Hybrid Waste-to-Energy Solutions within a Circular Economy Framework Directed towards Sustainable Urban Waste Management in Ghana

Abstract

Cities in developing countries continue to struggle with mounting waste management challenges. Within a circular economy framework, energy recovery is mostly nonexistent. Against that background, this study aimed to design and assess the viability of a hybrid waste-to-energy facility for the Greater Accra Metropolitan Area (GAMA) in Ghana by 2030. The proposed plant integrates solar PV, anaerobic digestion and pyrolysis to treat unsegregated municipal solid waste. Three cases were developed for different product combinations. Material flow analysis was performed with STAN software 2.7.101. The results indicate that 1.6 million tons of MSW will be generated, to be potentially converted to 271 GWh of electricity, 6400 tons of hydrogen or 4400 tons of bio-compressed natural gas per year, along with additional products: compost, refuse-derived fuel and bio-oil. The economic indicators show that all cases are potentially viable in terms of the net present value (EUR 397 to 1030 million), internal rate of return (14–22%) and levelized cost of energy (0.11–0.18 EUR/kWh). As such, this study proves that waste to energy is a viable waste management solution for large metropolitan areas, with the potential to supply energy, alternative fuels and material products within a circular economy, though it requires the buy-in of policy makers.