U.S. Department of Energy

Scattering Solar Thermal Concentrators

Pennsylvania State University logo Graphic of an orange circle in the top right with blue lines below it.

Illustration of a scattering solar concentrator in which light collected by a cylindrical Fresnel lens is focused within a curved glass "guide" sheet, where it is redirected into confined modes by a small mobile scattering element and transported toward heat transfer elements at the edges.

Pennsylvania State University, under the 2012 SunShot Concentrating Solar Power (CSP) R&D FOA, is designing and testing a novel solar collector system that relies on stationary optics, avoiding the need for mirror movement. The system is capable of achieving optical performance equal to state-of-the-art parabolic trough systems, but at a lower cost.


The research team is working to demonstrate a scattering solar concentrator with optical performance equal to existing designs of state-of-the-art parabolic troughs, but with the added benefits of immunity to wind-load tracking error, more-efficient land use, and elimination of movable heat-transfer elements. The goals of this project are to:

  • Demonstrate a small-scale, fully functioning prototype and test its performance outdoors
  • Attain break-even optical performance compared against existing parabolic troughs
  • Improve the overall performance and reliability of the collector field.


The Penn State scattering concentrator represents an entirely new way of concentrating sunlight. It incorporates fixed-focus collection optics and scattering into the waveguide modes of a guide sheet. This innovative design represents a hybrid between the high efficiency of conventional geometric optical concentration and the stationary simplicity of luminescent light-trapping. The design's success constitutes a leap forward in performance and reliability for the collector field—thanks to immunity from wind loading and eliminating the need for movable heat-transfer elements and spectrally selective coatings.

Publications, Patents, and Awards

SunShot logo

The SunShot CSP R&D program seeks to accelerate progress toward the cost target of $0.06 per kilowatt-hour through novel and revolutionary research into CSP technologies. Learn about other DOE competitive awards for concentrating solar power research that are in progress.