variety of factors, including but not limited to a customer who will purchase the power, interconnection costs, transmission access, topography, land costs, zoning ordinances, wildlife and environmental impacts, and host community needs and priorities. Once a site has been selected, the developer typically leases or purchases the land, engages with the host community on project benefits and burdens, obtains permits, and often subcontracts with engineering and construction companies to design and build the facility. Developers must navigate different processes and requirements during the permitting processes based on the location of the proposed project.

Solar energy siting encompasses several of SETO’s other soft costs research topics, including solar energy cost and data analysisagrivoltaics, and solar energy, wildlife, and the environment

Why is Large-Scale Solar Siting Important?

According to the Solar Futures Study, ground-mounted solar is projected to require about 5.7 million acres of land by 2035 (0.3% of the contiguous U.S.), increasing to as much as 10 million acres by 2050 (0.5%). Key decisions during the siting, permitting, engineering, and construction of a solar installation determine the extent of the benefits and adverse impacts to local communities, ecosystems, and agricultural areas. 

Communities where solar projects are being considered frequently have questions about the likely benefits and burdens of the facility. Developers typically engage with members of host communities to understand local priorities and concerns and to identify opportunities for improved benefits if projects are developed. Local governments and the agencies with authority to permit the construction of facilities also frequently provide a platform for community engagement when they review permit applications or when they are considering future energy deployment within communities.   

LSS project developers incur significant costs to navigate siting and permitting processes. Prolonged development timelines, project cancellations, restrictive ordinances or bans on LSS facilities, and complex site configurations or designs can contribute to the soft costs, or non-hardware costs, of solar energy. 

The U.S. Department of Energy (DOE) Solar Energy Technologies Office (SETO) works alongside stakeholders, including solar developers, regulators, and host communities to identify strategies and tools that improve siting and permitting processes and outcomes. Learn more about SETO’s goals.

SETO Research in Large-Scale Solar Siting

SETO supports research to improve LSS siting processes and outcomes for host communities, wildlife, ecosystems, and solar developers. SETO has four categories of research related to LSS siting:

Social Benefits and Costs

SETO projects study community engagement strategies during the siting process, community perceptions of LSS projects, and economic benefits and impacts resulting from LSS development. 

  • Round 4 of SETO’s Solar Energy Evolution and Diffusion Studies (SEEDS4) aims to generate actionable insights that guide solar developers, landowners, community organizations, and other stakeholders to improve LSS siting processes and outcomes for host communities and the solar industry.
  • The Community-Centered Solar Development (CCSD) project led by Lawrence Berkeley National Laboratory is conducting research to understand concerns, benefits, and drawbacks of LSS, and supporting communities to improve their planning processes for hosting LSS projects.

Innovative Siting Solutions 

SETO research seeks to reduce land use conflicts for LSS siting through two main mechanisms: agrivoltaics (the co-location of solar and agriculture) and floating solar.

  • SETO’s Foundational Agrivoltaic Research for Megawatt Scale (FARMS) funding program studies how the co-location of agriculture and solar production on the same land can provide new economic opportunities to farmers, rural communities, and the solar industry. Projects are developing technologies, evaluating practices, and gathering foundational data to support future deployment of agrivoltaic systems.
  • The AquaPV Project led by Idaho National Laboratory provides foundational data and analyses on the technoeconomic potential for floating solar projects on U.S. reservoirs and estuaries. 

Environmental Benefits and Costs

SETO supports research to better understand how solar energy installations, wildlife, and ecosystems interact. Research topics include LSS interactions with birds, large mammals, native vegetation, water, and soil.

Foundational Data Collection and Analysis 

SETO research focuses on gathering data and developing analytical tools that are publicly accessible and can be applied to LSS siting and planning activities. 

  • The U.S. Photovoltaic Database, developed by U.S. Geological Survey and the National Renewable Energy Laboratory, provides the locations, array boundaries, and other characteristics of ground-mounted photovoltaic facilities with 1 MW of capacity or more. 
  • The National Renewable Energy Laboratory recently published an inventory of local LSS zoning ordinances, a tool that will inform discussions about local siting considerations. 

SETO Technical Assistance on Large-Scale Solar Siting

SETO supports programs that enable stakeholders to apply research findings and improve their familiarity and expertise to engage on LSS siting topics.

Learn more about the siting of large-scale renewable energy projectssoft costs research, other solar energy research in SETO, and view current and former funding programs.