Power Generation Technologies

Paul Breeze

• Publisher: Newnes
• Year: 2014
• ISBN:
  9780080983363
• Edition: 2
• Topic: Technology & Engineering
• Subtopic: Electrical Engineering & Telecommunications
• Index: Technology & Engineering

The new edition of Power Generation Technologies is a concise and readable guide that provides an introduction to the full spectrum of currently available power generation options, from traditional fossil fuels and the better established alternatives such as wind and solar power, to emerging renewables such as biomass and geothermal energy. Technology solutions such as combined heat and power and distributed generation are also explored. However, this book is more than just an account of the technologies – for each method the author explores the economic and environmental costs and risk factors. Each technology is covered using the same basic criteria so that comparisons between technologies can be made more easily. Those involved in planning and delivering energy – including engineers, managers and policy makers – will find in this book a guide through the minefield of maintaining a reliable power supply, meeting targets on greenhouse gas emissions, and addressing economic and social objectives.

• Provides a unique comparison of a wide range of power generation technologies from oil, coal, nuclear and natural gas, to geothermal, wind, solar, and bioenergy
• Hundreds of diagrams demystify how each technology functions in practice
• Evaluates the economic and environmental viability of each power generation system covered
• New chapters covering fast-advancing renewable and alternative power sources such as municipal waste and concentrating solar plants
• Fresh focus the evolution of traditional technologies such as natural gas and "clean coal"
• Expanded coverage of distributed power generation and CHP (combined heat and power) technologies

Chapter 1

An Introduction to Electricity Generation

Abstract

The history of the electricity industry can be traced back to the 19th century and the work of pioneering scientists of that era. The industry in its current form began to develop during the early years of the 20th century, based on fossil fuel and hydropower power stations delivering power across a hierarchical grid system. During the middle part of the 20th century nuclear stations started to provide electricity too. The industry at this stage was often built around nationalized or heavily regulated national and regional utilities that generated, distributed, and sold electricity. However, during the late 20th century market reforms were introduced in many countries with the breakup of these monolithic utilities and the creation of electricity markets. The 21st century has seen a rapid growth in new renewable forms of electricity generation and the growth of distributed generation, breaking down the hierarchical delivery model.

Keywords

history

steam engines

hydropower

hierarchical network

distributed generation

global capacity

global electricity production

alternating current

direct current

Electricity is at the root of everything that we think of as modern. In a practical sense it defines modernity. All of those adjuncts to living in an advanced society that began to appear from the end of the 19th century—electric lighting then electric motors, radio, television, home appliances, and, in the last part of the 20th century, the myriad of electronic devices that have been spawned by the development of the transistor including computers and portable telephones—rely exclusively on electricity for their operation. Their widespread use would not be possible without electricity and the complex electricity supply system that has evolved to deliver it.

Not only is electricity one of the foundations of a modern developed society, electricity is also capable of nourishing the advancement of a society. Something as simple as the availability of electric lighting can lead to enormous benefits in terms of levels of education and quality of life. In consequence, electricity supply is a key element of international development aid. Meanwhile the citizens of many less-developed nations yearn for an adequate electricity supply and all the benefits that it can bring. Ironically, most of the citizens of the world’s advanced societies take it for granted.

The industry that supplies electricity and maintains the network that allows it to be delivered to virtually any location on the planet makes up what is probably the largest single industrial endeavor in the world. At the same time, the supply of electricity is a complex operation. Electricity is not a physical commodity like steel or maize even though it is often bought and sold as if it were such a commodity. Electricity is an ephemeral energy source that must be consumed immediately after it is produced. This means that any power station that is producing electrical power must have a customer ready to use it. This careful balancing act is carried out across a network of electricity supply lines controlled by network operators whose primary job is to ensure that the balance between demand and supply is maintained at all times.

Electricity supply is also a security issue. While people untouched by modernity can still live their lives without electricity, a modern industrial nation deprived of its electricity supply is like a great ocean liner without it engines. It becomes helpless. Consequently, governments must ensure that their people and their industries are kept supplied, and national electricity supply strategies will often have security of supply as one of their main considerations.

