Coal is the largest source of electricity in the United States. It is also the cheapest. In 2006, coal produced 1.99 gigawatts of electricity, or about half of the nation’s energy needs. That year the United States burned just over one billion tons of coal, and about 90% of it was used for electricity.
Electricity Generation Process
Typically, coal is pulverized, or crushed into a coal dust. That dust is then burned in a furnace with a boiler. Furnace heat converts boiler water to steam. That steam then spins turbines used to make electricity.
Emissions Standards
The government currently has emissions standards for coal and other power generating facilities. Each coal facility must meet air quality standards in order to operate. To learn more about these standards, click here. IGCC, or integrated gasification combined cycle generation, is one of the most widely discussed clean coal technologies. During this process, coal reacts with steam under high pressure and heat to form a hydrogen gas, which powers a gas turbine. Exhaust from the gas turbine is hot enough to power a conventional steam turbine as well, increasing efficiency.
In the process, carbon dioxide, hydrogen, and other coal byproducts are captured so they can be used for useful purposes. To read more about IGCC, click here. Technologies are also making coal at existing plants cleaner. Refined coal technologies remove many of the impurities contained in existing coal. Techniques pioneered by several of our member companies are helping remove mercury and harmful gasses while unlocking more energy potential. To learn more about these projects, click here.
