From the Foreword by Dr Valmond Ghyoot, Emeritus Professor of Real Estate, University of South Africa: ‘The valuation profession, the legal profession, property industry participants in general and students will welcome publication of this book. Investors, environmental groups and affected property owners will find essential information for use in their decision-making, development objections and claims. My hope is that [it] will provide answers where required and that it will help to improve the professional standard of valuations and appraisals internationally. I trust that it will also raise the standard of testimony in damages cases. If so, the editors and contributors will have succeeded in documenting the state of the art in this relatively unexplored terrain.’ As a reference source, this book will help quantify the negative impacts on property values of high voltage overhead transmission lines, cell phone towers, and wind turbines. It gives a modern perspective of the concerns property owners have about the siting of industrial structures used to transmit or generate various forms of energy and how these concerns impact on property values. Studies reveal concerns the public have about devices and structures that emit electromagnetic fields (EMFs) due to their potential health hazards. . Despite some research reports suggesting there are no potential adverse health hazards from high voltage overhead transmission lines (HVOTLs) and towers, there is still on-going concern about the siting of these structures due to fears of health risks from exposure to EMFs, changes in neighbourhood aesthetics and loss in property values. The siting of wind turbines is also receiving community opposition due to noise, light flicker, aesthetic concerns, and loss in property values. The extent to which such attitudes are reflected in lower property values is not well understood. Towers, Turbines and Transmission Lines: Impacts on Property Value outlines results of studies conducted in the US, the UK, Australia and New Zealand and offers guidance to valuers as well as to property/real estate appraisal students and property owners around the world. The book provides defensible tools that are becoming widely accepted to assess the effect that these environmental detriments have on property prices.

Excerpt from Transmission Towers: Being a Reprint of a Paper Read by E. L. Gemmill, Chief Engineer of the Transmission Tower Department of Blaw-Knox Company, Pittsburgh, Before the Engineering Society of the Same Company It is only within the last twenty-five to thirty years that it has been considered advisable to carry overhead electric power transmission lines on anything else than wood poles. But with the ever increasing tendency to concentrate power house units, and consequently to make fewer and larger installations, spaced farther apart, it has become necessary to transmit electrical energy over greater distances. This, in turn, has made it advisable to set a higher limit for the voltage at which the electrical energy will be conveyed from one point to another, in order to reduce to the lowest possible minimum the loss in transmis sion. The using of these higher voltages has, of course, brought in its train the necessity of making more careful provisions for supporting the conductors by means of which the electrical energy is transmitted from one point to another. Naturally, the first change made in the general scheme in vogue was to place the conductors farther apart, which necessitated the use of better cross arms for supporting them. At the same time it was also imperative that, with increased voltage, more clearance be allowed between the ground and the lowest conduc tor wires under the worst possible conditions of Operation. This could best be accomplished by making the supporting structures higher. So long as the wires were kept only a short distance above the ground, the wood poles made an ideal support for them under ordinary conditions; but when higher supports had to be considered, transmis sion line engineers began looking about for other supporting structures which would lend themselves more readily wall the varying condi tions of service. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.

Lightning is known to be a major cause of outage in power systems. It may result in damage to equipment, high repair costs, and loss of revenue to utility companies. The most vulnerable component of a power system to lightning is the power transmission line system. Transmission lines expand over hundreds of kilometers and are exposed to lightning discharge. When a lightning strike directly hits either the top of a transmission tower or the ground wires, surge waves are generated that flow through the tower structure that has been hit and propagate to adjacent towers. This leads to an increased voltage difference across the string of insulators that may lead to a backflashover. Backflashover may occur when the voltage difference on the string of insulators exceeds the withstand of the insulators due to a lightning surge and it is the main outage mechanism. There is a significant need in the power system community for the accurate electromagnetic transient (EMT) analysis of lightning discharge phenomena through complex power installations such as transmission towers and their grounding system. The tower-footing grounding systems consists of long conductors, in different shapes and arrangements, buried in either homogeneous or stratified ground to obtain the lowest tower-footing grounding impedance. Moreover, the impedance of the tower's structure contributes to the total impedance of the system when subjected to lightning surges. Currently, existing simulation tools make various approximations in the process of lightning analysis that result in modeling inaccuracies in many important practical scenarios. Such errors make unreliable predictions about the failure rates of the system resulting in costly power outages.In this thesis, simulation models are developed for the determination of the response of typical arrangements of grounding electrodes and transmission towers subjected to lightning and calculate the impedance of these structures over the frequency range of interest in lightning studies. Time-domain macro-models will then be developed that are compatible with EMT-type simulators (such as PSCAD/EMTDC) and enable the calculation of voltages along the tower structure considering several geometric factors and ground parameters. The objectives of this research are to accurately estimate the overvoltages/surge in the trans-mission tower, and to develop a model for the prediction of backflashovers. The developed model will significantly improve the accuracy of EMT analysis of lightning discharge and its impacts on complex power systems.