Technological Development and the State of the Art

A number of groups are working on upscaling nc-DSC technology for indoor and outdoor applications. Details of technological processing are not normally provided at this stage, but some general information reported in various papers is summarised in this section.

The INAP/Germany consortium has been working on the upscaling and improvement of nc-DSC technology since 1995 [10-12]. The goal of the work at ШАР is to reach the pilot production stage for modules > 100 cm2 for high power applications. Their focus is on automating most process steps and reducing fluctuations in module properties introduced by manual handling and variable material quality. After the introduction of the monolithic concept by Andreas Kay [8], ШАР demonstrated the feasibility of monolithic modules with 30 x 30 cm2 panel sizes [10]. Since there were a lot of uncertainties at that stage concerning the materials used in this design, they decided to focus on the basic Z-type interconnected glass/glass module technology, described in Sect. 7.3.1. In 1998, an energy conversion efficiency of 7.0% had already been reported for a module with an active area of 112 cm2 containing 12 single cells [10]. Several sealing materials and interconnects were investigated in terms of permeability, heat resistivity, electrical properties and compatibility with nc-DSC technology. Working prototypes of 50 x 50 cm2 Z-type interconnected modules were demonstrated [13]. Technological details of the processing and performance are not known.

Sustainable Technologies Australia (STA) Ltd. started in March 2000 with the construction of the first manufacturing pilot plant for nc-DSCs based on Z-type interconnected glass/glass module technology. They opened their production facilities in May 2001. The building blocks for STA DSC products are solar cells with a size of 10 cm x 18 cm. These are assembled into four-cell modules. Prototypes of these modules are shown on the STA website [14].

ECN (Netherlands), IVF (Sweden), Leclanche SA (Switzerland), EPFL (Switzerland), Uppsala University (Sweden), IPM (Italy), DSM Research (Netherlands) and Pricer AB (Sweden) collaborated in a two year European project (from 1997 to 1999) where the whole range of aspects related to the production and testing of nc-DSC for indoor applications was investigated

[15] . Starting from lab-scale experience, the partners worked on the following items: evaluation of manufacturing concepts, development and preparation of materials and components, large scale batch processing of modules, standard testing and material, characterisation, production line design including com­puter simulation and cost analysis. Since then, mechanisation of individual process steps has continued at ECN, resulting in the realisation of a complete baseline for nc-DSC in 2001. This baseline is now used to produce solar cells with dimensions up to 10 cm x 10 cm for outdoor applications.

An interesting approach to applying nc-DSC technology on flexible sub­strates has been announced by Lindstrom et al. [16]. A new method was introduced which completely avoids the high-temperature sintering step by mechanically pressing the colloidal films. Efficiencies up to 5.2% have been obtained at 0.1 sun using plastic substrates. This press technique, operating at room temperature, offers the possibility of working on flexible substrates, and this provides the basis for a continuous production technique.

Updated: August 24, 2015 — 2:21 pm