ReflecTech® mirror film is a highly-reflective, silvered film intended for decades of use in outdoor applications. Laboratory and field tested, ReflecTech has proven it is the premier reflective film for optimal use in solar concentrators and other reflectors that require outdoor durability.

Origins

ReflecTech mirror film was developed in the 1990s by scientists at the National Renewable Energy Laboratory (NREL) focused on cost reduction and increasing durability of parabolic trough collectors. SkyFuel was awarded the exclusive worldwide license to manufacture and market it by NREL. Collaborative continuous improvements to increase the long-term durability of ReflecTech mirror film resulted with the addition of an abrasion resisting coating.

In a parabolic trough collector, ReflecTech mirror film is used to reflect sunlight on a receiver and deliver the performance of traditional glass mirrors at a fraction of the cost and weight.

Features:
High Reflectance

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Outdoor Weatherable

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Ultra-Lightweight

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Abrasion Resistant

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Dirt/Dust Resistant

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Commercially Proven

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Low Cost

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Self-Adhesive

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Construction

ReflecTech mirror film is constructed of a pure silver coating for high specular (mirror-like) reflectance and multiple layers of protective polymer films to protect against ultraviolet (UV) radiation and moisture. In addition, ReflecTech mirror film is the only mirror film with an abrasion resistant hard coat, for extensive long-term durability.

Application

ReflecTech mirror film has a pressure sensitive adhesive for lamination to smooth surfaces, such as an aluminum sheet. The film is applied by first removing the peel-off release liner that covers the adhesive and using a pressure (roll) laminator. Aluminum edge tape must be used to seal all edges and seams of the laminated reflector.

Properties

ReflecTech mirror film has high reflectance in the wavelength range important for harnessing sunlight for thermal power production. Hemispherical reflectance is plotted on the left axis while the ASTM sunlight standard is plotted on the right axis, both as functions of wavelength. The specular reflectance 94%.

Specular Reflectance ¹ 94%
Nominal Thickness 0.004”
4 mils
0.10 mm
Maximum Operating Temperature 140 °F (60 °C)
  1. At 1.4° acceptance angle and 660 nm measured with a D&S 15R Specular Reflectometer

Field and Laboratory Tested

ReflectTech mirror film has been field tested at the solar energy generating station (SEGS) plants in California since 2002 with excellent results, and is used by third-party customers in various single curvature solar applications. In addition, ReflecTech mirror film has undergone more independent testing in the laboratory and in the field than any other solar reflector in the world.

Test Standard Result
UV | Temperature | Moisture Test:
2 X UV | 30 °C & 60 °C | 5 % & 60 % Relative Humidity: 12,000 hour		 ASTM G 155 Pass
Outdoor Test:
5 X sunlight & hourly water spray: 7,500 hours		 ASTM G 90 Pass
Water Resistance Test: 30 days of immersion ASTM D 870 Pass
Cyclic Condensation Test:
100 % relative humidity | 30 °C & 60 °C: 100 cycles		 ASTM D 4587 Pass
Taber Abrasion: 30 cycles before and after weathering ASTM D 4060 Pass
Adhesion of Coating: cross hatch tape peel test before and after weathering ASTM D3359 Pass
Bending Test @ 25 mm radius and above ASTM D 522 Pass
Hail Test: front and back, 1” diameter ASTM E 822 Pass
Falling Sand Abrasion: 2 liters of 120 grit sand ASTM D 968 Pass
Thermal Cycling for Coatings: 30 cycles ASTM D 6944, Method B Pass
Humidity Freeze Test:
-40 °C to 60 °C, ambient to 83 % relative humidity: 10 cycles		 IEC 62108, Section 10-8 Pass
Corrosion Test: Salt Spray (Fog), 500 hr ASTM B 117 Pass

The graph below shows that after receiving the equivalent cumulative UV dose of over 35-years of outdoor exposure, no degradation and no loss in reflectance were measured in samples of ReflecTech mirror film.

“ReflecTech polymer film is a viable alternative to glass mirrors, offers comparable performance and durability, and is not susceptible to breakage as are glass mirrors.”
- Sargent & Lundy, LLC

ReflecTech® mirror film was developed in partnership with the U.S. National Renewable Energy Laboratory (NREL). (U.S. Patent No. 6,989,924)