-- This project is inactive --

PPG, under the CSP R&D FOA, is aiming to develop and commercialize large-area second-surface glass mirrors that are superior in value, cost, and performance, to existing mirrors on the market today.


This project aims to develop a design and fabrication process for a mirror having:

  • A high solar weighted specular reflectance
  • Minimal optical performance degradation over the service lifetime
  • A cost to the concentrating solar power (CSP) systems builder less than that of the current market price.

The glass and coating developed under this award has gone through a few production runs for commercial purposes. In terms of lowering cost or improving performance, this award may have only minor impact; however, it may prove beneficial from a domestic manufacturing perspective.

Pictured are high performance mirror samples under test at the outdoor exposure facility at PPG Industries, Inc.


This project has the added environmental benefits of a lead-free encapsulant and no wet-silver process wastes. Production of a mirror with the proposed specifications requires that this project deliver:

  • A high transmission glass for the superstrate
  • Optical functional layers that deliver the performance required, an inorganic coating that protects the functional layers from chemical attack
  • An organic coating that protects the functional layers from mechanical attack
  • A cost-effective fabrication process.

Learn about other concentrating solar power research.