From Coal to Critical Minerals
The Prairie Research Institute (PRI) at the University of Illinois Urbana-Champaign (U. of I.) conducts work at the nexus of scientific research and industrial application, anchoring the narrative of the nation’s energy story. At the heart of this endeavor is the Illinois Basin, a massive geologic structure underlying roughly 70% of Illinois, with subsurface layers that hold a wealth of traditional energy resources and serve as a foundation for innovative environmental and energy solutions.
This dynamic interplay of past and future sets the stage for PRI’s role in a transformative era, and the Illinois Basin is a focal point of America’s energy future being shaped today.
Coal’s energy impact on Illinois
Coal has long been a staple of Illinois’ energy landscape, with coal-bearing Pennsylvanian rocks covering nearly 65 percent of Illinois, appearing in 86 of the state’s 102 counties. As of 1973, 46 mines were operating in the state, producing over 61 million tons of coal. However, Federal Clean Air Act (CAA) regulations, particularly the amendments of 1990, significantly impacted Illinois coal production. These regulations aimed to reduce sulfur dioxide emissions, making the removal of sulfur from Illinois coal costly and less economical compared to low-sulfur coal from the western United States. Major declines in Illinois coal production are attributed to competition from cleaner energy sources like natural gas and changing government policies. Still, Illinois was the 4th largest producer of coal in the United States in 2022 with 38 million tons produced.
Oil’s own energy story
Oil, another traditional resource, has seen its own peaks and troughs in production. Major oil production in Illinois began in 1905, and from 1907 through 1912, the basin was the third-most productive area in the United States. Oil production peaked in 1908 at 34 million barrels per year and then declined steadily. There were subsequent increases in production due to new exploration and waterflooding of old reservoirs, especially in the 1950s. Today, Illinois has more than 36,000 oil and gas wells and produces about 7 million barrels of crude oil annually.
A new frontier of renewable energy
Traditional sources of energy have been transitioning to more sustainable alternatives, and PRI has been at the forefront of technology development.
A groundbreaking project at the U. of I. led by PRI’s Illinois State Geological Survey (ISGS) tapped into a power source as old as the Earth itself: geothermal energy. This form of energy harnesses heat stored beneath the Earth’s surface, offering a stable, low-carbon alternative to traditional energy sources. Solar and wind energy are important but intermittent renewable sources. Geothermal energy is constant, making it essential in a portfolio of renewable energies.
ISGS evaluated the feasibility of establishing a geothermal energy system at the U. of I. to reach the university’s goal of achieving net-zero carbon emissions by 2050. Through that project, a comprehensive assessment of the basin’s geological, hydrological, and thermal characteristics has paved the way for broader applications of deep direct-use technologies, not just in Illinois, but across the U.S.
In 2023, ISGS began working on major projects as part of the Federal Geothermal Partnerships (FedGeo) initiative. The FedGeo initiative aims to replace existing heating and cooling systems and expand geothermal use at military installations and federal sites, the largest energy users in the nation. Converting federal sites to geothermal systems would significantly decrease carbon emissions and increase resilience and energy security. The first sites for the FedGeo projects are two U.S. Department of Defense installations: the U.S. Military Academy at West Point in New York and the U.S. Army Garrison Detroit Arsenal in Michigan. With these forward-looking projects, ISGS is helping to develop larger-scale demonstrations and procedural guidelines for broad geothermal deployment.
The Illinois Basin, with its unique geological features, is an ideal location not only for exploring geothermal potential but also for its vast potential to help in efforts to decarbonize energy systems.
CCUS – Carbon Capture, Utilization, and Storage
PRI has been researching carbon management options at local to regional scales for more than two decades. Expertise at ISGS and the Illinois Sustainable Technology Center (ISTC) includes carbon dioxide mitigation, removal through direct air capture, carbon utilization, and commercial-scale carbon storage. PRI’s extensive portfolio of projects showcases a comprehensive strategy that has positioned the institute as a national and international leader in carbon neutrality and sustainable energy practices.
