By 2012, coal plants in the United States, China and India are expected to emit an extra 2.5 to 3 billion tons of carbon dioxide, according to a study cited in the textbook Contemporary Environmental Issues by TCU environmental sciences professor Michael Slattery.

Coal burning is the leading cause of acid rain, global warming, smog and air toxins, according to the book. In addition, mining coal is a hazardous job, in which many are killed or develop chronic health problems such as black lung disease, according to the book. The makeup of this sedimentary rock ranges from 40 to 90 percent of carbon, according to the book. Coal pollutes the environment when it is mined, transported to coal power plants, stored and buried.

Our world population is about 6.7 billion, according to government estimates, and it is expected to near 10 billion by 2050, increasing the world’s energy consumption. Coal helps generate half of the United States’ electricity and generates more than 20 percent worldwide, according to the book, and it is being used in record amounts.

Something can be done about the record-high amount of coal to diminish pollution in the future.

According to the book, wind power is the most economically and fastest-growing renewable energy source and is becoming a mainstream choice for our rapidly-growing electricity demand.