3M has launched 3M Solar Mirror Film 1100, a flexible reflective film for concentrating solar power (CSP), concentrating photovoltaics and solar thermal installations. This advancement is the result of extensive materials research, in-field studies and cooperative work with the National Renewable Energy Laboratory (NREL) dating back to the early 1990s.
The film combines a polymer front side with silver as the highly reflective layer. It is coated with a pressure-sensitive adhesive on the back side, complete with liner, and an opaque pre-mask on the front surface protects the film during assembly and eases installation, 3M explains.
The film features total hemispherical reflectance in excess of 94% and specular reflectance above 95% (at a 25 milliradian acceptance angle), according to the company. On-site testing with NREL has demonstrated the film's ability to maintain reflectance of more than 93% over 14 years.
3M Solar Mirror Film 1100 also enables greater design flexibility than glass alternatives, allowing for larger geometry reflectors than previously possible, 3M adds. Lightweight large aperture mirror assemblies have the potential to reduce the total installed cost of CSP systems by over 15%.