|Fig. 1: US electricity generation by fuel.  (Courtesy of the U.S. Department of Energy)|
US energy production has been based in four different sources for a number of years: coal, natural gas, nuclear, and renewable. Coal energy has long been the largest source of electricity for this country, followed closely by natural gas.  (See Fig. 1) In all four of these sources of energy, there are new developments in order to increase the efficiency and environmental safety of the fuels with new equipment. This paper will explore the latest technologies in coal and natural gas for energy production.
Coal energy has had developments in clean coal in order to decrease the carbon footprint of the fossil fuel thus making it more environmentally viable for the long term as coal consumption is not slowing in the US. Coal must become environmentally viable for the US to continue to produce energy with it.
In natural gas, hydraulic fracturing, or fracking, has opened numerous shale gas basins for drilling and increasing supply, thus making natural gas a booming source of energy in the US. Fracking has allowed for the US to take back its share as an energy producer for the entire world.
|Fig. 2: Oxy-Fuel Combustion. (Source: Wikimedia Commons)|
Coal consumption cannot be ignored; coal is the largest fuel source for electricity generation. The latest technology in coal burning seeks to slow environmental impacts in order to make coal viable long term. Clean coal refers to the processes in which the environmental impacts of CO2 from coal burning are reduced. This can happen in one of three ways: pre- combustion capture, post-combustion capture, and oxy-fuel combustion. Pre-combustion capture and oxy-fuel combustion seem to be the most viable options. Pre-combustion capture is the shift of solid coal into a gas and the burning of that gas; the CO2 is much easier to be captured and stored in that form.  Oxy-fuel combustion burns the coal in an Oxygen environment instead of regular air, allowing for low-cost CO2 capture very quickly.  (See Fig. 2) Both of these methods generate a cheap way to capture and dispose of CO2, thus preventing environmental problems that coal faces and allowing its long-term use as an energy source in the US.
|Fig. 3: Fracking Pump. (Source: Wikimedia Commons)|
Hydraulic fracturing, or fracking, has become an efficient way of producing natural gas in the United States, thus fueling electricity production. Huge gains in production for natural gas have been gained with fracking. With natural gas imports soaring through the roof, this new technique, developed at the turn of the millennium, allows the US to be competitive in the global energy markets.
Fracking works by pumping a high-pressure fluid through a fissure drilled in rock deep beneath the surface. (See Fig. 3) These cracks then allow for natural gas to be easily extracted from the earth.  Though there are some water pollution concerns, fracking seems to be a viable source of energy production. Furthermore, fracking seems to be able to produce jobs in other industries because of its huge supply throughout the US. 
The United States will continue to have to use coal and natural gas as two large sources of energy generation. New developments in both of these technologies have allowed for increased efficiency, lower cost, and higher environmental awareness. In coal, clean coal technologies have allowed for fewer CO2 emissions while burning, which is much better for the environment. In natural gas, fracking has allowed the US to become an extremely efficient producer of the substances, thus moving us into a competitive market with the rest of the energy-producing world. These new technologies are and will continue to be responsible for new frontiers in the energy industry.
© Gautam Krishnamurthi. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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