Product Briefing Outline: Saflex, a business unit of Solutia, has launched the Saflex Radiant White PA27 encapsulant, which was developed in collaboration with Oerlikon Solar to improve conversion efficiencies of its tandem-junction ‘micromorph’ thin-film module technology. Saflex PA27 is manufactured to an ultra-thin thickness of 0.51mm compared to standard PVB encapsulants and is the first ultra-thin reflective PVB encapsulant available for use in the solar market.
Problem: Traditionally, the role of encapsulants is to ensure long-term durability and performance of solar panels by protecting critical electrical components from rain, heat, and humidity; however, the material is expensive and passive in nature in relation to improving cell or module efficiencies. Currently, most solar modules utilize a reflective metallic stack or reflective white coat to redirect light back through the film for improved energy conversion, adding to the process steps and manufacturing costs.
Solution: Saflex PA27 is manufactured to an ultra-thin thickness of 0.51mm compared to standard encapsulants, which typically range from 0.76mm to 1.14mm in thickness, thus resulting in a material reduction of 33% to 55%, respectively. It incorporates the reflective benefits provided by more traditional reflective material layers into the encapsulant, giving module manufacturers a cost-effective solution to increase solar panel efficiency and simplify the manufacturing process. Saflex PA27 also has improved electrical insulation with a two-order-of-magnitude increase in bulk resistivity. This equates to significant improvements in the wet insulation resistance of the module, leading to a reduction in current losses to ground and an increase in the power collected from each module. Test results confirm Saflex 3G PVB to be less moisture sensitive, which enables high adhesion especially at the edges, even as environmental conditions, including humidity, fluctuate.
Applications: Thin-film modules.
Platform: Saflex PA27 is based on proven 3G PVB chemistry, which was first introduced in 1997. PA27 is RoHS approved, both IEC certification and UL testing pending.
Availability: April 2010 onwards.