In point source capture, ISTC leads the world’s largest capture pilot at City Water, Light & Power (CWLP) in Springfield, Illinois. Here, a 10-megawatt (MW) Linde-BASF post-combustion capture system is set to capture over 90% of carbon dioxide (CO2) emissions. CWLP also houses a pioneering 200 MW project that combines carbon capture with algae-based utilization, transport, and storage, supported by a $2.5 million US Department of Energy (DOE) grant.
The Prairie State Generating Company in Marissa, Illinois, is home to the world’s largest carbon capture front-end engineering and design (FEED) study, where an 816 MW Mitsubishi Heavy Industries system could capture 8.5 million tons of CO2 annually. Similarly, the University of Illinois’ Abbott Power Plant in Champaign and Holcim’s Ste. Genevieve Cement Plant in Missouri are significant players in ISTC’s carbon capture projects, which use advanced technologies to absorb CO2 from flue gas.
Recognized for its carbon capture expertise, PRI has been selected by the U.S. DOE Office of Fossil Energy and Carbon Management to lead feasibility studies for three regional direct air capture (DAC) hubs in Colorado, Florida, and Illinois. These hubs will focus on capturing CO2 from the atmosphere and storing it in geological formations or using it in industrial processes. DAC is crucial for reducing emissions from sectors like aviation and shipping and addressing legacy CO2 in the atmosphere.
The Illinois Basin Regional DAC Hub aims to promote technologies that capture atmospheric CO2 for storage in the Illinois Basin. The Colorado and Florida Regional DAC Hubs will also focus on capturing and storing atmospheric CO2, with each hub targeting the removal of at least 50,000 metric tons of CO2 per year.
The institute also leads a project with Climeworks technology for the first commercial-scale DAC + carbon storage (DAC+S) system in the United States, targeting the annual removal of 100,000 tons of CO2 from the atmosphere. Other collaborations, like the development of a DAC system at U.S. Steel’s Gary Works Plant in Indiana, plan to capture CO2 and use it in concrete, creating a circular carbon economy.
Once CO2 is either captured from emissions or removed from the atmosphere, if it isn’t used as a feedstock or construction material, it must be permanently stored. ISGS’ long history in geological research, dating back to the 1850s, has laid the foundation for its expertise in carbon storage research innovation. For over 20 years, ISGS has investigated the deep subsurface to characterize potential carbon storage sites.
Inside the Illinois Basin, the Mt. Simon Sandstone, at a depth of 6,000 to 7,000 feet, was used for the pioneering Illinois Basin-Decatur Project, which captured and injected 1 million metric tons of CO2 at the Archer Daniels Midland (ADM) Company facility in Decatur, Illinois. This project was the result of a collaborative team of more than 10 organizations and involved extensive site characterization, regulatory engagement, site planning, infrastructure development, and subsurface monitoring from 2007 to 2021. The first-of-a-kind project ultimately demonstrated effective and safe geological storage of CO2 at a near-commercial scale and has hosted over 1,000 visitors from 30 countries who came to do research or learn about the site.
Building on IBDP’s successes, the Illinois Industrial Carbon Capture and Storage (ICCS) Project achieved commercial-scale operations, capable of storing up to 3,000 tons of CO2 per day. As of late 2023, a total of 4.5 million metric tons of CO2 have been stored at this site, demonstrating longer-term scalability. Currently, ISGS leads numerous U.S. DOE Carbon Storage Assurance Facility Enterprise (CarbonSAFE) projects that are focused on reducing technical risks and costs associated with large-scale carbon storage. Additional storage formations are being evaluated, and the CarbonSAFE program is scaling up the deployment of carbon storage to help meet broad emissions reduction targets, for example, NetZero by 2050. The Basin continues to be a focus for carbon sequestration as many other projects also are evaluating storage potential at numerous sites.
In 2022, PRI took a pivotal step under Public Act 102-0341, to provide a comprehensive study to assess the viability, challenges, and prospects of carbon capture, utilization, and storage (CCUS) in Illinois. The study’s primary objective was to provide objective, science-based research while incorporating perspectives from environmental, regulatory, and energy sectors to assist Illinois policymakers in comprehending the role of CCUS in achieving the state’s emission targets. The report addresses key areas: the status of carbon management technologies in Illinois, opportunities and challenges for underground CO2 storage, stakeholder concerns, and policy options to address these challenges.
