TRANSMISSIVITY AND AESTHETICS OF OPTICALLY UNCOUPLED GLASSES FOR THE APPLICATION IN A PVT ROOF TILE

摘要

The purpose of this work was to investigate on different types of solar glass sheets that could be used as front side encapsulant in the PVT (Photovoltaic and Thermal) solar tile that is currently developed by the company Paxos Consulting & Engineering GmbH & Co. KG. Between the glass sheet and the solar cells a gap of several millimeters is foreseen and the space that is created is filled with inert gas to avoid heat loss. Two elements must be considered for the choice of the glass sheet. First the transmission needs to be as high as possible. On the other hand, the aesthetics of the tiles surface is of high importance for the product. For the aesthetics the homogeneity, the color and the potential glazing are of high interest. For the evaluation of the transmissivity of the 9 different glass types a measurement setup was constructed using a Xenon lamp and a large area detector which was constructed for that purpose to avoid the loss of photons that are strongly scattered. For the aesthetics, pictures were taken from the perpendicular view and from 45° with a light source being placed on the opposite side with an angle of incidence of 45°. The coated glasses and the glasses with texture on the backside have a low transmissivity compared to the other samples. The best aesthetics was achieved with coating #1 on Albarino P while the second best was achieved with uncoated Albarino P. The overall best choice for the encapsulation would hence be Albarino P as it gives a good transmissivity and an acceptable aesthetic.