Thermal energy harvesting device using ferromagnetic materials

A unique concept for harvesting electrical energy from thermal energy is presented. A thermomechanical actuator was fabricated using ferromagnetic material. The device converts thermal energy into mechanical energy, which can be converted into electrical energy using piezoelectric materials. Magnetic force and operating frequency were measured on the device. Results show that the current power density at Delta T=50 K is between 1.85 and 3.61 mW/cm(2). A thermal finite element analysis model is also presented to understand the influence of thermal interface, suggesting that increases of 18.5 mW/cm(2) or higher are achievable. (c) 2007 American Institute of Physics.