In the TKI – NeFT project, Brightlands Materials Center together with Yparex develop high refractive index polymer films as encapsulants for silicon PV modules, to increase the solar cell efficiency.

Current commercially available silicon PV modules have cell efficiencies around 20%. The loss in efficiency results partly already from light reflection at the interface between glass cover – encapsulant and encapsulant – PV cell. To reduce the light reflection and therefore increase cell efficiency, we develop encapsulants with an optimized refractive index.

To increase the refractive index of the encapsulant, we develop high refractive index pigments and integrate those into the polymer film, which is used as encapsulant.

The pigment loading in the encapsulant can be tuned to adjust the refractive index to the desired value.

The pigment size and distribution in the polymer film is optimized to realize low haze and scattering values.

Using BMCs and Yparexs newly developed encapsulant in silicon PV cell a relative cell efficiency improvement can be achieved.