U.S. Department of Energy - Energy Efficiency and Renewable Energy

SunShot Initiative

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.