Streamlined Life Cycle Assessment ofTop-of-Rail Friction Modifier Application Systems: Focus on Trackside Technologies : Life Cycle Perspective on Trackside Friction Management inComparison to On-board Applications

Sammanfattning

Effective friction management between wheel and rail is essential for safe and sustainable railway operations. This study aims to assess the environmental impact of two Top-of-Rail (TOR) friction modifiers: a trackside system using TOR Armor and an on-board system using Keltrack® ER. The goal is to determine which system offers greater sustainability based on energy consumption and CO₂ emissions throughout their life cycles. The analysis was conducted using a streamlined Life Cycle Assessment (LCA) according to ISO 14040, covering the phases of material production, transport, use, and end-of-life. Data was collected from technical specifications, stakeholder interviews, and scientific literature. When specific data was unavailable, reasonable assumptions were applied to enable comparison. The results show that the trackside system consumes less energy (214,390 MJ) than the onboard system (245,700 MJ), a difference of 31,310 MJ, while the on-board system results in slightly lower CO₂ emissions (10,238 kg compared to 10,808 kg), a difference of 570 kg. The choice between systems depends on several factors, including cost responsibility, infrastructure ownership, and track layout. Trackside systems are typically managed by infrastructure managers, while on-board systems fall under the operator’s responsibility. Curved sections near residential areas may benefit more from effective lubrication than straight tracks in sparsely populated regions. If energy reduction is prioritized, the trackside system is more suitable, whereas the on-board system is preferable when reducing CO₂ emissions is the main goal. Since several assumptions were made in the analysis, especially regarding the production of lubricants, the results should be interpreted with some caution. Nevertheless, the study provides valuable insights for future decision-making on TOR systems. Further research is recommended to improve data availability, particularly concerning lubricant composition and manufacturing processes, in order to strengthen the reliability of environmental assessments.