The Renewable energy-Food processing-Sustainability Nexus: A PRISMA review of innovations, sustainability metrics and indicators

Renewable energy-based innovations and technologies play a crucial role in reducing postharvest losses and enabling low-carbon food processing, but their sustainability assessments remain fragmented and inconsistent due to variations in evaluation metrics. This review compiles studies on renewable energy–based food processing, including solar, photovoltaic, solar thermal, and hybrid systems. It highlights that most evaluations focus on technical and environmental performance, while economic, governance, and social aspects are less consistently addressed, often reported only qualitatively. Based on reported indicators, a five-pillar conceptual framework is proposed to organize sustainability assessment across technical, environmental, governance, economic, and social (TEGES) dimensions. The framework shows how sustainability indicators can be systematically structured from design and testing to modeling and implementation stages. A key contribution of this study is the introduction of proxies for governance and social sustainability, quantifiable factors like safety, usability, and ease of maintenance, that allow for early evaluation of governance and social significance even during laboratory testing. The synthesis highlights the need for standardized sustainability reporting by using consistent boundaries, functional units, and contextually relevant metrics. By establishing a structured conceptual framework, this work enhances the methodological foundation for integrated, transparent, and policy-relevant sustainability assessments within renewable energy–based food systems, aligning research methodologies with international reporting standards such as ESG and the Sustainable Development Goals (SDGs). Future research should focus on automating and standardizing sustainability assessments, as each metric links to a specific value. This will enhance the credibility and accessibility of evaluating the climate and sustainability impacts of renewable energy innovations in food processing, ultimately supporting sustainable green funding and food production.