High-Flux Solar Furnace

NREL's High-Flux Solar Furnace (HFSF) is a unique 10-kilowatt optical furnace that harnesses concentrated sunlight to test high-temperature processes or applications requiring high heating rates or solar concentration.

Photo of the high-flux solar furnace concave mirrors and heliostat in front of a blue sky.

At the top of NREL's South Table Mountain campus, the HFSF is a unique user facility for testing high-temperature processes and applications. The HFSF contains a tracking heliostat and 25 hexagonal concave mirrors that concentrate solar radiation to deliver 10 kilowatts of thermal power to a focal area about 4 inches (~10 cm) in diameter within the laboratory control room.

The HFSF can produce peak solar fluxes of up to 250 W/cm2 or 2,500 suns—which is equivalent to 10 kW of solar power—or higher if using secondary concentrators.

The solar furnace can quickly concentrate solar radiation to 10 kilowatts over a 10-cm diameter (2,500 "suns"), achieving temperatures of 1,800°C—and up to peak solar fluxes of 20,000 suns with specialized secondary optics to produce temperatures of up to 3,000°C. Secondary concentrators can modify the focal point and tailor flux levels and distributions to suit the needs of each research activity.

The HFSF facility is equipped with instrumentation to monitor solar radiation levels, automated controls to adjust the power of concentrated sunlight, data acquisition tools, and video monitoring of outside equipment. Because the HFSF concentrates actual sunlight, it offers an energy-efficient alternative to solar simulators, with tests performed under realistic rather than simulated conditions.

Availability for a Range of Research

The HFSF is available for testing by universities, businesses, the Department of Energy, Department of Defense, national laboratories, and other partners. It is suited for small-scale feasibility studies and testing of a wide range of technologies with a diverse set of experimental requirements. Research capabilities include:

  • Design-point or accelerated high-flux conditions for solar thermochemical hydrogen production research
  • On-sun functional component performance and materials testing of high-temperature materials, perovskites, solar-selective coatings, and components used in concentrating solar power systems such as receivers, collectors, and reflector materials
  • Evaluation and development of state-of-the-art measurement systems for extreme solar environments
  • Testing of prototype advanced converters and chemical reactors for solar-electric and solar-chemistry applications
  • Space applications including heat shields and lunar mining.

NREL's SolTrace modeling tool can determine secondary concentrator requirements and configuration. The facility also includes an ultra-accelerated weathering system for testing outdoor materials, which can provide up to 100× ultraviolet concentration to accelerate aging of materials used outdoors.

See more detailed specifications on the solar furnace. To discuss potential new applications or arrange a technical service agreement to use the facility, contact Judy Netter.