Background: The transition towards a circular economy requires innovative approaches to resource efficiency, particularly in the energy–agriculture nexus (Song et al., 2024). Biogas is a key renewable energy carrier with strong potential for reducing greenhouse gas emissions while contributing to circular nutrient cycles (Alengebawy et al., 2022) However, current biogas systems in Northern Europe rely heavily on manure, which alone is insufficient to meet increasing renewable energy demands (Einarsson & Persson, 2017; Stolarski et al., 2020). The Accel AgroBiogas research project (2025-2027) addresses this gap by exploring how underutilised agricultural residues can be mobilised for sustainable biogas production. The project aims to accelerate biomass supply while ensuring environmental integrity, economic feasibility, and compatibility with food production systems.

Methods/Approach: Accel AgroBiogas adopts a cross-border, multi-actor approach involving partners from Sweden and Denmark, including universities, advisory organisations, public authorities, and industry stakeholders. Central to the methodology are four “Living Labs” established in different regions (3 in Sweden and 1 in Denmark), where farmers, biogas producers, researchers, and policymakers collaborate in real-world experimental settings (Huang et al., 2024). These Living Labs facilitate co-creation and testing of new biomass supply chains, focusing on agricultural residues such as straw, cover crops, beet tops, and surplus grassland. The project integrates field experiments, technical trials in biogas plants (including pre-treatment and digestion processes), and value-chain analysis to assess logistics, economic viability, and environmental impacts. In parallel, policy analysis and stakeholder dialogues are conducted to identify regulatory barriers and inform supportive policy frameworks.

Preliminary results:  Preliminary results indicate significant untapped potential in agricultural residual streams to increase biogas production without expanding land use or compromising food production. The project demonstrates that innovative cultivation strategies, such as cover cropping and sequential biomass systems, can enhance resource utilisation while supporting soil health and ecosystem services (Quintarielli et al., 2022). At the same time, technical challenges related to handling heterogeneous biomass streams, such as storage stability, pre-treatment efficiency, and impacts on digestate quality, are being systematically addressed. Early findings also highlight the importance of coordinated logistics and new business models to enable effective collaboration between farmers and biogas producers. Furthermore, policy inconsistencies between agricultural, energy, waste, and climate frameworks have been identified as critical barriers, underscoring the need for integrated governance approaches.

Discussion/Conclusions Accel AgroBiogas illustrates how circular economy principles can be operationalised through integrated, cross-sectoral collaboration. By valorising agricultural residues as energy resources, the project contributes to closing material loops, reducing emissions, and strengthening rural economies. The Living Lab approach ensures that innovations are context-specific, scalable, and socially embedded (Huang et al., 2024). Importantly, the project highlights that achieving a circular bioeconomy requires not only technological innovation but also institutional alignment and stakeholder engagement across value chains. The insights generated provide actionable pathways for policymakers, practitioners, and researchers aiming to scale sustainable biogas systems in Europe and beyond.