Can solar power provide more than clean energy?

Scientists from Argonne will study the soil around ground-mounted solar panels and develop a national soil database to better understand impacts on the ecosystem.

Climate change contributed to many deadly and costly disasters in recent years. As the U.S. looks to combat climate change, solar energy is increasingly seen as a large part of the answer. However, ground-mounted solar facilities occupy large areas of land. What will that land and soil be like after 30 or more years of use for generating clean power?

Researchers at the U.S. Department of Energy’s (DOE) Argonne National Laboratory are partnering with collaborators from other national laboratories and state, academic and private institutions to examine that question. DOE’s Solar Energy Technologies Office recently selected Argonne to lead a new project to better understand the changes that will occur in soils. The team will study what happens when past harmful practices such as pesticide use and annual tilling are stopped, the land under and around solar panels is allowed to rest and, in some cases, is planted with native grasses and wildflowers. The project is a part of the Deploying Solar with Wildlife and Ecosystem Services Benefits (SolWEB) funding program.

“If we hope to have an inhabitable planet for our kids and grandkids, we need to get serious about renewable energy sources — including solar power. As we take steps to combat the climate crisis, we must conduct more research to ensure that we can preserve and protect our ecosystems and wildlife as we transition to renewable energy,” said U.S. Senator Richard Durbin, Illinois. ​“I’m encouraged by DOE’s trust in Illinois’ world-class research facility, Argonne National Laboratory, and congratulate the Argonne scientists selected to lead this research.”

The three-year project will first standardize sampling, analytical and modeling methods for measuring changes in soil components such as carbon, nitrogen, phosphorus, certain metals and pesticides over time.

“I’m encouraged by DOE’s trust in Illinois’ world-class research facility, Argonne National Laboratory, and congratulate the Argonne scientists selected to lead this research.” — U.S. Senator Richard Durbin, Illinois

Then, with the support of industry partners, the methods will be tried out at solar facilities to establish baselines and demonstrate their effectiveness. Finally, a nationwide solar soils research database will be created and used to answer questions about the long-term impacts of these renewable power plants.

This research will provide a strong quantitative basis to inform the solar industry, regulators and stakeholders on the soil health and ecosystem service implications of solar energy development. Collectively, this project will inform national efforts to understand how solar energy can achieve climate goals while also meeting our nation’s social, ecological and energy needs.

“The expected acceleration of ground-mounted solar development presents an important opportunity for active land and vegetation management that can restore soil ecosystem services,” said Heidi M. Hartmann, environmental science and engineering leader at Argonne and project team lead. ​“This project will provide a solar soils database obtained with standardized protocols that will answer important questions about the ecosystem services provided by large-scale solar facilities. Project research will also provide information about the quantities and timeframes of carbon storage in soils at solar facilities, to further the goal of maximizing climate benefits within the solar industry.”

Besides providing ecosystem services, or benefits to humans, restoration projects could also benefit pollinators such as the endangered monarch butterfly and may build up and store carbon from decaying plant matter. Recent modeling by an Argonne-led team of researchers found the potential for managed solar sites to improve soil health and carbon sequestration. But restored prairies are not operational solar facilities, so it is important to get new and accurate data on whether solar facility soils will provide ecosystem services over time, and what types of vegetation management are most beneficial.

The project will also involve Midwestern tribes to help evaluate different methods for increasing ecosystem services when planning for new solar projects on tribal lands. If solar facilities can be shown to provide ecological benefits while also generating carbon-free energy, solar development may be more compatible with tribal goals.

Collaboration is central to this broad-scale national effort. Argonne is partnering with several universities, state agencies, private and nongovernmental organizations and other national labs in developing, testing and modeling methods for investigating soil ecosystem services at solar facilities. Project partners include:

• Brookhaven National Laboratory
• Columbia University
• Fermi National Accelerator Laboratory
• Midwest Tribal Energy Resources Association
• Minnesota Department of Commerce
• National Renewable Energy Laboratory
• Stantec
• The Soil Inventory Project
• University of Illinois Chicago
• University of Illinois Urbana-Champaign
• University of Minnesota

About the Solar Energy Technologies Office

The U.S. Department of Energy Solar Energy Technologies Office supports solar energy research, development, demonstration and technical assistance to improve the affordability, reliability and domestic benefit of solar technologies on the electric grid. Learn more at ener​gy​.gov/​e​e​r​e​/​solar.

Argonne National Laboratory seeks solutions to pressing national problems in science and technology. The nation’s first national laboratory, Argonne conducts leading-edge basic and applied scientific research in virtually every scientific discipline. Argonne researchers work closely with researchers from hundreds of companies, universities, and federal, state and municipal agencies to help them solve their specific problems, advance America’s scientific leadership and prepare the nation for a better future. With employees from more than 60 nations, Argonne is managed by UChicago Argonne, LLC for the U.S. Department of Energy’s Office of Science.

The U.S. Department of Energy’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit https://​ener​gy​.gov/​s​c​ience.