The U.S. Department of Energy (DOE) has awarded $25 million to a three-year project led by the Prairie Research Institute that will design a next-generation power plant in Springfield, Illinois. The innovative plant design combines multiple techniques to both reduce emissions and capture and re-use carbon dioxide.
“With this project, we’re bringing together different pieces of the sustainable energy puzzle,” said Kevin OBrien, who is principal investigator of this project and leads the Illinois Sustainable Technology Center (ISTC) and Illinois State Water Survey (ISWS). “PRI’s scientists have been advancing emissions reduction, carbon capture, and carbon utilization, and this gives us an opportunity to combine all of our expertise and experience in these areas to deliver greater impact.”
The project (Front-End Engineering Design Study for Hybrid Gas Turbine and USC Coal Boiler (HGCC) Concept Plant with Post Combustion Carbon Capture and Energy Storage System at City, Water, Light and Power Plant) is part of DOE’s Coal FIRST (Flexible, Innovative, Resilient, Small, Transformative) initiative, which aims to spur innovation in coal-fired plants. While renewable energy sources, like solar and wind, account for an increasing proportion of U.S. electricity generation, these sources are variable; coal provides a stable source of power, ensuring that consumer demand can be met consistently.
Components of the design proposed by PRI scientists and their collaborators include:
- A 270-megawatt ultra-supercritical coal boiler subsystem
- An 87-megawatt natural gas combustion turbine generator subsystem
- A 50-megawatt energy storage subsystem
- A post-combustion carbon dioxide (CO2) capture subsystem
- An algae-based CO2 utilization subsystem
“While these individual components have been used before, they’ve never been combined in this way,” OBrien said. “Part of our aim with this project is to standardize and modularize these components, so this design can be replicated and more easily maintained. We hope this could become the global standard for innovative, low-emission coal-fired power.”
An ultra-supercritical system operates at intense pressure, which means steam is more efficiently converted to the mechanical energy that drives the turbines to produce electricity. Increased efficiency means less coal is needed for each megawatt of power produced, reducing emissions.
Including both natural gas combustion and energy storage will provide greater flexibility and resiliency. Varying demand is tough on coal-fired boilers, because frequent shut-downs and start-ups cause huge swings in temperature and pressure that cause stress on their components. Natural gas systems don’t suffer the same stresses; they can ramp up quickly to meet surging demand and can be shut down when demand drops. Likewise, the energy storage subsystem will enable the plant to store energy to meet fluctuating consumer needs for power.
An additional benefit is that the exhaust from the natural gas system can be used to pre-heat the coal system, reducing how much coal needs to be used.
The proposed design also includes technology, developed by Linde PLC BASF, to capture carbon emissions before they reach the environment. ISTC is overseeing a large pilot test of the performance, safety, and environmental compliance of this technology at Springfield’s City Water, Light, and Power (CWLP) plant.
Finally, the captured CO2 will be used to help grow algae that can be converted into biofuel, animal feed, or biochar soil supplement.
Subawardees for the project include:
- Doosan Heavy Industries, the developer of the HGCC technology and one of the world’s leading developers of boilers and turbines;
- Kiewit, one of the leading engineering, procurement, and construction firms for power generation-related construction, and;
- Global Algae Innovations, a company that specializes in the deployment of large-scale algae systems.
Other participants include Barr Engineering Co. (firing systems), Microbeam (fuel treatment), Envergex (control systems), and the University of North Dakota (additional coal sources).
This three-year front-end engineering design (FEED) study will provide DOE with a detailed understanding of the costs of scaling up this power plant design and could pave the way for the construction of this innovative plant in Springfield.
The City, Water, Light and Power plant in Springfield was chosen as the project site because it is already the test site for the carbon-capture system, its planned retirement of three older, less efficient boilers creates space for the hybrid coal-natural gas system, and a DOE CarbonSAFE project conducted by the Illinois State Geological Survey (ISGS) previously demonstrated that the region’s geology will support underground storage of CO2.
OBrien and co-principal investigator Mohamed Attalla, director of U of I Facilities & Services, and ISTC project manager Les Gioja lead the project, providing combined expertise in power generation technologies, clean-energy generation, and large-scale construction.
ISGS continues studying CO2 sequestration near Terre Haute, Indiana
ISGS is participating in a second DOE Coal FIRST project, which will study the potential redevelopment of the Wabash Valley Resources coal gasification site in West Terre Haute, Indiana. That team, led by Wabash Valley Resources, seeks to convert the existing plant so it can burn biomass as well as coal while producing hydrogen that can be used to generate electricity or sold as a product. This project will capture CO2 for storage in nearby deep saline reservoirs and aims to achieve net-negative carbon emissions by sequestering more carbon than it produces. This connects to an ongoing CarbonSAFE project that ISGS is carrying out at the Wabash Valley Resources site, studying the feasibility of developing commercial-scale CO2 storage at the location.
These projects are supported by the U.S. Department of Energy, Office of Fossil Energy, National Energy Technology Laboratory.