Volume 5, Issue 3-4 -

Exponential growth in computing, wireless communication, and energy storage efficiency is key to allowing smaller and scalable IoT solutions. These advancements have made it possible to power devices from energy harvesters (EH) and explore other energy storage solutions that can increase the lifetime and robustness of IoT devices. We summarize current trends and limits for the current paradigm as the basis of our forecast. The trend shows that conventional ceramic capacitors are sufficient for energy storage for today’s EH powered wireless IoT devices and that in the future, IoT devices can either perform more advanced tasks with their current volume or be shrunk in size.

Vibrational energy from intermodal transport system can be recovered through the application of piezoelectric energy harvesting system. The intermodal vibration sources are passenger cars and freight trucks moving on streets and highways, trains moving on railway tracks and planes moving on airport runways. However, the primary limiting factor of the application of the piezoelectric energy harvesting system has been the insignificant power output for power storage or to directly power electrical device. A special nano-mixture coating is developed to enhance the energy harvesting capability of the conventional piezoelectric material. This research investigates the impact of the nano-mixture coating on the power output. The experimental results of the nano-mixture coated system show substantial and explicit improvement on the power output. Alternative geometrical designs, trapezoidal and triangular are explored in anticipation for improved power output. But the rectangular energy harvester demonstrates better power harvesting capability. The results presented in this paper show the potential of the nano-mixture coating in power harvesting from intermodal transport system.

A wide bandwidth energy harvester is designed with the purpose of operation under multiple excitations, where the excitation frequencies are generally incommensurate and probably spectrally close to each other. Owing this wideness of bandwidth to the nonlinearity of the circuit escalates the jeopardy of chaotic behavior while the circuit is exposed to multiple energy sources. In this study, the recently introduced Duffing based energy harvester is analyzed under multiple excitations and finally, a safe margin is calculated to avoid tumultuous behaviors which may affect adjacent sensitive electrical systems. The mathematical analyses given in this paper can be generalized to other types of nonlinear resonators.

We evaluate the storage performance of an integrated energy harvesting and storage system using a thermoelectric generator (TEG) and an organic energy storage device. The power generated by the TEG is obtained by varying the temperature of the heat source on the bottom surface of the TEG while keeping the opposite surface at a constant cooling temperature. The difference in temperature gradient (Δ T) increases the power generated by the TEG. Capacitance-voltage measurements were performed on the organic storage device to evaluate the storage capabilities of the embedded storage elements, CdS nanoparticles. The objective is to assess the possibility of the integrated system and evaluate the effectiveness of the storage device. Voltage, current and power density values are determined and compared for different load resistance. The results revealed that for the 100 Ω load resistor, the voltage across the capacitor was the maximum at a lower temperature gradient with a charge density of 5.14×10−3Cm2$5.14 \times 10^{-3} \frac{C}{m^2}$.