Investigation of temperature gradient between ambient air and soil to power up wireless sensor network device using a thermoelectric generator

This paper proposes a study of an energy harvesting system for powering wireless sensor network (WSN) devices. The thermal energy harvesting system used is based on the thermal energy source between ambient air at the soil surface with five depth levels. Measurement was taken for 46 days in a garden area located in Melaka, Malaysia. A feasibility study of soil temperature measurement to obtain a temperature gradient can be used for harvesting by using thermoelectric generators (TEG) modules. Then, the efficiency of TEG with several different configurations based on temperature gradient data has been tested in the laboratory. The results revealed that the depth of soil 6 cm between sensors 1 and 3 will gave the best representation of level average temperature different around 1 ℃. Based on the temperature gradient data, the combination of three TEG SP1848 in a series connection with DC-DC step-up circuit DC1664 will produce an optimum voltage output of about 3 V. This output voltage is enough to operate low power IoT device derived from thermal energy

A New Method for a Piezoelectric Energy Harvesting System Using a Backtracking Search Algorithm-Based PI Voltage Controller

This paper presents a new method for a vibration-based piezoelectric energy harvesting system using a backtracking search algorithm (BSA)-based proportional-integral (PI) voltage controller. This technique eliminates the exhaustive conventional trial-and-error procedure for obtaining optimized parameter values of proportional gain (Kp), and integral gain (Ki) for PI voltage controllers. The generated estimate values of Kp and Ki are executed in the PI voltage controller that is developed through the BSA optimization technique. In this study, mean absolute error (MAE) is used as an objective function to minimize output error for a piezoelectric energy harvesting system (PEHS). The model for the PEHS is designed and analyzed using the BSA optimization technique. The BSA-based PI voltage controller of the PEHS produces a significant improvement in minimizing the output error of the converter and a robust, regulated pulse-width modulation (PWM) signal to convert a MOSFET switch, with the best response in terms of rise time and settling time under various load conditions

Harvesting vibration energy by employing piezoelectricity and electromagnetism

1 online resource (141,16 unnumbered pages) : colour illustrations, charts (some colour), graphs (some colour)Includes abstract.Includes bibliographical references (pages 122-136).Many energy technologies have their environmental footprint. However, energy from renewable sources does not. Venturing into green ways of producing energy is the order of the day. This project aims at generating energy from vibrations created in pedestrian movement through the joint application of piezoelectricity and electro-magnetism. Harvesting vibration energy through these two methods would be to harness what would otherwise be a largely unharnessed energy source. Piezoelectricity offers an advantage over other generation schemes by generating electricity “intrinsically,” obviating the need for moving parts and mechanical complexity. Electro-magnetism, on the other hand, does involve moving parts but is much less complex compared to other renewable energy technologies. This project dwells deeply into weighing the pros and cons of employing these two technologies and assessing whether, together, they would be a good contender to other existing renewable energy sources in the context of being a feasible micro-power generator