Thermal Energy Harvesting Wireless Sensor Node in Aluminum Core PCB Technology

This paper reports the design of a self-powered telemetric wireless sensor node for temperature measurement. The device is realized with a conventional off-the-shelf thermoelectric generator as a power source. It is sandwiched between two aluminum core printed circuit boards (PCBs). One board is exposed to the heat source and has the role of a heat collector, whereas another one with the mounted low profile heatsink acts as a heat spreader. Electronic components of the node are placed on the inner surfaces of the boards. Implemented step-up circuitry is accommodated to achieve stabile cold boot of the node at a low temperature difference between its hot side and ambient (less than 15 °C), even when it is in thermally inefficient position. Operational autonomy of the node in the absence of the heat source is extended by 30% comparing with the common step-up circuitry implementation. The aluminum core PCBs provide node simplicity and compactness, with small overall dimensions.