9781422285534

INTRODUCTION N orth America has the largest coal reserves in the world. Most estimates show that they will last for more than 200 years. But coal’s role as a popular fuel in North America is changing. One reason is that, when burned, coal is relatively “dirty.” It produces more emissions, as gases and particles, than do natural gas or petroleum fuels. The emissions include carbon dioxide, a major greenhouse gas that contributes to the process of global warming. This is affecting the whole Earth—its atmosphere, oceans, soils, plants, animals, and people. In the United States, coal provides about one-fifth of all energy use, mostly as electricity, but burning it produces one-third of all carbon dioxide emissions. Burning coal also releases other polluting substances as well as harmful heavy metals such as arsenic and mercury. All of these substances have caused widespread environmental problems in the past. The coal industry is trying to change with the times, however. The latest coal-fired power plants are many times more efficient at turning coal energy into electrical energy. They also use advanced technologies, such as filters and carbon capture, to reduce pollution. And there are new ways of using coal, such as converting it into gas and liquid fuels and many other products. Supporters of coal say that it can be used in new, more flexible and less polluting ways. They argue that it can provide North America with a valuable, reliable, and plentiful natural resource for centuries to come.

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