1 CHAPTER ONE: INTRODUCTION 1.1 Background to the Study The major source for production of electrical energy has been coal and natural gas which has an adverse effect on our environment and also require a large amount of capital for startup . The emergence of more environmental friendly (renewable energy) method of energy production has been able to reduce the reliability on harmful energy harvester. The most popular form of such eco-friendly energy production method are through the use of solar and wind , their usage are limited because of lack of continuous availability of solar and wind energy, they both depend of weather criteria which can be accurately unpredictable also they both require a large amount of space for installation . An alternative the aforementioned sources of electrical energy is piezoelectric energy. Piezoelectric effect is the ability for a material to produce an electrical charge in response to an applied external force . Piezoelectricity was developed by Pierre Curie and Paul Jacques in 1880 . The word was coined out from two Greek words, “piezin” means to press and “elektron” meaning an ancient source of electric charge . Piezoelectricity is the generation of electricity from a material when subjecting it to applied stress     or external mechanical energy such as pressure , vibration  etc. Piezoelectricity is also the charge stored in certain materials called piezoelectric materials (such as crystals, certain ceramics, bones, DNA and some proteins)  in response to an applied mechanical energy. When zero force is applied to the piezoelectric material, its charge are balanced (the positive and negative charges are evenly distributed). But at the application of force (tension or compression) causing a slight deformation in the lattice structure of the piezoelectric material which leads to the production of electric charge, which is accumulated at the surface of the piezoelectric material which can be tapped using a wire . Figure 1: figure illustrating the effect of various type of mechanical stress on a piezoelectric material There are two types of piezoelectric effect; Direct piezoelectric effect is the internal generation of electrical energy by the application of external mechanical stress  . Converse piezoelectric effect, the opposite of direct piezoelectric effect, which is the internal generation of mechanical energy due to the application of an external electric field   . Piezoelectric materials are materials that exhibit piezoelectric effect . They can be used as a way of converting vibrations into electrical energy that can be stored. They can be classified into two majorly I. Naturally occurring piezoelectric material: These are piezoelectric materials that can be found readily in nature. They include; belemnite, quartz, cane sugar, Rochelle salt, topaz, tourmaline group minerals, enamel, dentin, wood, bone, DNA, and various proteins.   II. Manmade crystals: They are fabricated by human using various materials of desired quality. They include; gallium orthophosphate and langasite . Piezo-polymer and piezo-ceramics are the most widely used because of its small size and light weight. They are used in high voltage and power sources, actuators, sensors . Energy harvesting (also known as energy scavenging) is the process of extracting small amount of energy that would have been lost as light, heat, vibration . Piezoelec tric material Full wave bridge rectifier Storage Device (Battery) Inverter AC load Figure 2: Piezoelectricity energy harvester block diagram A full wave rectifier is used to convert the Ac output of the piezoelectric material into a DC voltage. Inverter converts DC output from battery into AC output so as to power our devices. 1.2 Aims and Objectives The main object of this project is to build an eco-friendly electrical energy generator using the energy gotten from mechanical stress which can be used to operate AC loads with little complexity and no noise. This is to be realized by achieving the following specification objectives: I. II. Design and construction of a footstep generator using PZT 5A. Implementation of a full wave bridge rectifier. III. Implementation of inverter. IV. Implementation of digital measuring display for output voltages and battery indication level. 1.3 Significance of the Study A foot step generator is just a little application of piezoelectricity. Harnessing electricity through piezoelectricity is a clean way of generation. It is a forward reach towards the world’s research of greener technologies that are aimed at protecting the environment. Piezoelectricity has application over various fields, such as; The automobile field: Due to the emergence of electric vehicles, researches have been carried out on how to use piezo electricity as a secondary or emergency source of power for the vehicle  . The generated energy can also be used to power minor electrical appliances inside a hybrid vehicle  such as the dashboard or indoor lightening. The energy can be generated from the vehicle tyre  , car damper , car chassis. Some special electric vehicle charging ports have their floored laced with piezoelectric material which produces the energy that is used to charge the vehicle. Sports field: New age turfs and artificial fields are being built with piezoelectric materials being embedded into the turf. This harnesses the kinetic energy of the sportsmen to generate electrical energy and cater for the power needs such as lightening of the stadium. There are now jogging shoes with piezoelectric strips embedded into the sole, the energy harnessed from this strip is stored in a small battery which can be used later to charge a phone or a small appliance. Construction Field: Also the concept of piezoelectric floors has been successfully implemented in places like; Tokyo where the Tokyo station’s ticket gates are floored with piezoelectric floors which supplies power to the gate , a dance club in the United Kingdom, Club4Climate, also makes use of the piezoelectric floor concept to power 60percent of the clubs power needs , a company in Israel, Innowattech, makes use of the piezoelectric concept beneath the road surface and covering it with layers of asphalt which generates energy good enough to be fed to the grid . Other domestic application include buzzer. 2 References  S. PATTNAIK, "Design and Analysis of of Piezo-wheel for electric vehicle," Nagpur, India, 2014.  S. Z. A. R. Y. T. 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