Towards sustainable electricity generation: Evaluating carbon footprint in waste-to-energy plants for environmental mitigation in Iran

Abstract

The environmental impacts of municipal solid waste have become a critical issue in Iran due to rising waste generation and limited waste treatment methods. From a global warming perspective, in 2018, Iran was the seventh-highest greenhouse gas emitter in the world. An implementation should demonstrate that it is possible to estimate the environmental impact of climate change. A simple carbon footprint estimation model for waste-to-energy power plants with a life cycle assessment using the 2006 Intergovernmental Panel on Climate Change (IPCC) guidelines is presented in this study. For this purpose, first the system boundary is determined. Then, the total emissions of each part within boundary are identified in terms of total greenhouse gas emission (and expressed in mass of carbon dioxide equivalent). In conclusion, the carbon footprint of generating one kWh of electricity is estimated. The final emission of the Tehran power plant is calculated at 24.46 ktCO2eq/year. Thus, the carbon footprint is estimated to be 1351.94 g CO2eq/kWh. Key parameters that affect carbon footprint are divided into two groups: emission parameters and electricity generation parameters. The sensitivity analysis of effective parameters showed the distance travelled and weight of waste transported during waste transportation, the fossil carbon content in waste composition has the highest effect on carbon footprint. The study shows a 1.2-fold difference between the carbon footprint of two current scenarios of waste treatment: landfill and waste-to-energy plant. The life cycle emissions of landfills exceed of waste-to-energy plants, indicating that these systems can contribute significantly to addressing the current environmental challenges. Additionally, they offer advantages in terms of electricity generation.