Environmental Life Cycle Analysis (LCA) of a high temperature solid oxide cell (SOC).

Solid Oxide Fuel Cells (SOFCs) have emerged as a highly promising solution in the transition toward sustainable and decentralized energy systems. Operating at high temperatures, SOFCs enable efficient electrochemical energy conversion with minimal pollutant emissions. Beyond their operational efficiency, SOFCs offer unique advantages such as fuel flexibility, long service life, and low emissions of nitrogen oxides, particulates, and unburned hydrocarbons. Furthermore, their reversible operation mode enables them to function as Solid Oxide Electrolyzers (SOEs), allowing for efficient hydrogen production and energy storage. Despite these benefits, a comprehensive evaluation of their life cycle environmental impacts is essential to validate their role in sustainable energy systems. This thesis, conducted within the framework of the EU-funded AMPS project (Automated Mass Production of SOC Stacks), focuses on the environmental sustainability assessment of SOFC stack manufacturing processes. The primary objective is to perform a cradle-to-gate Life Cycle Assessment (LCA) of a 1 kW Elcogen SOFC stack comprising 40 cells, analyzing the environmental impacts associated with the production of individual cells, interconnects, and stack assembly. The study utilizes the Environmental Footprint (EF) v3.1 methodology across four key impact categories: climate change, acidification, particulate matter formation, and resource depletion. Results reveal that the sintering process is the most energy intensive stage, contributing significantly to greenhouse gas (GHG) emissions due to high energy demand. Other impactful components include the anode, cathode, and barrier layer, largely driven by the extraction and processing of nickel, cobalt, and rare earth elements. The interconnects also pose notable impacts owing to stainless steel production. To address these challenges, two mitigation scenarios were examined: (1) a 15% reduction in raw material consumption, and (2) a significant reduction in specific energy usage through process automation. The first scenario led to modest improvements up to 12.2% in material resource depletion and less than 10% in other categories, highlighting the limited impact of material savings alone. In contrast, energy optimization yielded substantial environmental benefits, reducing global warming potential by 66%, acidification by 32%, and particulate matter formation by 36.5%. These findings underscore that reducing energy intensity, particularly in the sintering phase, is the most effective strategy for enhancing the sustainability of SOFC manufacturing process.