STEP DEMO PILOT PLANT (IMAGE) Southwest Research Institute Caption The Supercritical Transformational Electric Power (STEP) Demo pilot plant is the first facility of its kind to fire its natural gas heater and operate its turbine at an intermediate speed of 18,000 rpm. The $169 million, 10-megawatt supercritical carbon dioxide (sCO2) test facility at Southwest Research Institute (SwRI) in San Antonio is one of the largest demonstration facilities in the world for sCO2 technology. Credit Southwest Research Institute Usage Restrictions Images/Videos may be used by the public for educational and informational purposes only. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.