Securing Eu Clean Technology Supply Chains: Learning Rates in Material Recycling and Strategic Stockpiling

Abstract

This study examines how the European Union (EU) can achieve its 40% target for domestically sourced clean technologies by 2030, using solar photovoltaic (PV) modules as a case study. We determine the cost-optimal power generation capacities at the EU level through 2050, categorizing solar PV supply into four sources: imports, domestic manufacturing, remanufacturing (via upstream material recycling), and withdrawals from a strategic stockpile. A key feature of our approach is the explicit modeling of learning rates, linking remanufacturing investment costs to cumulative installed capacity. Results indicate that learning rates between 3.5% and 5.0% enable remanufacturing to supply 13.2% to 36.6 % of newly installed solar PV capacity. The strategic stockpile plays a crucial role in meeting the 40% benchmark, particularly in the late 2020s and early 2040s. Moreover, only under very high learning rate assumptions-approaching 25%, consistent with historical trends in solar module manufacturing outside the EU-does the reliance on stockpiling diminish entirely. We conclude that under anticipatable cost reductions in material recycling and remanufacturing, stockpiling remains a critical mechanism for complementing domestic remanufacturing, enhancing supply security, and advancing energy autonomy.