A fluid powered electrical generator having an impellor-rotor rotatively mounted on a central support structure. A toroidal outer support structure surrounds the impellor-rotor, with the impellor-rotor including a plurality of circumferentially spaced-apart fluid dynamic blades. The outward ends of the blades are connected together by a rotor rings which is coaxial with respect to the outer support structure. The central support structure is supported within the outer support structure by stanchions or the like so as to permit a fluid stream to flow therebetween past the fluid dynamic blades. A peripheral electrical generator having a rotor element secured to the rotor ring and a stator element secured to the outer support structure produces electrical energy as the impellor-rotor is driven by the fluid stream.