A Life-Cycle-Based Environmental Passport for High-Voltage Substations

The environmental passport was developed using a life‑cycle‑based approach aligned with ISO 14040 principles. The scope covers the production, transport, and construction phases, selected elements of the use phase, and end‑of‑life processes. Benefits beyond the system boundary are excluded due to uncertainties associated with future scenarios and limited relevance for early design decisions. Data collection followed an iterative process reflecting the realities of design‑phase information availability. Inputs were derived from Building Information Models and design documentation for material quantities and component identification, supplemented by supplier raw material passports where available. Generic environmental datasets (e.g., ecoinvent) and expert judgement were used to address data gaps. Environmental impacts were calculated at component level and aggregated into a structured environmental passport at substation level, using multiple impact categories and a single‑score indicator. Hotspot analyses were performed to identify dominant contributors by component type and life cycle stage. The case study informs conclusions on the scalability of the approach, the need for standardisation, and the practical conditions required for effective adoption of environmental passports in the high‑voltage sector.