PRI is a vital contributor to the pursuit of sustainable and climate-friendly energy practices on regional to international stages. ISGS has advanced the understanding and practical implementation of CCUS by bringing the experiences of the Illinois Basin by helping to write international CCS standards as part of the International Standards Organization Technical Committee 265 on carbon capture, transportation, and storage. This involvement underscores ISGS’ commitment to shaping global best practices that align with existing national policies for widespread CCS deployment. Where policies have not yet been established, the ISO standards are available to facilitate the safety, environmental integrity, and effectiveness of CCS deployment worldwide.
Future energy management
One resource that Illinois does not contain is significant amounts of naturally occurring gas that can be used for electricity generation and heating. For that, Illinois relies significantly on natural gas transported to the state via interstate pipelines and stored below the ground in geologic formations until it is needed. There are currently 25 natural gas storage facilities located across the state that help meet the seasonal energy demands, especially in population centers like the Chicago metropolitan region. The PRI Natural Gas Working Group assisted stakeholders by assessing natural gas storage activities in Illinois related to natural resource characterization, management, and protection issues.
A fundamental role of PRI is to provide clear, scientifically accurate information to inform natural resources management decisions. That role will continue as PRI explores how to find sustainable and long-term energy solutions.
In recent years, the Illinois Basin has been a test site for new technologies aimed at storing compressed air and releasing it to generate electricity. Another promising approach is to use hydrogen as a high-energy content fuel that can be produced with low or zero greenhouse gas emissions from water and other chemicals. Creating hydrogen during periods of energy surplus and storing it underground is one long-duration, low-emission, energy storage option that can balance supply and demand for an entire electric grid. In the U.S., existing underground gas storage (UGS) facilities are a logical first place to consider subsurface hydrogen storage, because their geology has proven favorable for storage. And while Illinois has the largest amount (10%) of the nation’s natural gas storage capacity, new detailed assessments will be needed to verify their suitability for hydrogen storage. These needs motivate research to explore the technical feasibility of underground hydrogen storage. Safely leveraging even part of existing UGS infrastructure could provide major advantages to establishing future energy system infrastructure and reduce the need for new hydrogen storage facilities.
The push for a cleaner, more sustainable future has cast a spotlight on critical minerals and rare earth elements (REEs), crucial for advanced technologies that are central to national defense, transportation, and renewable energy infrastructure. The United States’ heavy reliance on imports for these raw materials, often from geopolitically unstable sources, has highlighted the need for domestic production. To address this, the U.S. Geological Survey (USGS) has designated over 50 elements and compounds as “critical minerals.” PRI’s wealth of expertise and resources places it at the center of this critical quest, particularly through initiatives like the Illinois Basin carbon ore, rare earth, and critical minerals (CORE-CM) and the Earth Mapping Resources Initiative (Earth MRI).
The CORE-CM initiative, targeting the Illinois Basin, stands out for its strategic evaluation of critical elements within coal and related byproducts. This comprehensive assessment encompasses not just mining and separation technologies, but also environmental justice, workforce development, and innovation. The aim is to kickstart an economy around these strategic elements, lessening the United States’ dependence on foreign sources of mineral resources and fostering a sustainable domestic supply chain.
Meanwhile, Earth MRI is revolutionizing our understanding of critical minerals’ domestic distribution. The initiative, a collaborative effort involving the USGS, state geological surveys, and other partners, is committed to expanding our geological knowledge and pinpointing potential domestic sources of these commodities. ISGS, a leader in Earth MRI, is conducting regional geochemical reconnaissance and geophysical surveys. Its work includes investigating areas like the Illinois-Kentucky Fluorspar District and the Wauboukigou Igneous Province, rich in REEs and other critical minerals.
