New PV Encapsulant Helps Deliver More Power at Lower Cost

In the drive for more cost-effective solar energy, Oerlikon Solar and DuPont have collaborated on a new thin white reflective solar PV encapsulant sheet, called DuPont PV5223. This latest addition to the DuPont PV5200 Series of PVB sheets enables easier manufacturing of next-generation thin film PV modules that not only capture sunlight coming in, but also reflect more sunlight back through the module’s active layer, thus capturing an extra zap from every available ray of light.

DuPont materials research, guided by Oerlikon thin film manufacturing know-how, produced the DuPont PV5223 white reflective encapsulant sheet for use in Oerlikon multi-stack laminating processes.

The DuPont PV5223 white reflective encapsulant is placed on the back (non-sun-facing) side of Oerlikon Solar’s specially developed thin film coatings. Traditionally, reflective paints were used between the cell and the encapsulant to reflect light back to the active layer. By making a white reflective encapsulant, DuPont helps Oerlikon Solar eliminate the need for reflective paint.

Designed for use with Oerlikon Solar’s Micromorph technology, DuPont’s new PV5223 white encapsulant increases light reflectivity by more than 50% versus paint, to an almost perfect 94% reflectivity. What’s more, the added reflectivity comes in a super-thin 0.45-mm sheet well suited for Oerlikon Solar’s low-topology module design. The sheet is more than 40% lighter in weight than traditional 0.76-mm PVB encapsulants.

Tests conducted by Oerlikon Solar and DuPont show excellent retention of the 0.45-mm encapsulant’s performance properties after 1000 hours of damp heat aging. The white PVB sheet delivers stronger adhesion than clear PVB sheet materials, which translates into tougher, longer-life modules.

“The PV5223 sheet enables more power from our modules, lower material use, a lighter environmental footprint, and easier lamination. It all adds up to a bright outlook for our module manufacturing customers,” said Dr. Ivan Sinicco, senior manager module development at Oerlikon Solar.

“In rapidly evolving industries such as solar power, equipment and materials leaders often innovate faster and more effectively by increasing collaboration,” added DuPont photovoltaic encapsulants business director Steve Cluff. “DuPont’s market-driven science is supporting the solar industry’s race for lower cost per watt. DuPont appreciates opportunities such as this to respond to a leader such as Oerlikon Solar.”