Supercritical carbon dioxide |
A step forward for sCO2
power cycles (STEP) pilot plant, located at Southwest Research Institute’s headquarters, San Antonio, TX, USA. This Mechanical completion has been achieved at the Supercritical CO2
10 MWe pilot, called STEP Demo, is a complete operating power plant designed to validate sCO2 based power generation, which promises higher efficiency, reduced costs, and lower emissions. It is among the world’s largest test facilities for indirect-fired supercritical carbon dioxide technology
John Marion Senior Program Director, Carbon Management and Conversion, and Bill Follett Program Director, sCO2 , GTI Energy Transformational Electric Power
Above: The STEP Demo 10 MWe pilot facility
Compared to conventional steam-based power generation, the supercritical carbon dioxide Brayton power cycle uses CO2
under high
pressure and high temperature supercritical conditions, as a closed-loop working fluid. The cycle features more compact components, such as turbomachinery that’s 1/10th the size of conventional steam turbine systems. It uses less fuel and consumes less water, and advanced configurations can enable zero emission power generation. The sCO2
power cycle responds
quickly and efficiently to changes in demand, enabling electricity grids to integrate baseload generation with renewable solar and wind power. It is a versatile technology that can make use of diverse sources of heat, including turbine exhaust, concentrated solar, biomass, geothermal, nuclear, and industrial facilities. The US Department of Energy (DOE) through its Solar, Nuclear, and Fossil Energy offices, sees the potential of this technology across many applications. Enabled by advancements in materials, manufacturing, and numerical modeling, the US DOE launched a comprehensive programme of R&D projects more than ten years
ago to advance the component technologies and to demonstrate operation of integrated systems. This included a 1 MW power loop project led by SwRI, which achieved the highest turbine operating temperatures to date (715°C) and encouraged further validation at a larger commercially relevant scale. This culminated in the current 10 MWe STEP pilot project, aka STEP Demo. It will include the testing of two power cycle configurations: simple cycle with TiT (turbine inlet temperature) of 500°C; and RCBC (Recompression Brayton Cycle) with TiT of 715°C. The STEP pilot has also been designed to support development and testing of future sCO2 technologies, such as new components developed by OEMs or novel cycle configurations.
Public–private partnership is critical GTI Energy is honoured to lead this $159 million government/industry partnership, teaming with Southwest Research Institute, GE Research, and the US DOE National Energy Technology Laboratory. Revolutionary innovation often carries both technical and market risks. This project is possible because of support from both public
14 | November/December 2023|
www.modernpowersystems.com
and private organisations. The project is grateful to its Joint Industry Partners (JIP members) including American Electric Power, Southern Company Services, EGAT (Electric Generating Authority of Thailand), Engie, KEPCO (Korean Electric Power Company), Natural Resources Canada, CSIRO (Commonwealth Scientific and Industrial Research Organisation), and the State of Texas (TCEQ). We continue to actively seek new participants from the USA and internationally. GTI Energy is a non-profit research institute that develops, demonstrates, and commercialises new energy technologies that make a difference for consumers, for industry, and society. For more than 80 years, we’ve worked hard to meet the energy challenges, transforming scientific concepts into real world solutions. Achieving this takes teamwork, and this STEP Demo project is a great example.
Significant achievements Along the way to mechanical completion, we have seen a number of notable accomplishments. The compressor loop has been successfully demonstrated (at supercritical CO2
conditions), including the main compressor, the sCO2
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55
