This article compares pyrolysis, gasification and incineration waste-to-energy technologies based on life cycle assessment (LCA) and case studies of commercial plants. The study concludes that gasification and pyrolysis have better environmental performance than incineration, but modern incineration is more valuable due to its flu gas cleaning effectiveness, ash recycling, and CHP cycle usage. The article also highlights the importance of waste quality, energy efficiency, and efficient residues management for achieving sustainability.