Sustainable electricity generation is at the pole position for global sustainable development. The purpose of this research is to develop a systematic framework for assessing sustainability of different electricity generation technologies, and present its application on Pakistan, which is a region with research gaps. Hydro and oil with a sustainability impact score of 0.59 and 0.39, respectively, were identified as the top and bottom sustainability performers. Gas, solar PV, wind, and coal scored 0.54, 0.52, 0.52, and 0.42, respectively. Gas is suggested as a bridging fuel for transition to a 100% renewable energy scenario by 2050. Contributions include formulation of a holistic electric generation sustainability assessment approach, and a sustainable transition pathway for Pakistan region to guide future policy making.