Objectives and problems to be solved:
The fact that thin film solar modules appear optical more homogeneously and offer a greater scope for designing and integrating in facade elements make them better suited for facade applications than crystalline and polycrystalline silicon modules. With the development of the semi-transparent CIS facade module we intend to bridge the gap between the cost optimised power module design and architectural demands to gain greater acceptance from architectural point of view and to initiate in this way an increasing number of facade projects with integrated PV modules. The development of the CIS technology at Siemens Solar has led to maximum efficiency levels of close to 14 % on mini modules using manufacturing equipment and adequate process performance capable for large area pilot production. On the basis of this technology large area, frameless, semi-transparent CIS modules for facade applications will be developed. The activities within the project will result in the demonstration of a CIS facade module array with 12 % efficiency on active area at the completion of the project.
Description of the work:
Within the project the activities are assigned to three participants. Saint-Gobain Recherche will contribute to the project with the coating of the barrier layer; optional decorative layers and the Mo back electrode on float glass substrates. These activities involve the first steps of the module manufacturing sequence. Siemens Solar will carry out the next process steps such as series connection of the individual cells, precursor deposition followed by the absorber formation, window layer deposition and encapsulation. These process steps are not part of the project. The activities at Siemens Solar within the project are focused on the development of new processes for patterning the broad stripes vertically adjusted to the series connection lines to attain the semi-transparency of the module. Chemical etching, laser techniques and bead blasting have to be investigated and optimised. Additionally, methods for removal of the films along the circuit edges and for contacting the bus bars of the modules have to be developed particularly from an architectural and aesthetic point of view. The European Commission Environment Institute (Ispra) with its measurement equipment and experience in thin film solar module characterization will carry out module characterizations. That will involve the performance of the IEC 1646 test sequence, the investigation of transient effects of the electrical module parameters and the energy rating of the CIS modules under realistic test conditions. To avoid time consuming measurements of the electric parameters of the modules in the pilot production phase the flash measurement method will also be evaluated. Moreover, resulting from measurements of the system performance of a complete CIS module facade array contributions will be given to the facade module configuration and integration.
Expected Results and Exploitation Plans:
Prototype semi-transparent CIS facade modules and facade systems will be presented at the completion of the project. The exploitation strategy for the large area CIS facade modules is part of the marketing strategy of the two companies involved in the partnership. Within the project the companies necessary for the exploitation of the facade module are integrated, such as the supplier of the coated float glass substrates, PV facade module manufacturer and the facade module user.
Funding SchemeCSC - Cost-sharing contracts