This book is primarily about the ways of generating electricity. It does not cover in depth the means of transporting electricity and delivering it to those who wish to use it. Nor does it treat, except obliquely, the political issues that attach themselves to electricity supply. What it does attempt is to provide an explanation of all the myriad ways that humans have devised to produce this most elusive of energy forms.

The book is divided into chapters each devoted to one type of electricity generation. The explanations provided are thorough and technical where necessary, but do not resort to overly technical language where it can be avoided. Readers who are seeking a full analysis of the thermodynamics of the heat engine or the differential equations for solving the problem of turbine flow, will need to look elsewhere, but those who seek a thorough understanding of electricity generation will find it here.

The aim of this book is to provide a description of every type of power generation. Even so, there will be occasional lacunas; there is no description of magnetohydrodynamic power generation, for example, although even this obscure phenomenon does earn a brief mention in Chapter 14 on marine power generation. That aside, all practical and some still experimental means of producing electricity are included.

History of electricity generation

The roots of the modern electricity-generating industry are found in the early and middle years of the 19th century and in the work of men such as André Ampère, Michael Faraday, Benjamin Franklin, and Alessandro Volta. It was during this period that scientists began to forge an understanding of the nature of electrical charge and magnetic fields. The chemical battery that converted chemical energy into electricity had also been discovered and permitted the properties of a flowing electrical charge (an electric current) to be explored. This also allowed the development of the telegraph, the first electrical means of communication. It was Faraday who was able to establish the relationship between electric currents and magnetism, a relationship that makes it possible to generate electricity with moving machinery rather than taking it exclusively from chemical batteries. His discoveries opened the way to the use of rotating engines as a source of electrical power.

The widening understanding of electricity coincided with the development of the steam engine as well as the widespread use of gas for fuel and lighting. Lighting, in particular, caught the public’s imagination and one of the first major uses for electricity was as a source of light. In the United States, Thomas Edison developed the carbon filament that produced light from an electric current. Similar work was carried out in the United Kingdom by Sir Joseph Swan.

Some of the first rotating machines used for electricity generation were based on water wheels and dynamos. However, water was not always available where power was needed and the trend among municipal power stations, the first important type of public power plant, was often to utilize steam engines and generators. These stations were initially built to provide electricity for lighting in cites. Early plants were generally small with a limited number of customers, but the area supplied by each power station gradually grew in size. At the same time there was little standardization and supply voltages varied from place to place and company to company. Meanwhile, there was an extended debate about the comparative merits of direct current and alternating current as the means of supplying electrical power. This was not resolved until well into the 20th century.

Lighting offered the first commercial use for electricity, but it proved an insufficient foundation for an industry. What accelerated the growth of electricity generation was its use for traction power, such as electric trams for urban transport and the underground railway systems in London and Paris. These were the kinds of projects that stimulated the construction of large power stations at the end of the 19th century and the start of the 20th century.

From here the industry spread rapidly, particularly with the use of electric motors in commerce and industry. The piecemeal development of the supply industry eventually became a problem and nationalization and standardization became common during the first half of the 20th century. Ironically, the first of these, nationalization, would be reversed in many countries during the last part of the same century. By that time electricity had become indispensable.

Although its origins are in the 19th century, few would dispute the argument that the growth of the electricity industry was a 20th-century phenomenon. There is little doubt, too, that by the end of the 21st century it will have become the world’s most important source of energy. It is already starting to move into transportation with electric vehicles so that most types of energy needed can now be supplied electrically. It is worth remembering, however, that most of the key elements necessary for electricity generation, transmission, and distribution were developed during the 19th century.

Evolution of electricity-generating technologies

The development of the electric power industry can be dated from the development of the dynamo or alternator. This allowed rotating machinery to be used to generate electricity. There were two sorts of generator used in the industry initially: the dynamo, which produced direct current, and the alternator, which produced and alternating current (the word “generator” can be used for both but it has become associated with the latter). The first practical dynamo was developed independently by Werner Siemens and Charles Wheatstone in 1867 and it was through the dynamo that the electric motor was discovered. However, the dynamo became displaced in most uses by the alternator, because alternating current distribution of power proved more efficient based on the technologies available a...