A bidirectional (oscillating) air flow is central to energy conversion from wave to wire in an oscillating water column based wave energy plant. Several classes of bidirectional turbines, which operate with such an oscillating flow, have been designed and tested with limited efficiencies. A topology which uses fluidic diodes in conjunction with unidirectional turbines is shown to significantly improve the efficiency. The design and test results from several fluidic diodes for such an application are discussed. It is shown that a combination of a fluidic diode and the unidirectional turbine can achieve a very high impedance to reverse flow while having a high efficiency in the forward direction, over a wide range of flow coefficients. Copyright © 2011 by ASME.