From Wafer to Module: Cost-Effective High-Efficiency Silicon Technologies

In the “WaMTec” project, companies and research institutes from four European countries are working on the further development of technologies for the manufacture of silicon wafers, solar cells and modules. Crystalline silicon solar cells dominate the global PV market thanks to decades of cost reductions and efficiency improvements. However, rising production volumes are exacerbating resource constraints – particularly regarding silver for cell metallisation. At the same time, efficiency levels must continue to rise and manufacturing costs must fall. WaMTec is addressing these challenges with innovations across the entire value chain.

Initial Situation

Solar cells based on crystalline silicon wafers continue to account for the largest share of the global PV market. This dominance has been achieved through significant reductions in manufacturing costs and substantial improvements in product efficiency over the past few decades. However, the availability of the materials used is also crucial to this success. Nevertheless, the use of materials such as silver for the metallisation of solar cells is becoming increasingly problematic due to scarce resources and rising solar cell production. Furthermore, the energy conversion efficiencies of solar cells and modules must be continuously improved, and further potential for cost reduction must be exploited.

Objective

In the “WaMTec” project, we focus on reducing costs (CAPEX and LCoE) and increasing the efficiency of c-Si solar modules by addressing a large part of the

value chain: starting with the fabrication of silicon wafers, through the manufacture of solar cells, their integration into solar modules and their testing in outdoor test installations. The work is structured into work packages.

The specific objectives are:

• To improve the quality (10 ms lifetime) and reduce the cost of p-type c-Si wafers
• To increase the efficiency of p-type TOPCoRE solar cells to 25.5% – by replacing screen-printed Ag contacts with electroplated Cu contacts, thereby reducing silver consumption by 90%
• Single-sided dry etching of Si layers using climate-friendly F2 gas
• Improving light management in solar modules
• Testing the outdoor performance of solar modules using technologies from the project
• Reducing cell production costs (including wafers) by approx. 10%, leading to a reduction in LCoE of approx. 4%.

Approach

In cooperation between the project partners ODTÜ-GÜNAM (Turkey), Nines PV (Ireland), NorSun (Norway), Schmid (Germany), Smart Solar (Turkey) and Fraunhofer ISE, progress is to be achieved along the value chain for the manufacture of solar modules. The aim is to significantly reduce costs and validate new solar module technologies in outdoor tests.

The “WaMTec” project is funded by the Federal Ministry of Economic Affairs and Energy (BMWE).