Food waste can be anaerobically digested for biogas generation resulting in more sustainable waste management than using landfill, as well as providing clean energy. This paper reviews the challenges faced globally in using food waste-based biogas production for energy generation. It identifies feasible solutions for each challenge based on real-world case study scenarios and pilot plant studies, exploring their implications for Malaysia. Identified challenges and solutions are analysed under five headings: environmental (challenges: 2, solutions: 3), institutional and legal (challenges: 3; solutions: 6), economic and resourcing (challenges: 5; solutions: 9), technical (challenges: 4; solutions: 7) and social and cultural (challenges: 2; solutions: 3) categories. Key findings include that: (1) waste collection distance to the facility should be <10 km to reduce environmental impacts (as implemented in Singapore); (2) it is vital to set a proper division of labour and nationwide standards, as well as increasing food waste treatment facilities (as implemented in China); (3) installation of low cost digesters and reduced operational costs can help to tackle economic challenges (as shown in examples from China and South Korea), while initiatives to obtain a constant supply of food waste can help address resourcing challenges; (4) co-digestion and pre-treatment of food waste are crucial to avoid technical errors (as seen in China and South Korea) and (5) regular engagement with the community can help create awareness on food waste segregation (as demonstrated in the United Kingdom). Tackling the challenges within and across categories could help policymakers to improve existing waste management and renewable energy policies in Malaysia. Solutions given for each challenge emerging from this study offer important inputs to food waste-based biogas production both in Malaysia and globally
