Eco-efficiency assessment of manufacturing carbon fiber reinforced polymers (CFRP) in aerospace industry

Abstract

Carbon fiber reinforced polymers (CFRP) are frequently used in aerospace industry. However, the manufacturing carbon footprint and direct cost are obstacles in the way of adopting CFRP in further aerospace structures. Therefore, the development of a combined ecological and economic assessment model for CFRP manufacturing is demonstrated in this paper. This model illuminates the proper developments for the decision-makers. In this work, the eco-efficiency assessment model (EEAM) is developed based on life cycle assessment (LCA) and life cycle cost analysis (LCCA). EEAM is an activity-based bottom-up decision support tool for the manufacturing process of fiber reinforced polymer (FRP). This paper discuses a case study of manufacturing CFRP wing ribs for a modern commercial aircraft as a part of the project LOCOMACHS. Ecological results of EEAM conclude that the carbon footprint of manufacturing wing rib made of CFRP thermoset by the technique of in-autoclave single-line-injection (SLI) is around 109 kg CO2-equivalent for each kg of CFRP. Moreover, fiber material is the main contributor in this carbon footprint. On the other hand, the economic assessment shows that the studied rib has a direct manufacturing cost of about 584 €/kg. In these results, labor work dominates the direct cost with 49%, while fiber and matrix compensate about 35%. As an activity-based assessment model, EEAM guides the decision-makers toward sustainable direct applications. It is concluded that direct applications for fiber waste reduction are beneficial for both eco-efficiency aspects. Energy consumption reduction is ecologically beneficial, while labor work reduction on the other hand is cost relevant. In aerospace industry, there is a clear potential for eco-efficient direct applications that satisfy both aspects.