Window of sustainable bioprocess operation: towards merging environmental sustainability assessment and process operation at early-stage bioprocess development

Developing and optimizing sustainable bioprocesses require integrating technical feasibility and environmental sustainability assessment at an early stage of process development. Therefore, environmental impact estimations need to be performed alongside the development of novel bioprocesses, and ‘feasibility’ windows need to be defined, in which a bioprocess can be operated robustly and economically while being as environmentally friendly as possible. In this opinion, we summarize the progress made in the field of environmental sustainability assessment and its integration into bioprocesses at an early stage. We propose the ‘window of sustainable bioprocess operation’ (SBO window) as a concept to find operating conditions that match economic and environmental constraints. The insights obtained by the SBO window enable the back-translation of environmental constraints into bioprocess design optimizations and thus lay the foundation for a successful implementation of sustainable bioprocesses in the future.