UKRAINE Becoming the largest Eastern European nuclear power plant in 1995 following the completion of its sixth reactor , Zaporizhia is located in Enerhodar , Ukraine , on the banks of the Kakovka Reservoir . Zaporizhia is responsible for generating approximately 20 % of Ukraine ’ s entire electricity supply , from six pressurised water reactors ( PWRs ). All six units were completed in a nineyear period ( 1984 to 1995 ). Following an application made by Energoatom - the nuclear power company operating the plant - the first two units are currently being assessed for modernisation efforts in an effort to extend their operational lifespan .