By Madison Hinshaw, Communications Editorial Intern in Spring 2012.
This just in: Despite the coal industry’s misleading commercials, coal no longer provides 50 percent of all energy in the U.S.!
The U.S. Energy Information Administration recently released data showing that coal’s share of total monthly generation fell below 40 percent in November and December 2011 and the combination of a mild winter and a decrease in natural gas prices might be the leading contributors.
Due to the warm trend in this year’s winter, natural gas prices have significantly dropped, which is allowing generators in many states to increase the share of natural gas-fired generation and cut coal’s share of electricity generation.
There are three types of natural gas generation: the steam boiler, the gas turbine and the combined-cycle. The combined-cycle, most often used in the U.S., uses one or more gas turbine generators complete with heat recovery steam generators to capture heat from gas turbine exhaust. Steam that is produced in the heat recovery generators is used to produce additional electricity.
Since the natural gas combined-cycle units are proven to be more efficient because of the higher heat output than coal and fewer carbon dioxide emissions, the decreasing prices are providing a competitive threat to coal-fired plants throughout the U.S.
According to the EIA, total electricity generation was down 7 percent from December 2010 to December 2011, and coal-fired generation fell by 21 percent. Despite these declines, natural gas generation rose by 12 percent providing enough hope for cleaner energy in the near future.