The impact of energy efficiency measures on carbon reduction: An integrated LCA-exergy approach

In this study, the technical, environmental, and economic impacts of waste heat recovery (WHR)–based energy efficiency measures implemented in industrial facilities are evaluated using an integrated energy–exergy–carbon footprint–life cycle assessment (LCA) framework. Pre- and post-implementation scenarios are compared for three textile plants. The energy analysis results indicate a 9.8–11.7% reduction in total energy consumption, corresponding to an annual natural gas saving of approximately 4,858 MWh, while no significant change is observed in electricity consumption. The exergy analysis reveals that exergy efficiency increases from 36–41% to 44–50%, accompanied by a substantial reduction in system exergy losses. Carbon footprint calculations demonstrate a total emission reduction of approximately 981 t CO₂ per year. Assuming a carbon price of 80 € per ton of CO₂, the annual economic benefit is estimated at approximately 78,500 € per year, with a payback period of 2–3 years. Cradle-to-gate LCA results show a 9.6–11.7% decrease in Global Warming Potential (GWP), along with consistent improvements in Acidification Potential (AP) and Eutrophication Potential (EP) indicators. The findings demonstrate that waste heat recovery is a technically feasible, environmentally effective, and economically attractive energy efficiency strategy for thermally intensive processes commonly used in the textile industry.