PRI’s comprehensive research abilities, combined with its extensive background in geological and environmental studies, make it particularly well-suited for these projects. The Institute’s capabilities in geochemical analysis, geological mapping, and environmental assessment dovetail with the goals of CORE-CM and Earth MRI. Moreover, the Institute’s history of collaboration with federal and state entities and its capacity to mobilize interdisciplinary teams to bolster its role in these crucial initiatives.
The work undertaken by PRI in CORE-CM and Earth MRI is vital for the global transition to green energy and decarbonization. These initiatives contribute to national security and economic stability by enhancing the domestic production and research of critical minerals and REEs. They also mark steps towards a self-reliant, sustainable green future. With its expertise and leadership, PRI is a pivotal player in the United States’ journey towards a robust critical minerals economy.
Navigating the water–energy nexus
The interdependency of water and energy is a fundamental aspect of energy production and electricity generation, as water is indispensable throughout these processes, and energy is crucial for the treatment and delivery of water. This relationship was central to ISTC’s initiative when they embarked on designing a carbon capture system for Prairie State Generating Company (PSGC). A sustainable water source was paramount to avoid jeopardizing delicate ecosystems, local economies, and the water supplies of surrounding communities.
The expertise needed for this intricate task was found within PRI‘s Illinois State Water Survey, particularly its Watershed Science team led by State Hydrologist Laura Keefer. Hydrologists Jason Zhang and Elias Getahun, with a focus on surface water supply, availability, and hydrologic modeling, joined by postdoctoral researchers Guangping Qie and Andres Felipe Prada Sepulveda, who provided climate and hydrologic model results, were integral to the solution.
Zhang further highlighted the misconception of water abundance due to its proximity to the Mississippi River and Lake Michigan, cautioning against overlooking the risks associated with water supply due to its uneven distribution.
ISWS performed a water availability analysis for PSGC, which sources its water from the Kaskaskia River system, including the significant Lake Shelbyville and Carlyle Lake. Despite this, the team recognized that the Kaskaskia’s supply might not always meet the carbon capture system’s needs, especially during extreme droughts.
ISWS’ forward-thinking approach involved merging hydrologic and climate models to forecast up to the year 2100. These models predict increased variability in hydrological conditions, with drier summers and falls potentially leading to lower flows in the Kaskaskia system, despite an expected increase in average annual precipitation. This could present a serious challenge during summers when energy demand is at its highest.
The proposed solution was a storage pond to accumulate excess water during wet seasons, providing a buffer during low river flow. Analysis indicated that the pond could sustain the carbon capture system for 26 days.
The importance of water in CCS processes cannot be overstated, as it is extensively used for cooling, particularly in power generation facilities, but also in other processes such as boiler operation and solvent regeneration during CO2 capture. With the majority of power plants relying on surface and groundwater, which also serve agricultural and municipal needs, the management of these water resources is critical.
The global significance of this project lies in its pioneering approach to integrating water resource management with carbon capture technologies. As nations worldwide strive to mitigate climate change impacts and secure energy supplies, the innovative strategies developed at the Prairie State Generating Company’s Energy Campus set a precedent. The project not only addresses immediate local needs but also offers a model for sustainable water use in energy production, a critical consideration for countries seeking to balance ecological preservation with their energy and climate objectives. This project contributes to a global discourse on sustainable development, showcasing how integrated resource management can support the larger goal of a resilient and environmentally responsible energy future.
PRI’s research is critical in meeting the clean and sustainable energy needs of a globally connected world. By connecting the rich energy history of the Illinois Basin with cutting-edge technology and research, PRI is not just responding to energy demands but also leading the way toward a resilient and environmentally conscious future
The Institute’s initiatives in carbon capture, utilization, and storage, along with its advancements in renewable energy and critical mineral exploration, address the immediate needs of Illinois while also addressing global concerns by contributing to the reduction of carbon emissions, the diversification of energy sources, and the stabilization of supply chains for essential materials.
As the world seeks to balance economic growth with environmental preservation, the significance of PRI research lies not only in its scientific achievements but also in its ability to inform policy, guide industrial practices, and foster international standards that will sustain communities across the globe. In this transformative era, PRI is instrumental in shaping a sustainable energy economy for generations to come.