This project will study ways of substantially increasing the efficiency of a novel way of generating electricity from the wind. Flag-like elements (termed piezoelements) composed of flexible piezoelectric materials will be positioned in the wind, which will cause the element to flap in a manner similar to a waving flag. The stresses induced in the piezoelectric material by the flapping will generate a voltage (due to the piezoelectric material properties) between the electrodes positioned on the surfaces of the piezoelement and thus electrical power in a connected load. Three specific areas of research will be addressed to increase the overall generation efficiency (output electrical power divided by input wind power). First, the geometry (length, width, thickness, and stiffness) of the piezoelement will be optimized in order to obtain the maximum flapping amplitude (and thus conversion of incident wind energy to strain energy in the piezoelectric material). Second, several different flexible piezoelectric materials will be characterized to find the material that most efficiently converts strain energy in the material into electrical energy. Third, a variety of interface electronic circuits whose function is to convert the voltages generated by the piezoelement into the amplitudes and frequencies needed for a particular application will be studied in order to develop a very efficient interface circuit. The proposed scheme is mechanically simple and potentially low cost. The amount of power that could potentially be generated will scale with the size and number of piezoelements placed in the wind. This source could supplement existing sources such as solar cells, batteries, and gasoline generators in military, industrial, and consumer environments and for temporary emergency power.
