The mission of the Supercritical Transformational Electric Power (STEP) program is to design, build, and operate a 10 MWe pilot scale facility using an indirect-fired sCO2 power cycle, demonstrate component performance and cycle operability over a range of operating conditions, and show progress towards a lower cost of electricity. The STEP facility will serve as an opportunity for industry and government to work together to develop and mature the technology at the pilot-scale to facilitate commercialization. The investment will spur the development of necessary designs, materials, components, operation and control systems, sensors, and understanding and characterization needed for commercial acceptance of large scale sCO2 power cycles. Where appropriate the facility will be used to address and resolve technology-specific issues relevant to the different heat source applications.

NETL Basis of Cost Estimate of STEP Facility
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Since the sCO2 power cycle has broad applicability to multiple heat sources, including fossil, nuclear, solar, and geothermal, the STEP facility will be supported by the DOE sCO2 Crosscut Initiative. This is a collaborative effort between the DOE Offices of Nuclear (NE), Fossil (FE), and Energy Efficiency and Renewable Energy (EERE) to reduce technical barriers and risks to commercialization, enabling programs with common technical challenges to work together toward solutions. The FE base program work in Supercritical Carbon Dioxide Technology is closely coordinated with and supportive of the STEP program. STEP projects will support the mission of this program.

Thar Energy Microtubular Heat Exchanger Layout
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