Integrating Sustainability into Engineering Practice: Analyzing the Gap Between Theory and Application in Student Design Projects

Sustainability has long been part of engineering education and is becoming increasingly relevant due to global transformation. Future engineers will play a crucial role in developing sustainable solutions in technology and product development. However, theoretical understanding alone is insufficient: meaningful integration into concrete design processes requires practicable methods and operational tools. In this context, the course “Sustainable Product Development” at Leibniz University Hannover teaches theoretical foundations of sustainability methodology in product engineering with a focus on their application in product development, which students apply in practice-based design projects. In recent iterations, students were tasked to improve consumer products regarding sustainability – without methodological guidelines or specialised tools. Implementation therefore, followed an intuitive approach, guided by individual understanding and pragmatic design logic. This study analyses selected outcomes from these projects to examine how students address sustainability when no structured methods are provided and what discrepancies arise between theoretical understanding and practical application. The aim is to derive requirements for practice-oriented tools that support the transfer of sustainability knowledge into engineering practice. The analysis identifies aspects that were intuitively considered as well as systematic gaps. It assesses the extent to which theoretical principles were reflected in design outcomes and where concrete tools and support formats are lacking for effective implementation. Although students recognised and attempted to apply sustainability principles, they faced operational limitations, especially in translating abstract concepts into design decisions. The absence of actionable methods complicated the transition from theory to practice, highlighting the gap between instruction and application and the need for practical, methodologically grounded tools in product development. This work contributes to engineering sustainability research by demonstrating how students intuitively implement sustainability based on theory without practical guidance and identifying where targeted support is needed. The findings provide a foundation for further research and the development of practical and didactically aligned tools that promote the implementation of sustainable principles in product development.