GTI Energy and Partners Achieve Supercritical Carbon Dioxide Conditions in San Antonio Pilot Project

March 7, 2023
Des Plaines, IL


Today, GTI Energy and its partners, Southwest Research Institute (SwRI) and GE Research, announced that the Supercritical Transformational Electric Power (STEP) Demo project, sponsored by the U.S. Department of Energy (DOE), successfully achieved supercritical carbon dioxide (sCO2) fluid conditions at its 10-megawatt electric sCO2 pilot plant facility in San Antonio, Texas. Supercritical CO2 power technology enables next-generation indirectly heated (like concentrated solar and nuclear energy) as well as directly fired natural gas electric power plants to be more efficient and help meet the global demand for a low-cost, environmentally friendly, flexible, and resilient energy transition.

“We are pleased to lead this critically important STEP Demo project to advance sCO2 toward commercial applications, and this milestone represents significant progress toward readying the facility for system-level testing,” says Don Stevenson, Vice President of Energy Supply and Conversion at GTI Energy. “We are grateful for the funding support and collaboration with the U.S. DOE’s National Energy Technology Laboratory and many industry partners from across the world to bring this project to fruition.”

Supercritical CO2 technology is applicable to a broad variety of low- and zero-emission heat sources, including waste heat from industrial sources, geothermal, biomass, concentrated solar, and natural gas with and without carbon capture. The cycle lends itself to highly compact turbomachinery, resulting in lower capital costs and reduced power plant size and footprint. It improves grid stability and resiliency with quicker response to changes in power demand that can occur with increased production of power from wind and solar. Water consumption for cooling can also be significantly reduced or even eliminated with the cycle, which can improve grid reliability during extreme weather events.

“The sCO2 power cycle is a breakthrough clean, compact, and high-efficiency power generation technology that can deliver significant environmental performance. We look forward to continued operation of the current test to demonstrate control and operability of this power cycle while validating system performance over long periods of time,” notes Bhima Sastri, Director of Energy Asset Transformation, DOE Office of Fossil Energy and Carbon Management.

The $155M STEP Demo project is funded by an industry consortium and a $124.5 million Cooperative Agreement from DOE’s National Energy Technology Laboratory. The STEP Demo pilot plant, built at SwRI’s campus in San Antonio, is among the largest demonstration facilities for sCO2 technology in the world. The pilot plant will demonstrate the efficiency and performance potential of the indirect fired, sCO2 Brayton power cycle. The facility is configured to enable optimization of system performance and characterization of critical components and subsystems. With a flexible design, the facility can be reconfigured as a testbed for future sCO2-cycle-based power systems and component development.

Organizations with an interest in gaining a better understanding of how sCO2 technology can improve high-efficiency power generation are welcome to join the STEP Demo pilot project.

About STEP Demo
The STEP Demo pilot facility will demonstrate a fully integrated electricity generating power plant using transformational sCO2-based power cycle technology that can offer dramatically improved size, performance, economics, and operational flexibility, with less environmental impact. OEMs, engineering companies, and power plant owner/operators from around the globe are invited to join this open project to gain a better understanding of how sCO2 technology can improve high-efficiency power generation.

About GTI Energy
GTI Energy is a leading research and training organization. Our trusted team works to scale impactful solutions that shape energy transitions by leveraging gases, liquids, infrastructure, and efficiency. We embrace systems thinking, open learning, and collaboration to develop, scale, and deploy the technologies needed for low-carbon, low-cost energy systems. GTI Energy leads the STEP Demo project as the prime contractor with the U.S. Department of Energy/National Energy Technology Laboratory.

About the Office of Fossil Energy and Carbon Management
The Office of Fossil Energy and Carbon Management (FECM) conducts research, development, demonstration, and deployment that focuses on technologies to reduce carbon emissions and other environmental impacts from fossil fuel production and use and from key industrial processes, particularly the hardest-to-decarbonize applications in the electricity and industrial sectors. Priority areas of technology work include carbon capture, carbon conversion, carbon dioxide removal, carbon dioxide transport and storage, hydrogen production with carbon management, methane emissions reduction, and critical minerals production. To learn more, visit the FECM website or sign up for FECM news announcements.

About National Energy Technology Laboratory (NETL)
NETL is the U.S. Department of Energy’s only Government-Owned, Government-Operated Laboratory. NETL focuses on the discovery, development, and deployment of technology solutions to enhance the nation’s energy foundation and protect the environment for future generations. These advanced technologies enable fossil fuels to produce the clean, reliable, and affordable energy needed to support increased domestic manufacturing, improve infrastructure, enhance global competitiveness, revitalize the workforce, and free the U.S. from dependence on foreign oil.

About Southwest Research Institute
Southwest Research Institute is a premier independent, nonprofit research and development organization using multidisciplinary services to provide solutions to some of the world’s most challenging scientific and engineering problems. Headquartered in San Antonio, Texas, SwRI occupies more than 1,500 acres, providing over 2.3 million square feet of laboratories, test facilities, workshops, and offices for approximately 3,000 employees who perform contract work for government and industry clients.

About GE Research
GE Research is GE’s innovation powerhouse where research meets reality. It is a world-class team of 1,000+ scientific, engineering and marketing minds (600+ Ph.Ds), working at the intersection of physics and markets, physical and digital technologies, and across a broad set of industries to deliver world-changing innovations and capabilities for their customers.

Become a project partner

This open project is welcoming new partners from around the world. OEMs, engineering companies, and power plant owner/operators are invited to join to gain a better understanding of how sCO2 technology can improve high-efficiency power generation.


For more information, contact Markus Lesemann directly.