SwRI, Industry Collaborators Receive $8.5 Million from U.S. DoE to Develop High-Efficiency Hot Gas Turbo-Expander for Solar Plants

Southwest Research Institute and industry collaborators General Electric, Bechtel Marine Propulsion Corporation and Thar Energy LLC have       been awarded an $8.5 million contract by the U.S. Department of Energy  to develop a high-efficiency supercritical CO₂ hot gas turbo-expander for concentrating solar power plants. The award was given  through DOE’s SunShot Initiative, a collaborative national effort to make solar energy cost competitive with other forms of energy.

Because of the highly cyclical nature of concentrating solar power (CSP) plant operation, a supercritical CO₂ (sCO₂) hot gas turbo-expander must be able to operate at high temperatures and pressures over a wide range of load conditions while maintaining a high efficiency, handle rapid transient heat input swings and have very fast start-up capabilities to optimize the plant’s online availability.

“Over a three-year period, SwRI and its industry collaborators will design and develop a highly efficient, single or multi-stage sCO₂  hot gas turbo-expander that will advance the state-of-the-art from laboratory size (technology readiness level 3) to a full TRL6 mega-watt  scale prototype,” said Dr. Klaus Brun, a program director in SwRI’s Mechanical Engineering Division who will serve as project manager for  the effort.

A second objective of the project is to optimize novel, printed circuit heat exchangers for sCO₂ applications to drastically reduce their manufacturing costs. The scalable sCO₂ expander design and improved heat exchanger will address and close two critical technology gaps required for an optimized CSP sCO₂ power       plant and provide a major pathway to achieving CSP power at $0.06 per kilowatt hour, increasing energy conversion efficiency to greater than 50 percent, and reducing total power block cost to below $1,200 per  kilowatt installed.

The project, which will be conducted in three phases, is expected to  begin August 2012, and will continue through 2015. In phase 1,       researchers will design the expander and heat exchanger. Phase 2 will involve component fabrication and phase 3 will include performance       testing.

SwRI is an independent, nonprofit, applied research and development  organization based in San Antonio, Texas, with more than 3,000 employees       and an annual research volume of more than $581 million. Southwest Research Institute and SwRI are registered marks in the U.S. Patent and       Trademark Office. For more information about Southwest Research  Institute, please visit newsroom.swri.org       or www.swri.org