This deliverable presents a techno-economic assessment of perovskite/Si tandem solar cells for gigawatt-scale manufacturing scenarios relevant to a potential European PV industry. Based on a benchmark production capacity of ~10 GW, the study evaluates material availability, equipment readiness, and process assumptions to estimate Cost of Ownership (CoO) and Levelized Cost of Electricity (LCoE) for tandem technology compared to established silicon PV. The analysis indicates that competitive CoO levels and LCoE values comparable to current silicon-based technologies are potentially achievable, provided that key top-cell processing steps are industrialised and scalable supply chains are secured. Further technology maturation and process definition are required, and full economic competitiveness will also depend on broader market and policy conditions affecting PV manufacturing in Europe.