EMERGING TRENDS IN WASTE-TO-ENERGY CONVERSION: GLOBAL TECHNOLOGIES AND THEIR APPLICABILITY IN AFRICAN URBAN SETTLEMENTS — A SYSTEMATIC REVIEW

Micheal Abimbola Oladosu*, Moses Adondua Abah, Rufus Emamoge Aso, Tamunotonye Blessing Captain, Chinedu Christian Iheanacho, Augustine Chidera Ekeleme, Olaide Ayokunmi Oladosu, Oladapo Opeyemi Bamidele, Angel Ojimaojo Ekele

ABSTRACT

Background: Rapid urbanisation across sub-Saharan Africa and North Africa has precipitated a municipal solid waste (MSW) crisis, with cities generating an estimated 125 million tonnes per year by 2024. Simultaneously, chronic energy deficits continue to undermine public health, pharmaceutical cold chains, and healthcare infrastructure. Waste-to-Energy (WtE) conversion offers a dual solution yet remains underexplored in African urban policy contexts. Objectives: This systematic review synthesises global WtE technologies, including incineration, anaerobic digestion (AD), gasification, pyrolysis, landfill gas (LFG) capture, and refuse-derived fuel (RDF), and critically evaluates their feasibility in African urban settings. Methods: A systematic literature search was conducted across PubMed, Scopus, Web of Science, and Google Scholar using PRISMA guidelines. Peer-reviewed articles, institutional reports, and policy documents published between 2020 and 2025 were screened. Thirty-one studies meeting inclusion criteria were analysed thematically. Results: Anaerobic digestion and landfill gas capture demonstrate the greatest near-term applicability given Africa's predominantly organic MSW composition (50–70%), while incineration is feasible only in high-density, economically stronger cities such as Addis Ababa and Casablanca. Emerging gasification and pyrolysis pilots in Kenya and Nigeria show promise but face feedstock heterogeneity and financing challenges. Conclusions: Targeted policy reform, decentralised WtE models, and climate financing are essential to unlock Africa's WtE potential. Integration with National Determined Contributions (NDCs) and pharmaceutical supply-chain resilience strategies is strongly recommended.

Keywords: Waste-to-energy; municipal solid waste; sub-Saharan Africa; anaerobic digestion; gasification; circular economy; energy access; urban sustainability.