A Life Cycle Assessment of early-stage production processes in multi-Si solar panels: Metallurgical silicon to ingot casting

Abstract

Rapid population growth and technological advancement have intensified environmental challenges such as natural resource depletion and climate change, increasing the need for sustainable production strategies. Life Cycle Assessment (LCA) plays a crucial role in evaluating the environmental impacts of products and processes across their entire life cycle. While solar energy is widely regarded as a clean and renewable energy source, silicon-based solar panels involve notable environmental burdens during their production, transportation, and end-of-life stages. In particular, high-energy consumption, extensive chemical use, and waste generation significantly influence their overall environmental performance. This study aims to quantify the environmental impacts associated with the production of silicon-based solar panels. The assessment focuses on key manufacturing stages, including metallurgical silicon melting, multi-crystalline silicon purification, and ingot casting. The analysis was conducted in accordance with ISO 14040/44 standards using SimaPro software, the Ecoinvent database, and the CML impact assessment method. Environmental impact categories such as global warming potential, resource depletion, aquatic ecotoxicity, and terrestrial ecotoxicity were evaluated. The results indicate that energy-intensive and chemically demanding processes, particularly silicon purification and wafer-related stages, are the primary contributors to the overall environmental burden of solar panel production.