An apparatus for generating electrical energy may include; a first electrode, a second electrode spaced apart from the first electrode, a nanowire which includes a piezoelectric material and is disposed on the first electrode, an active layer disposed on the first electrode, a conductive layer disposed on the active layer, and an insulating film disposed between the conductive layer and the nanowire, wherein the nanowire and the active layer are electrically connected to each other. A method for manufacturing an apparatus for generating electrical energy may include; disposing a nanowire including a piezoelectric material on a first electrode, disposing an active layer, which is electrically connected to the nanowire, on the first electrode, disposing an insulating film on the nanowire, disposing a conductive layer on the active layer, and disposing a second electrode in proximity to the nanowire and substantially opposite to the first electrode.