From Linear Production to Net-Zero Systems: Circular Economy Strategies in Manufacturing

Chukwuma Godfrey Ono¹, Charles Chikwendu Okpala², Ezekiel Oluwadamilare Akintona³

^1,3Lecturer, Industrial/Production Engineering Department, Nnamdi Azikiwe University, Awka, Nigeria.

²Professor, Industrial/Production Engineering Department, Nnamdi Azikiwe University, Awka, Nigeria.  

Abstract

Manufacturing systems face increasing pressure to reduce greenhouse gas emissions while sustaining productivity and economic competitiveness. Circular economy strategies are widely promoted as a pathway towards net-zero manufacturing, yet their actual sustainability benefits remain unevenly quantified, especially when circularity metrics are disconnected from energy and emissions outcomes. This study addresses this gap through the development and application of a data-driven Hybrid Circularity–Net-Zero Assessment Framework that integrates operational manufacturing data, material flow-based circularity indicators, and life-cycle–oriented sustainability accounting. With the application of representative industrial production data and scenario-based analysis, the framework evaluates linear production alongside multiple circular strategies, including closed-loop recycling, remanufacturing, product life extension, and combined circular configurations. The results reveal that while all circular scenarios improve material circularity, their net-zero performance varies significantly. Higher-order strategies that preserve product integrity, especially remanufacturing and life extension deliver the largest reductions in life-cycle greenhouse gas emissions, primarily through avoided primary material production. In contrast, recycling-focused strategies may increase process energy use while still achieving net emissions reductions when upstream impacts are considered. The findings demonstrate that circularity gains alone are insufficient indicators of sustainability and highlight the importance of integrated, data-driven evaluation to reveal trade-offs and prioritize high-impact interventions. Through the linking of factory-level data to system-level environmental outcomes, the study reframes circular economy implementation as a net-zero system design challenge and provides a replicable analytical pathway for the alignment of manufacturing circularity strategies with verifiable sustainability and climate objectives.    

Keywords: Circular economy, Net-zero manufacturing, Industrial decarbonization, Data-driven sustainability, Circularity metrics, Digital manufacturing, Life-cycle assessment

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