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| Fig. 1: Simplified image explaining the mechanisms of hydraulic fracturing. (Source: Wikimedia Commons) |
The thought of the U.S. being less dependent on oil imports is arousing to most Americans. So, it is no surprise that at a time when the search for alternative fuel sources is on the rise, hydraulic fracturing, or fracking, has increased in popularity. In a simplified form, as demonstrated in Fig. 1, fracking is the mechanism in which high-pressure water is directed at a shale rock, causing the rock to fracture. A liquid, including water, chemicals and sand (the most common fracking proppant), is then injected into the rock causing gas to flow out. The proppant holds the newly formed cracks open allowing gas or oil to flow out with less resistance. Surprisingly, mechanisms similar to fracking have been around for a while, but recently this process has become considerably more prevalent because of possible economical and environmental benefits. benefits.
As demonstrated by Dean Poplawski, Stanford Class of 2016, in his ph240 2014 report on hydraulic fracturing, many scientists believe that major advantage to the increase of U.S. investment in fracking is the divergence from other fossil fuels that typically lead to higher CO2 emissions. However, recent studies, for example one put on by Klaus Hubacek of the University of Maryland, College Park, claim that the decline in CO2 emission from 2007-2013 is closely linked with the 2007 U.S. recession that lead to unemployment and drop in the volume of goods consumption. [1] Despite recent findings, there is still an evident positive outcome with decreasing the burning coal that fracking allows. If we focus solely on the CO2 emission of the combustion of natural gas compared to coal, natural gas generates half the carbon dioxide. [2] CO2 is the largest greenhouse gas associated with human activity, found to account for around 82% of human emissions including the top three sources of electricity, transportation, and industry. [3] Therefore, if we were focusing solely on CO2, would the tradeoff of replacing coal for fracking oil be beneficial?
However, there is more than just C02 to consider when thinking about our environment. The largest argument against fracking is its negative environmental impact. A major consequence of fracking is the methane exposure that happens during the fracturing. The gas that comes back through the well is usually methane, a powerful greenhouse gas that warms the environment. One- fifth of fracking devices have been found to admit methane into the environment. When released into the environment, Methane, compared to CO2, is a much more powerful greenhouse gas regarding its impact on global warming. [4] Traditionally fracking has been practiced on vertical wells; however, recent technology has allowed fracking mechanisms to be applied to horizontal wells. Despite the revenue of accumulating more resources, this new design in fracking requires a considerably larger amount of water and chemicals.
There is no clear answer to whether fracking should be permitted in the U.S. It is difficult to weigh the economic value verse the environmental impact. In looking at the main pros and cons of hydraulic fracking, there are many questions surrounding the safety and environmental impact of fracking. Although the reduction in coal usage is positive, is the emission of methane an even greater negative? Hopefully more research can be done in regards to eliminating the methane emission from wells. If progress can be made in limiting this deleterious chemical, fracking could be a promising hope to give both financial and environmental benefits.
© Abigail Lebovitz. 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] S. Zielinskin, "Recession, Not Fracking, Drove a Drop in U.S. Carbon Emissions.," Smithsonian Magazine, 21 Jul 15.
[2] K. A. Hassett and A. Mathur, "Benefits of Hydraulic Fracking," Oxford Energy Forum, Issue 91 (February 2013), p. 11.
[3] "Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2013.," U. S. Environment Protection Agency, EPA 430-R-15-004, April 2014.
[4] C. Joyce, "Scientists Track Down Serious Methane Leak In Natural Gas Wells," National Public Radio, 9 Dec 14.
