D4.2 - Validated strategies for ensuring sustainable circularity plans

The BeBOP project is developing a novel Bio/e-Methanol production process combining biomass gasification with Solid Oxide Cell (SOC) technology, and demonstrates it within a TRL6 pilot plant. The core goal is to provide a substitute process based on renewables (both biomass and energy) for a fossil-based one (mostly natural gas). Therefore, ensuring that circularity principles are integrated from the earliest design stages is essential. This deliverable (D4.2 -Validated strategies for ensuring sustainable circularity plans) is the second report documenting the results of the Work Package (WP4), fully dedicated to Circularity in this project. It presents the main outputs of the circularity assessment conducted across six targeted Circularity Workshops and one Joint Workshop with strong stakeholders’ engagement, completed between January and December 2025.Building on the methodological framework presented in the previous report (D4.1) Tailored methods and impactful tools for boosting BeBOP circularity opportunities, the assessment applies four circular economy (CE) principles to the BeBOP life cycle: i) Narrowing (using fewer resources), ii) Slowing (extending component lifetimes), iii) Closing (creating material and energy loops), and iv) Regenerating (using renewable and non-toxic inputs). The BeBOP technical experts (Consortium partners), Advisory Board and broader Stakeholders’ Network members contributed to the assessment. A central output of the assessment is the BeBOP Circularity Indicator Set: 25 quantitative indicators across four life cycle stages – including feedstock selection and pre-treatment, gasification and gas cleaning, SOEC/SOFC operation and methanol synthesis - were proposed and further discussed for their suitability. More concretely, each indicator was selected based on its relevance to scale-up decisions and the feasibility of data gathering or direct measurements. Key Circularity indicators include the SOEC Stack Degradation Rate, the Cold Gas Efficiency of the gasifier, the Heat Reuse Efficiency, the Secondary Source Index and the Marginal Land Source Index. The indicators are process-specific by design, reflecting the unique characteristics of the BeBOP technology rather than generic circularity metrics. A systematic interdependency analysis revealed that some of the circularity indicators have inherent trade-offs. The most critical trade-off is between feedstock flexibility and both process performance and SOEC longevity. A second significant trade-off exists between maximizing renewable electricity use and system stability, as intermittent supply causes thermal cycling that shortens SOEC stack lifetime. On the other hand, heat integration is a predominantly synergistic area: improvements in heat reuse benefit multiple circularity objectives simultaneously and carry few negative trade-offs. These findings confirm that BeBOP circularity optimization is a multi-objective problem requiring system-level solutions. Based on the full assessment, four key recommendations are made for a long-term 100 MW commercial BeBOP scale-up: design for SOC longevity, build heat integration into the plant concept from the start, choose plant location strategically to maximize industrial symbiosis, and prioritize feedstock quality (in terms of a preferably low ash and impurity content) as a system-wide circularity lever. The indicators, trade-off matrix and circular business model scenarios developed in this WP will feed directly into the Life Cycle Assessment and the techno-economic analysis, and into the exploitation activities, especially the business cases for BeBOP.