The rapid development of blockchain technology, particularly tokenization, offers new opportunities for financing and advancing renewable energy systems. This paper explores how tokenization can serve as a financial instrument to facilitate the transition to green energy systems in Germany. Through a comprehensive bibliometric analysis, we identify a clear trend towards increased research on tokenization, with emerging use cases demonstrating varying degrees of applicability. However, in the energy sector, particularly as a financial instrument, a significant research gap remains. A finding was that regulatory frameworks and use cases significantly constrain its potential. Furthermore, academic literature has yet to develop guidelines and procedures for establishing tokenization as a financial instrument and to improve knowledge transfer to implementers. We conducted expert interviews with key stakeholders from the banking, sustainable development, digital infrastructure, and energy production sectors to gather qualitative insights on the potential impacts and challenges of tokenization. This paper contributes to research on tokenization by presenting the current state of tokenization research and highlighting the potential as a financial instrument for green energy systems for future research.