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

SunShot Initiative

Next-Generation Low-Cost Reflector

PPG logo Illustration of a rectangle with four layers.

Schematic cross section of a first surface mirror.

PPG, under the Baseload CSP FOA, is producing a durable first-surface mirror with improved optical performance and geometry design to reduce the unit cost of the reflector subcomponent in a concentrating solar power (CSP) application.

Approach

PPG Industries is creating an ultra-large, front-surface glass mirror with an inorganic protective hardcoat. This approach is working toward reduced operation and maintenance costs and a lower overall unit cost of the reflector assembly. Moving to a larger-sized glass reflector also reduces manufacturing costs because fewer mirrors are needed. The project aims to achieve an estimated levelized cost of electricity (LCOE) of less than $0.08/kWh.

Innovation

The current LS3-sized mirrors use only 55%–65% of the available capacity of existing glass coating equipment. PPG is pioneering a design that:

  • Represents a size increase of 2.5 times more than current mirrors
  • Uses a first-surface mirror as opposed to a second-surface mirror
  • Adds a proposed alumina hardcoat to eliminate the passage of light through the glass material while also providing durability and anti-soiling properties
  • Achieves a reflectivity of 97%.
SunShot logo

Quarterly Progress Reports

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