To demonstrate the energy aware functionality and capabilities of the energy-har­vesting sensor node, a demonstration system was designed. Included in this system are further nodes with which the energy-harvesting node can communicate but which are not powered by energy harvesting and are not energy-aware. The dem­onstration consists of a four-node network comprising the energy-harvesting node, […]

To minimize the waste of harvested energy within the node, a number of energy ef­ficiency rules and guidelines have been followed during the design of the modules that make up the node. First, care has been taken with the selection of components. Capacitors have been selected for low leakage and equivalent series resistance val­ues. Diodes […]

In addition to the sensor module, the energy-harvesting node has further sensing capabilities. The CC2430 has a built-in temperature sensor that can be used to mea­sure the ambient temperature around the microprocessor. Further sensing abilities are provided by virtue of the energy-harvesting modules that have been attached. For example, a variation in the output level […]

In keeping with the modular design of the node, the desired sensing capabilities are hosted on a separate module to the main node, with a specified interface allowing the ready interchangeability of different sensors. The sensor interface standard con­sists of four connections: the microprocessor supply voltage, a sensor enable line, an ADC input channel line, […]

To enable the sensor node to be readily configured by unskilled operators, a plug – and-play approach has been taken to the interface between the energy multiplexer subsystem and the energy-harvesting and storage modules. This approach allows the system to be tailored to suit the available ambient energy and the amount of energy storage required […]

As the energy multiplexer subsystem uses a standardized interface to connect to the modules, other forms of energy sources and stores can also be integrated with the system. In addition to the harvesting and storage techniques described previously, modules have been designed that allow energy to be collected from external DC sources and primary batteries. […]

To harvest energy from the wind, a miniature wind turbine has been used to convert the air flow into electrical power. The turbine used with this demonstration system is a miniature device with 60-mm diameter blades. This produces an unrectified output with the RMS voltage varying with applied wind speed. As tests showed that the […]

To harvest thermal energy, the module utilizes a Peltier-type thermoelectric power generation device, a Tellurex G1-1.4-127-1.14 Power Generation Module. The Tel – lurex module has an open-circuit voltage of 2.8 V, and with the hot side at 150°C and a thermal gradient of 100°C across it, the device can produce 2.3W of power. As the […]