Bøger af Kenneth Eloghene Okedu

This book discusses the topology of exergy as a measure of energy quality with regards to any type of machinery. Because exergy takes the second law of thermodynamics, it is partially destroyed in every process of energy conversion. Consequently, this book focuses on entropy creation in irreversible processes of low temperatures resulting in generation of waste heat. It also addresses ideas on thermodynamic systems and environment, considering temperature, chemical decomposition, and electric potential characteristics and imaging. Finally, the book provides a description of energy utilization expressed as energy efficiency.

This book reviews recent trends, developments, and technologies of energy storage devices and their applications. It describes the electrical equivalent circuit model of batteries, the technology of battery energy storage systems in rooftop solar-photovoltaic (PV) systems, and the implementation of second-life batteries in hybrid electric vehicles. It also considers a novel energy management control strategy for PV batteries operating in DC microgrids, along with the present state and opportunities of solid-state batteries. In addition, the book examines the technology of thin-film energy storage devices based on physical vapor deposition as well as the challenges of ionic polymer-metal composite membranes. Furthermore, due to the novel battery technology in energy storage devices, this book covers the structural, optical, and related electrical studies of polyacrylonitrile (PAN) bearing in mind the applications of gel polymer electrolytes in solid-state batteries. Since energy storage plays a vital role in renewable energy systems, another salient part of this book is the research on phase change materials for maximum solar energy utilization and improvement. This volume is a useful reference for readers who wish to familiarize themselves with the newest advancements in energy storage systems.

The grid codes require taking into account the reactive power of the wind farm/park in order to contribute to the network stability, thus operating the wind farm as active compensator device. This book gives a comparative study of stabilizing wind farms using flexible ac transmission systems (FACTS) units like the (Static Synchronous Compensator) STATCOM and the variable speed wind turbines like the Doubly Fed Induction Generators (DFIGs) during wind speed change and grid fault. Both systems can provide reactive power to the wind farms during dynamic and transient conditions. Simulation analyses were carried out in laboratory standard simulation software called power system computer aided design/electromagnetic transient including DC (PSCAD/EMTDC). The simulated results show that the wind farms could be effectively stabilized with both systems. However, the cost is reduced with the DFIGs system because, apart from generating electric power during steady state,it can also provide reactive power through its frequency converters to stabilize the wind farms without the need of an external reactive power compensation units like the STACOM.