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The extraction of energy from wind or water streams is generally accomplished by means of rotary systems. However, it is recognized (and it has been demonstrated) that oscillating wings can also be used for this purpose. A newly developed oscillating-wing wind- and hydropower generator is described. Its potential for the generation of electric power from tidal flows and high-altitude jet streams is studied using 2D Navier-Stokes simulations. Results for a single NACA0014 wing power generator undergoing non-sinusoidal pitch-plunge motion indicates a 30 % increase in power both power generated and efficiency over that for sinusoidal motion. Nomenclature a = plunge amplitude, m c = chord, m CP = instantaneous power coefficient, CPmean = time-averaged power coefficient, cp = surface pressure coefficient, d = maximum total transverse distance swept by any portion of the foil chordlin