a diffuser augmented wind turbine assembly 10 according to the invention and rotatably mounted on a conventional support pole 11 so it can be moved by a fin 12 to compensate for shifting wind directions the assembly has an outer diffuser shell 15 within which can be seen a blade and rotor drum assembly 16 as described in greater detail below fig2 shows assembly 16 in greater detail and as having an outer cylindrical rotor drum 18 with turbine blades 19 extending radially therein and preferably integrally formed with the rotor drum the assembly can be cast or of welded construction if made of metal e g aluminum or integrally injected molded if made from a composite material strengthened by glass carbon or similar reinforcing fibers though six blades are shown the number of blades can be selected by the designer multiple blades such as five or six are preferred as they improve turbine efficiency as well as increasing the rigidity of assembly 16 turbine blade strength and stiffness is significantly increased by the fixed support of the blades on the drum the assembly is stable and balanced and can be safely operated at high wind speeds encountered in storm conditions for smaller wind turbine assemblies which typically operate at high rotation speeds centrifugal force compressively loads the blades making them less prone to fatigue failure fig3 is a sectional side elevation of one embodiment of assembly 10 and shows assembly 16 as rotatably mounted within diffuser shell 15 the diffuser shell is preferably molded from a strong composite material and has an outwardly divergent section 21 which merges with outwardly stepped ring shaped inner and outer cylindrical support sections 22 and 23 an end.