Funding Opportunity: CSP: APOLLO
SunShot Subprogram: CSP
Location: Madison, WI
Amount Awarded: $1,899,986
Awardee Cost Share: $476,045


This project will address the fundamental challenges associated with the supercritical carbon dioxide (sCO2) cycle, including the need for a high degree of internal heat transfer that requires a substantial heat transfer area. Researchers at UW-Madison, in collaboration with FlowServe, will design, create, and test a fixed bed regenerator system that is compatible with the operating conditions expected in a sCO2 cycle. This project was announced on September 16, 2015 at the Solar Power International conference. Read the press release.


The research team will conduct a detailed economic study of an advanced power cycle, which will take advantage of the unique properties of sCO2 fluid. It will be compared to the conventional steam cycle. This includes analyzing a unique cycle layout that uses a regenerator instead of a recuperator, a type of heat exchanger, in the advanced carbon dioxide power cycle. The team will also design and construct scaled regenerators and high-temperature rotary valve components that will be tested at both the University of Wisconsin and Sandia’s prototype facility.


The use of fixed, switched-bed regenerators provides a simple, low-cost alternative for the recuperator. Regenerators have several advantages over recuperators. Because regenerators have lower construction and lower operation and maintenance costs, the potential for less fowling, and the potential to operate at higher temperatures, they can better convert the sun’s thermal energy to household electrical energy.