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The main objective of this study is to present an energy harvesting approach to scavenge electrical energy from mechanically vibrated piezoelectric materials.A mechanical energy harvester device has been developed and tested. The fundamental benefit of this mechanical device is that it can function effectively in a wide range of ambient vibration frequencies, whereas traditional harvesters are limited. A suitable conditioning circuit for energy scavenging has been proposed which can achieve optimal power stream. For controlling the power flow into the battery a circuit has been designed consisting of an AC to DC rectifier, an output capacitor, a switch mode DC to DC converter, and an electromechanical battery. An adaptive control system has been described for switching any electronics devices and maximizing battery storage capacity. Experimental results reveal that the power transfer rate can be enhanced by approximately 400% by utilizing the adaptive DC to DC converter. Various investigations on the piezoelectric harvester have revealed that the energy generated by the mechanical device can exceed the 1.4-volt barrier, which is suitable for charging capacitors in electronics devices. The findings of this study will be crucial in mitigating society's energy crisis.

This paper presents the design and execution of a solar tracker system devoted to photovoltaic (PV) conversion panels. The proposed single-axis solar tracker is shifted automatically based on the sunlight detector or tracking sensor. This system also removes incident sunlight overlapping from sensors that are inside the sunlight tracking system. The Light Dependent Resistor (LDR) is used as a sensor to sense the intensity of light accurately. The sensors are placed at a certain distance from each other in the tracker system to avoid sunlight overlapping for maximum power production. The total system is designed by using a microcontroller (PIC16F877A) as a brain to control the whole system. The solar panel converts sunlight into electricity. The PV panel is fixed with a vertical axis of the tracker. This microcontroller will compare the data and rotate a solar panel via a stepper motor in the right direction to collect maximum photon energy from sunlight. From the experimental results, it can be determined that the automatic (PV solar tracker) sun tracking system is 72.45% more efficient than fixed panels, where the output power of the fixed panel and automatically adjusted panel are 8.289 watts and 14.287 watts, respectively.

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An experimental study was conducted to study the effects of flow uniformity on vibration and power generation of a small vertical axis wind turbine (VAWT). Previous studies have confirmed that one of the sources of vibration in the turbine is due to aerodynamic forces, which are due to incident wind. Firstly, understanding vibration is essential before proceeding to the measurements. In this experiment, further understand the vibrations of the turbine in operation, the operating deflection shape (ODS) technique was used. A wind tunnel and flow conditioner were fabricated. Experimental modal analysis (EMA) was conducted, and the dynamic characteristics are gathered. The ODS was conducted for operating the turbine at different speeds, with and without the flow conditioner. Results from EMA and ODS are correlated to explain the behavior of structures. In conclusion, the flow conditioner tested did have a big impact on the response of the structure in terms of vibration up to 30% indifference, but not so much in power generated about 2% indifference.