U.S. Department of Energy

Low-Cost Self-Cleaning Reflector Coatings for CSP Collectors

Oak Ridge National Laboratory logo Series of black and white photos from a microscope showing water droplets falling on a flat, dust-covered surface.

Successive frames showing a stream of water drops picking up and removing dust and dirt particles from a highly superhydrophobic surface. Image from ORNL

The Oak Ridge National Laboratory (ORNL), under the National Laboratory R&D competitive funding opportunity, is developing self-cleaning, optically transparent coatings that can be applied to the surfaces of heliostats and collector mirrors in concentrating solar power (CSP) systems. The coatings can help to achieve the SunShot Initiative cost goals by reducing the time and costs associated with cleaning collector and heliostat mirror surfaces and increasing the reliability and efficiency of CSP systems.


The research team has developed optically transparent superhydrophobic (SH) materials and coatings based on nanostructured silica surfaces that can address the soiling and maintenance issues of CSP systems. In this project, the team is investigating and optimizing the adhesion, transmittance, and water and dirt repellent properties of these multifunctional nanostructured surface coatings. The team is working to improve the technology using a suspension of SH silica nanoparticles, polymeric binders, and solvents that can be applied to large area surfaces using simple low-cost spray coating techniques developed by the commercial paint industry.


This project derives innovative new coatings by modifying high surface-area nano-structured silica particles with self-assembled low surface energy monolayers. The coatings will be transparent over the entire ultraviolet-visible near-infrared range and will be applicable to surfaces other than glass, making them suitable for other retrofitting and refinishing applications.

Publications, Patents, and Awards

At this time, this project does not have published articles, patents, or awards.

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Learn about other DOE competitive awards for concentrating solar power research that are in progress.