Life Cycle Impact Assessment and Weighting in Switching Station: Insights from a Case Study

As evaluation has expanded to entire systems, the necessity of selecting diverse environmental impact categories in accordance with assessment objectives has become increasingly evident.

Eco-design, aiming to minimize life cycle environmental impacts, requires informed decisions on design and operational strategies. These decisions demand integration of multiple indicators expressed in different units, typically achieved through Life Cycle Impact Assessment (LCIA), which comprise characterization, damage assessment, and weighting processes, ultimately yielding a single aggregated score. However, applications within T&D remain limited, and methodological challenges are yet to be systematically addressed.

This study aims to investigate approaches for building an integrated environmental impact assessment framework to support eco-design for T&D. The analysis targets 145 kV switching stations —Air-Insulated Switchgear (AIS) and Gas-Insulated Switchgear (GIS) with different in configuration and installation areas. Using the LIME3 (Lifecycle Impact Assessment Method based on Endpoint Modelling 3) methodology for integrated assessment, environmental impacts were quantified across the entire life cycle, including raw material extraction, manufacturing, operation (conversion losses and sulfur hexafluoride (SF₆) leakage), end-of-life

(EoL), and land development. The assessment encompassed GHG emissions and four areas of protection. The assessment also considered electricity emission factors and the impacts of land use for seven countries.

As results indicate, AIS exhibited greater power losses during operation, whereas GIS emissions were primarily due to SF₆ leakage; overall, GIS showed a tendency toward lower GHG emissions compared with AIS. Conversely, integrated scores revealed that land use exerted a substantial influence. When land use was excluded, the relative contribution of materials and EoL stages increased, while the shares of operation and SF₆ decreased.

Furthermore, both GHG emissions and integrated scores varied significantly across countries, reflecting differences in electricity emission factors and land use. Integrated assessment also highlighted the impacts on social assets constituted a considerable proportion of the total. These results indicate that evaluation trends by areas of protection may differ from those based on

GHG, highlighting the importance of an integration of diverse environmental impacts that cannot be captured by GHG evaluation alone.

Based on the results, challenges in current methodologies were identified. First, it is necessary to ensure robust data compilation for materials unique to T&D and to improve the accuracy of evaluation methods covering from characterization to damage assessment. Second, since weighting methods are prone to subjectivity and socio-biases, it is crucial to correctly understand the limitations of each process and share them among stakeholders to achieve coherence with the intended goals.

Integration remains in its early stages. To develop rational and effective indicators that contribute to achieving eco-design in the T&D sector, cross-industry collaboration among stakeholders—including operators and manufacturers—is required to enhance data availability, establish assessment methods suited for T&D, and improve understanding and transparency of evaluation processes.