Modular and regenerative life cycle assessment indicators for sustainable power systems

International sustainability policies and energy-transition strategies are reshaping expectations for power system equipment design and assessment. Beyond conventional engineering performance, requirements increasingly emphasize eco-design, modularity, climate resilience, biodiversity, ecosystem services, human health, and stakeholder engagement. In this context, Life Cycle Assessment (LCA) is a key tool for evaluating power transformers. However, most transformer LCAs remain limited in scope, focusing on economic or environmental indicators within gate-to-gate or cradle-to-grave boundaries, and rarely supporting design decisions that enable circularity or regenerative outcomes across the full life cycle. This study addresses this gap by proposing an extended LCA framework that integrates modular and regenerative design principles. It aims to support sustainability assessment and design improvement at the individual transformer level, enabling identification of components, materials, and design choices that most influence life cycle performance. The framework also supports improvements at supply-chain and system levels, recognizing the need for coordination among suppliers, manufacturers, grid operators, and regulators, and seeks to move beyond impact minimization toward corrective design measures that enhance long-term environmental and social performance.