The word “biorefinery” was coined to describe an industrial process of cracking biomass resembling the industrial cracking of fossil carbon (Kamm and Kamm, 2005). But it can also be seen as an "Intermediary Object" (Vinck 2009) socially constructed by macroactors in European projects such as "Star-Colibri", with a view to developing a particular vision of the transition towards the use of renewable resources. Narrative approaches are mobilized by sociologists to describe the complexity of systemic change in a multilevel perspective (Grin, Rotmans and Schot, 2010). Narratives have also been used in Economics and Management of Technologies since the works of David (1985) to Dumez and Jeunemaitre (2005), to identify and describe various potential technological trajectories. We used a similar (analysis, cognitive process, method, procedure.) in the course of an interdisciplinary approach involving economists chemists and biochemists. Our "narrative approach" aims at highlighting the diversity of technological expectations. In the dominant vision of the biorefinery, large-scale units crack the biomass into a limited number (top 10 chemical intermediates) of standardized "small molecules", easily purified and introduced into the traditional petrochemical processes. Production of liquid fuels ("bio"-fuels) would enable economic operators to reach this large scale, while chemicals with high added value should ensure their economic balance (Bozell, Petersen 2010). However, other technical routes are worth considering: For example the intrinsic complexity and self-organization properties of biomass materials can be used as a way to introducing principles of green chemistry in processes operating more systematically on the macromolecular level ("one pot", whole plant, "reactive extrusion", modified starches, photochemistry and so on ..). They minimize fractionation steps and thus the use of energy or water. They can also entail smaller scale chemical units, which would not need to be stitched to the existing network of large-scale commodities production (of "bio"fuels,) and would be better rooted in local production areas. The discussion on the transition must therefore integrate the diversity of possible technical (ways) (routes) and examine how institutional policies support either of these solutions.