Incineration, pyrolysis, and gasification during plastic waste treatment are inevitable to reduce the volume of landfilled plastic waste and recover energy; however, they cause severe carbon emissions. We show that the current practices of plastic waste-to-energy will significantly impact carbon neutrality. Various energy recovery systems, such as combined power cycles and fuel cells, were modeled to evaluate the power generated and CO₂ emitted from treating the current and projected plastic waste by 2050. The CO₂ emissions from plastic waste-to-energy systems are higher than those from current fossil fuel-based power systems per unit of power generated, even after considering the contribution of carbon capture and storage. Power generation using plastic waste will significantly increase by 2050, and therefore, we suggest technologies required for achieving carbon neutrality.