The myth and the reality of energy recovery from municipal solid waste

Abstract

Background: Any manner of development can be sustainable only if the waste generated by it is not allowed to accumulate but is fully reused/recycled/recovered. Among the strategies to attain this goal have been the attempts to recover energy from municipal solid waste (MSW). About 60% of MSW is carbonaceous, consisting of materials which can either be biodegraded into fuels like methane or incinerated, thereby generating utilizable energy. MSW also contains several components-like metallic scrap and glass pieces-which can be reused or recycled, thereby achieving energy conservation. Given these attributes, MSW appears to be a potential source of energy and resources. Indeed, this belief that MSW is usable if only we try sincerely enough to do so prompts most of us to keep generating much more MSW than is warranted. But how realizable really is the energy potential of MSW? What perils loom into view when we actually set out to utilize MSW as an energy source? The present study addresses these crucially important questions. Methods: The work is based on a critical content analysis of the prior art. Results: The generation of MSW has consistently outpaced the world's efforts to dispose of it cleanly, and the energy (and material) recovery from MSW is easier said than done. In most instances, what is technically feasible is economically unfeasible. And what is economically feasible-such as setting the waste on fire as is often done in developing countries-is exceedingly harmful to the environment and the human health. Measures such as sanitary landfilling and incineration create as many new problems as the old ones they solve. Moreover, despite the use of these less-than-adequate technologies, a major portion of MSW generated in the world lies untreated. Conclusions: As the MSW output is expected to double by 2025, this situation is only set to become worse. Rising tides of E-waste would compound the problem even further. Hence, enormous stress should be put on the reduction of MSW generation by controlling wanton consumerism and wastage, rather than continuing with it in the false hope that technology will soon provide a magical solution and eliminate the problem.