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| Fig. 1: Overview of Fracking Process (Source: Wikipedia Commons) |
Fracking is short for Hydraulic Fracturing, which is a method of extracting natural gas and oil by fracturing the earth using a pressurized liquid. It is so-named because 'fracking fluid' (mainly made out of water, sand and chemicals) is injected into a wellbore at high pressures, creating cracks in the earth. Once those cracks are formed, the pressure is removed, while the additives in the fracking fluid keep the cracks open, allowing natural gas from deep underground rock formations to escape to the surface and be collected. The first commercially successful application of hydraulic fracturing was carried out in 1949. [1]
Hydraulic fracturing is clearly not a new technique. Over the past decade however, growing global demand for energy as well as instability in the Middle East, have made fracking an attractive alternative to dependence on other countries for our energy needs. Today, natural gas contributes to approximately 25.6% of total power generation in the United States. This is a significant portion of the energy resources used to power this nation- solar and wind combined barely contribute to 3% of total power generated. Clearly, natural gas is an important energy resource. In fact, it has been touted as a cleaner alternative to the burning of coal, which currently still supplies 19.7% of our energy needs. [2]
On the other hand (as of the end of 2014), we have approximately 9.8 trillion cubic meters of proven and recoverable natural gas in the United States, almost double the proven amount in 1994, due to improvements in technology and our ability to recover the natural gas. [3] To fully understand the magnitude of this number, we can do a simple calculation to estimate what that means for our energy consumption as a country. From BP's published statistics, we see that the annual consumption of natural gas in the United States was 759.4 billion cubic meters in 2014. [3] We thus have
| 9.8 × 1012 m3 7.59 × 1011 m3 year-1 |
= | 12.9 years |
This is a shockingly small number, clearly demonstrating that more research is needed to provide an accurate and transparent estimate of the natural gas resources available in the United States, so as to conclusively determine if fracking is indeed worth the hype it is currently receiving.
However, other additional benefits to fracking include the ability to produce hydrogen gas as a by-product of burning natural gas, which can in turn be tapped as an efficient and portable fuel source with a much smaller carbon footprint than the consumption of fossil fuels for energy. [4]
Taken together, all of this shows that natural gas is important to power our homes and businesses, which is why fracking (a method of obtaining said natural gas) is equally important, garnering significant attention in local and national media. However, it is unclear how much natural gas we actually have in the U.S. to sustain our ever-growing population and demand for natural gas.
The Drawbacks of Fracking
Despite its significant appeal, fracking is not without it's drawbacks. Issues of environmental health and safety have been at the forefront of the fracking debate. Just a few months ago, it was proven that fracking can and has contaminated drinking water in the United States. [5] It appears that the chemicals added to the water that is being injected into the ground as part of the process of fracking finds its way into the groundwater that eventually flows into our water supply. Environmental advocates have claimed that more dramatic changes to our water supply are occurring however, and the full impact of fracking on the health of Americans is not well understood.
At the same time, although natural gas does not produce carbon dioxide when burned, it does produce significant amounts of methane gas. Methane is a greenhouse gas, which along with carbon dioxide, can contribute to climate change. To make things worse, methane gas has been known to leak out of fracking wells into the atmosphere. [6] While researchers have shown that natural gas has between 17-27% less emission that gasoline and coal, the carbon footprint of natural gas must be addressed in order to fully combat climate change. [7]
Finally, protests against fracking have focused on the link between earthquakes and the fracking process. In Oklahoma for example, which saw fewer than two earthquakes of magnitude 3.0 greater a year pre-fracking, is now observing approximately two earthquakes of such magnitude every day. [8] Scientists have found that waste water produced as part of the fracking process was being injected back deep into the rock, causing the faults to slip, which in turn leads to an earthquake. [9]
Given the ever-growing demand for energy in the United States and our ever-shrinking fossil fuel resources, it seems likely that fracking is here to stay. However, recent results by scientists across the country demonstrating that clear drawbacks to the fracking process cannot be ignored for the short and long term health and safety of the people. To that end, further research must be done to better understand the problem at hand, so that the impact of fracking on the environment and community can be fully addressed.
© Annabel Chew. 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.
[1] D. Blackmon, "Oil and Gas Boom 2014: Happy 65th, Hydraulic Fracturing," Forbes, 18 Mar 14.
[2] C. Helman, "Solar Power Is Booming, But Will Never Replace Coal. Here's Why," Forbes, 24 Apr 14.
[3] "BP Statistical Review of World Energy 2015," British Petroleum, June 2015.
[4] J. A. Turner, "A Realizable Renewable Energy Future," Science 285, 687 (1999).
[5] A. Neuhauser, "EPA: Fracking Tainted Drinking Water, but Problems Not Widespread," U.S. News, 4 Jun 15.
[6] D. Poplawski, "Hydraulic Fracturing (Fracking) and its Effect on Global Warming," PH240, Stanford University, Fall 2014.
[7] A. Burnham et al., "Life-Cycle Greenhouse Gas Emissions of Shale Gas, Natural Gas, Coal, and Petroleum," Environ. Sci. Technol., 46, 619 (2012).
[8] R. Ferris, "Quakes Not Caused By Fracking But By Water Disposal: Study," CNBC, 19 Jun 15.
[9] F. R. Walsh III et al., "Oklahoma's Recent Earthquakes and Saltwater Disposal," Sci. Adv. 1, e1500195 (2015).
