Theoretical Efficiency of Pyroelectric Power Converters

In recent years, a number of power converters utilizing the pyroelectric effect have been reported in the literature, and attempts at computing their efficiency have been made. In this paper the maximum efficiency for power converters made with nonferroelectric pyroelectrics, with ferroelectric pyroelectrics having a first-order ferroelectric-paraelectric transition, and with ferroelectric pyroelectrics having a second-order transition is computed. The last two cases have been evaluated starting from Devonshire's equations, which describe the properties of ferroelectrics better than other equations used in previous calculations of efficiency.