This paper considers energy harvesting using pyroelectric materials such as PZT-5A and thin-films. A simple model is used to predict the power generated based on the measured temperature of the material as a function of time. The measured and predicted results are presented and compared. In particular, the measured peak power density for a PZT-5A sample was 0.23 μWcm−2 for a maximum temperature rate of approximately 15 °Cs−1. The predicted peak power density under the same boundary conditions for thin-film lead scandium tantalate was over 125 μWcm−2. The power density is shown to be highly dependent upon the surface area and the pyroelectric coefficient, underlining the importance of maximizing these parameters.