Gas-Turbine Power Generation

Paul Breeze

• Publisher: Academic Press
• Year: 2016
• Print ISBN: 9780128040058
• eBook ISBN: 9780128040553
• Topic: Tecnologia e ingegneria
• Subtopic: Ingegneria elettronica e telecomunicazioni

Gas-Turbine Power Generation is a concise, up-to-date, and readable guide providing an introduction to gas turbine power generation technology. It includes detailed descriptions of gas fired generation systems, demystifies the functions of gas fired technology, and explores the economic and environmental risk factorsEngineers, managers, policymakers and those involved in planning and delivering energy resources will find this reference a valuable guide that will help them establish a reliable power supply as they also account for both social and economic objectives.- Provides a concise, up-to-date, and readable guide on gas turbine power generation technology- Focuses on the evolution of gas-fired power generation using gas turbines- Evaluates the economic and environmental viability of the system with concise diagrams and accessible explanations

Chapter 1

An Introduction to Gas-Fired Power Generation

Abstract

Natural gas is the second most important fossil fuel for generating electricity after coal. Although it has a long history as a fuel for power generation, it is only since the 1990s that its use has soared, mainly on the back of the development of the high-efficiency combined cycle power plant. These plants are cheap to build and can produce cheap electricity if the cost of gas is low. They emit less carbon dioxide than coal-fired power plants. The commercial exploitation of natural gas began during the 19th century when it was first used for lighting. Electricity generation was initially in gas-fired boilers with steam turbines but the development of the gas turbine offered an alternative route to power generation, one that has come to dominate production from natural gas.

Keywords

Natural gas; fossil fuel; power generation; gas turbine; gas boiler; steam turbine; global production; renewable grid support

Natural gas is the second most important fossil fuel for generating electricity after coal. Its exploitation as an energy source for electrical power generation dates from the early part of the 20th century. However it was in the latter part of the century that capacity accelerated alongside the development of efficient gas turbine-based power stations. The use of natural gas for power generation has continued to grow into the 21st century, particularly among the developed nations. In the United States, where the economic extraction of natural gas from shale rocks in the past decade has dramatically increased the amount of natural gas available and reduced the cost of the gas, this has been especially noticeable. Other regions are now trying to exploit the potential for shale gas, with varying success.

While cost has been one factor driving the use of natural gas for power generation, another has been climate change. Combustion of natural gas produces significantly less carbon dioxide for each unit of electricity generated than would be emitted by a coal-fired power station during production of the same unit of power. A natural gas-fired power station can be as large as a coal-fired power station and it can generate electricity continuously like a coal-fired plant,¹ making it a good substitute for the latter. Switching from coal to natural gas has therefore provided a simple means for companies to meet climate-change emission control limits more easily and for nations to achieve targets for carbon dioxide emissions.

While a switch from coal to natural gas will reduce overall emissions for each unit of power it will not eliminate them. To achieve that requires either abandoning the combustion of fossil fuel for power generation or the introduction of carbon capture and storage technologies to natural gas-fired power plants. The technologies for both carbon capture and its storage already exist but they have yet to be tested the scale of a large natural gas-fired power station. So, while power companies and some governments are promoting natural gas—with or without carbon capture—as a stage on the way to a carbon free energy economy, environmental campaigners generally consider it to be a distraction, sapping investment that could otherwise be used to develop more extensive renewable generation resources.

The recognition of natural gas as a source of energy can be traced back to around 500 BC. Natural gas seeping from the ground will often ignite to create a flame but in earlier times its significance as an energy source was not recognized. More often the flame was instead considered a sacred sign. It was in China for the first time that this seeping gas was collected and transported in bamboo pipes, then used to boil sea water and produce salt.

Commercial use of gas for energy originated in Great Britain in the 18th century although this was based on gas manufactured from coal rather than natural gas extracted directly from the earth. The modern natural gas industry probably started in the United States in the middle of the 19th century when gas was first pumped from a natural gas well and distributed for lighting. At this stage, however, long distance transportation of gas was not possible and gas was all used locally. It took the development of gas pipeline technology in the 20th century to make natural gas widely available.

Pipelines are a key technology in the growth of the natural gas industry. The cheap, easy transportation of natural gas though pipelines gives the fuel one of its main attractions. Pipeline delivery has allowed gas to be used as a source of domestic energy for both heating and cooking, as a commercial energy source, and in industrial processes. This ease of transportation has also allowed natural gas to be traded globally, like oil, and this has led to large global and regional fluctuations in the cost of natural gas over the past 30 years. Such fluctuations can have serious economic consequences, particularly for power plants that use the fuel.

The commercial electricity industry began at the end of the 18th century when electric power started to replace gas as a source of light, incidentally removing one of the main uses of gas at the time. This prompted gas companies to search for other uses for their product. One of those was electricity generation. The production of electricity from natural gas began during the first half of the 20th century with the use of gas in combustion boilers similar to those used for the combustion of coal. While this practice continues in some parts of the world, particularly where natural gas is abundant, it was the development of gas turbines for power generation that led to a dramatic rise in the global use of natural gas by the power industry. Gas turbine-based power plants, particularly combined cycle plants that add a steam turbine to exploit the waste heat from gas turbine exhausts, have much higher efficiencies than traditional boiler plants and are both cheap and quick to build. This has made then extremely attractive commercially. Piston engines fired with natural gas are also popular for smaller capacity generation.

Large natural gas-fired power stations have become an important component of the electricity supply industries in many parts of the world, particularly in the developed nations of Europe and in North America. However the arrival of renewable energy has changed the complexion of the electricity industry and with it the function of these gas-fired power stations. Their use is now being adapted to help accommodate the large volumes of renewable electricity generation that is being introduced into national grids in many parts of the world, with the natural gas plants providing back up for the intermittent renewable supplies. This renewable support duty is likely to provide a role for natural gas-fired power plants well into the 21st century.

1.1 The History of Natural Gas as an Energy Source and for Power Generation

Natural gas, the product of the fossilization of organic material in the earth’s crust, has made its presence known for millennia when gas leaking from reservoirs close the earth’s surface has ignited to create a flame bursting from the earth. The temple to the Oracle of Delphi, an ancient Greek temple on Mount Parnassus, is reputed to have been founded after a goat herd found a flame issuing from a fissure in the rock, a flame that was considered to be divine. Similar divine flames have been identified from ancient Persian and Indian religions and are probably the original source of “eternal flames” that still have symbolic meaning today in both religious and secular contexts.

It was in China that the nature and utility of natural gas was first recognized as a sou...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Chapter 1. An Introduction to Gas-Fired Power Generation
• Chapter 2. The Natural Gas Resource
• Chapter 3. Gas-Fired Power Generation Technology
• Chapter 4. Gas Turbines
• Chapter 5. Advanced Gas Turbine Design
• Chapter 6. Advanced Gas Turbine Cycles
• Chapter 7. Combined Cycle Power Plants
• Chapter 8. Microturbines
• Chapter 9. Gas-Fired Power Plants and the Environment
• Chapter 10. The Cost of Electricity Generation from Natural Gas-Fired Power Plants