The Circular Bioeconomy (CBE) combines the concepts of bioeconomy and a circular economy. As an alternative concept to the current fossil-based, linear economy, it describes an economy based on the efficient valorization of biomass. It is regional in nature and aims to improve sustainability. An analysis of the transition process, by identifying its success criteria and assessing its impacts through the modeling of technology-specific scenarios, is necessary to ensure that CBE concepts are sustainable. However, a comprehensive consideration of regional influences on both is lacking. Based on extensive literature research and an expert survey, we develop a multi-criteria approach where we (i) present a comprehensive catalog of CBE success criteria and discuss their region-specific characters and (ii) develop a methodology based on evaluation matrices that enable CBE technologies to be matched with regions. The matrices support the evaluation of technological and regional characteristics influencing successful CBE implementation. The results show that the success criteria “biomass resources”, “technological”, and “social” are perceived as highly important, and that most of the success criteria are both region- and technology-specific, highlighting the relevance of developing matrices to match them. We describe such matrices indicatively for the two broadest and most important success criteria clusters “social acceptance” and “biomass supply chain”. With this, we substantiate the regional nature of CBE and raise the awareness on the importance of considering regional conditions in CBE transition processes. Furthermore, we provide practical guidance on how regional conditions can be reflected in the selection of technologies, e.g., in regional CBE technology scenarios.

Purpose: Insect cultivation on bio-residues exemplifies the circular bioeconomy (CBE) concept by integrating three core CBE strategies: the use of bio-residues, multi-output production chains, and cascading. The sustainability of CBE technologies using bio-residues needs to be evaluated on a case-by-case basis, taking into account regional aspects and the technologies’ future potential. This study provides methodological guidance for assessing the environmental consequences of diverting a by-product from its current to a future utilization pathway through a prospective and consequential life cycle assessment (LCA) at a regional level. Methods: We illustrate the developed methods with a case study of black soldier fly larvae (BSFL) rearing on an apple pomace (AP)–based feed in Hesse, Germany. We analyze the regional AP situation regarding availability, seasonality, spatial distribution, and market situation, through an industry survey among Hessian press houses and integrate this information into our LCA model to scale it to the regional level, consider regional transport scenarios, and reflect regional market effects of diverting AP. Furthermore, we systematically upscale the process chain to an early industrial scale. Results and discussion: The annual generation of 11,300 t_FM AP in Hesse could supply a small industrial BSFL plant. AP occurs with high spatial density in the south of Hesse. Press houses are concerned that the cost of AP disposal will increase and that it will be difficult to find a recipient for AP in the future. These aspects support a new and centralized use of AP. However, its high seasonality and unstable nature is a hurdle. Diverting the AP annually generated in Hesse from its current utilization as biogas substrate or ruminant feed to insect farming results in a reduction compared to the status quo in land use by 6.4E + 05 to 6.8E + 05 m²a crop eq and in freshwater eutrophication by 3.7E + 03 to 3.8 E + 03 kg P eq when BSFL replace soybean meal. However, most environmental impacts show an increase, for example, global warming potential increases by 3.6E + 07 to 3.8E + 07 kg CO₂ eq. The LCA results identify improvement options such as reducing the feed conversion rate and optimizing the use of feed additives. Conclusion: This study shows how the regional situation of an industrial by-product can be investigated through a regional industry survey and how this information can be integrated into a cLCA model using a methodological framework. We show that the market situation of by-products can differ regionally, emphasizing the need of region-specific integration into cLCA models.

The Circular Bioeconomy (CBE) combines the concepts of bioeconomy and circular economy. As an alternative concept to the current fossil-based, linear economy, it de-scribes an economy based on the efficient valorization of biomass. It is regional in nature and aims to improve sustainability. An analysis of the transition process, by identifying its success criteria and assessing its impacts through the modelling of technology-specific scenarios is necessary to ensure that CBE concepts are sustainable. However, a compre-hensive consideration of regional influences on both is lacking. Based on extensive literature research and an expert survey, we (i) present a compre-hensive catalog of CBE success criteria and discuss their region-specific character and (ii) develop a methodology based on evaluation matrices that enable to match CBE technolo-gies with regions. The matrices support the evaluation of technological and regional characteristics influencing the successful CBE implementation. The results show that the success criteria "biomass resources", "technological", and "social" are perceived as highly important, and that most of the success criteria are both region- and technology-specific, highlighting the relevance of developing matrices to match them. We describe such matrices indicatively for the two broadest and most im-portant success criteria clusters “social acceptance” and “biomass supply chain”. With this, we substantiate the regional nature of CBE and raise the awareness on the importance of considering regional conditions in CBE transition processes. Furthermore, we provide practical guidance on how regional conditions can be reflected in the selection of technologies, e.g. in regional CBE technology scenarios.