A critical systematic review of MCDA/MCDM applications in bioenergy sustainability assessment: Methodological gaps and challenges for comparable decision-making

Bioenergy sustainability assessment requires decision tools capable of integrating environmental, economic, and social criteria simultaneously. Multi-criteria decision analysis and multi-criteria decision-making methods (MCDA/MCDM) provide a formal architecture for this purpose, yet their application in the bioenergy domain remains fragmented. This paper presents a critical systematic review of MCDA/MCDM applications in bioenergy sustainability assessment. A corpus of 9917 records was screened using SPECTER-based semantic scoring and rule-based signal detection. Of the 352 MCDA/MCDM studies identified, only 61 achieved full three-pillar sustainability integration, representing 17.3% of MCDA/MCDM applications and 0.6% of the broader retrieved literature. Full-text analysis of all 61 three-pillar studies reveals six recurrent methodological limitations: insufficient cross-technology comparability, inadequate dynamic carbon accounting, inconsistent indicator harmonisation and normalisation, opaque weighting procedures with implicit pillar-level bias, underrepresentation and poor formalisation of social sustainability indicators, and the limited use of formal uncertainty quantification. These limitations are not independent. Together, they prevent robust, transparent, and comparable decision-making across studies. The findings establish a structured empirical basis for the subsequent development of an integrated sustainability assessment framework for bioenergy systems.