Techno-economic analysis of biogas production: a literature review and bibliometric analysis

The accelerating global energy transition and the development of the circular economy have established biogas as a key renewable energy source that can reduce greenhouse gas emissions, improve waste management, and contribute to the Sustainable Development Goals. From this perspective, the techno-economic performance and sustainability of biogas systems have attracted growing attention in both academic and policy domains. This review aims to provide a comprehensive assessment of global research on biogas production and its techno-economic analysis, focusing on scientific dynamics, technological advances, analytical methods, and methodological challenges. An integrative review approach was applied, combining a systematic literature review with bibliometric analysis. A total of 287 Scopus-indexed publications were analyzed using VOSviewer to identify key research trends, collaborations, and thematic clusters. The qualitative synthesis explores advancements in anaerobic digestion technologies, biogas upgrading, and techno-economic analysis frameworks, with an emphasis on key performance indicators, cost metrics, modeling approaches, and uncertainty analysis. The results indicate a substantial increase in publication activity, from 3 publications in 2015 to 64 in 2024, accompanied by expanding international research collaboration. The analysis also reveals a methodological evolution from conventional cost-based evaluations toward integrated frameworks that combine technical, economic, environmental, and uncertainty assessment components. Recent studies reflect progress in co-digestion optimization, microbiological enhancement, life cycle-based assessments, and AI-driven modeling. However, significant gaps remain, including limited data reliability, regional inconsistencies, and the absence of harmonized methodologies for techno-economic analysis. The review highlights the need for standardized, transparent, and policy-oriented frameworks to strengthen the role of biogas in sustainable energy transitions. Future efforts should concentrate on improving the robustness of data, integrating environmental and socio-economic dimensions, and aligning techno-economic analysis practices with national and international energy strategies. Bibliometric analysis identified 5 major thematic research clusters covering anaerobic digestion, feedstock and waste management, environmental assessment, process engineering, and resource recovery. The review further demonstrates that recent advances in co-digestion, pretreatment technologies, microbiological enhancement, and biogas upgrading have contributed to improved methane yields and enhanced process performance. In order to increase the efficiency of the production system, careful consideration must be given to the choice of feedstocks, the production processes, and the legal framework for biogas production. Efforts must be focused on improving the technological and commercial efficiency of biogas to ensure good sustainability. In this context, appropriate investments and policies could play a key role in energy diversification.