Toward sustainable waste management in small islands developing states: integrated waste-to-energy solutions in Maldives context

Highlights

● Maldives’ unique natural and socioeconomic status cause waste management challenges.

● Context-specific solutions needed for sustainable waste management in Maldives.

● Waste management practices differ greatly between Male’ city and outer islands.

● Waste incineration in Male’ will double Maldives’ renewable energy supply.

● Decentralized anaerobic digestion proposed for outer islands to recover energy.

Abstract

Effective waste management is a major challenge for Small Island Developing States (SIDS) like Maldives due to limited land availability. Maldives exemplifies these issues as one of the most geographically dispersed countries, with a population unevenly distributed across numerous islands varying greatly in size and population density. This study provides an in-depth analysis of the unique waste management practices across different regions of Maldives in relation to its natural and socioeconomic context. Data shows Maldives has one of the highest population density and per capita waste generation among SIDS, despite its small land area and medium GDP per capita. Large disparities exist between the densely populated capital Male’ with only 5.8 km² area generating 63% of waste and the ~194 scattered outer islands with ad hoc waste management practices. Given Male’s dense population and high calorific waste, incineration could generate up to ~30 GW/a energy and even increase Maldives’ renewable energy supply by 200%. In contrast, decentralized anaerobic digestion presents an optimal solution for outer islands to reduce waste volume while providing over 40%–100% energy supply for daily cooking in local families. This timely study delivers valuable insights into designing context-specific waste-to-energy systems and integrated waste policies tailored to Maldives’ distinct regions. The framework presented can also guide other SIDS facing similar challenges as Maldives in establishing sustainable, ecologically sound waste management strategies.

Graphical abstract

Keywords

Anaerobic digestion / Waste incineration / Waste management / Maldives / Small Island Developing States / Waste-to-energy

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Acknowledgements

The authors are grateful to Nanyang Technological University (NTU), Natural Sciences and Engineering Research Council of Canada (NSERC), McGill University and United Nations Office for Project Services (UNOPS) for the financial support. The authors thank Dr. Boris Tartakovsky and Dr. Serge Guiot (National Research Council of Canada, 6100 Royal Mount Avenue, Montreal, Quebec, Canada) for the review of the manuscript.

Conflict of Interests

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

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