Anna J. Carr

Tessera: Scalable, shade robust module

This paper describes the development and output measurements on a new shade robust module, named the Tessera module. This module uses a novel electrical configuration, comprised of shade independent blocks protected by in-laminate diodes, with a mixture of series and parallel connections. By using ECNs existing back contact technology [1], no significant additional manufacturing costs occur. The design, method and manufacturing technology will be explained. The module leads to an increased annual output in case of shading and an increase in system safety due to lower heat dissipation: of 40°C instead of 130°C compared to standard diodes, and reduced failure of components. Annual yield has been calculated showing significant gains.

High voltage MWT module with improved shadow performance

In this paper we present a module concept designed for better performance under shadow conditions, incorporating also lower BOS costs. This concept is a high-voltage, low-current, shadow resistant, back-contact module concept. The experimental results under partial shading conditions for mini-modules having a Voc of 39.8V show a substantial improvement in shadow performance. The concept is based on the existing ECN MWT (Metal Wrap Through) back-contact technology [1], where the standard MWT cells are replaced by series connected “mini” cells. With the flexibility of the back-foil system we are able to approach a more linear shadow response for our module.

Relating indoor and outdoor performance of bifacial modules

Although flash tests under standard test conditions yields lower power due to transmittance of the back sheet, bifacial modules are expected to outperform their monofacial equivalents in terms of yearly energy output in the field. Different transparent rear side materials have been compared. We compare flash tests for these bifacial modules at various incidence angles with and without a light scattering panel behind the modules. The results of an outdoor study comparing modules with transparent back sheet and modules with state-of-the-art AR coating on the front glass will be presented.

Tessera: Maximizing PV Yield Performance with Size Flexibility for BIPV

Application of PV in the built environment, both as BAPV and BIPV, requires improved aesthetics, decreased operating temperatures of the modules and diodes, improved output under partial shading and reduced production costs while allowing the size and shape of the PV elements to be more flexible. ECN presents TESSERA: a novel PV module lay-out which allows linear shade performance, while at the same time allowing size and manufacturing flexibility which also leads to improved aesthetics as entire roof and façade areas can be utilized. Temperature measurements on module diodes shows the diodes in these PV modules only reach a temperature of 40C compared to 140C for conventional ones. Mechanical load tests to rails glued to the rear of the PV modules shows the interconnections are stable, allowing vertical, frameless installation. Hence, these TESSERA elements allow broader application of PV in the built environment.