by Eleni Apostolatos
Science classes introduce us to the rather abstract concept of energy—a system’s ability to do work. The world’s current energy dependency proves the basis of this physical fact; from charging our phones to powering our hospitals, energy drives humans’ daily activities. Regardless of where in the globe we stand, we all need energy to do work.
Energy use has increased considerably over the past decades, and it is predicted to continue escalating in years to come. With global warming on the radar, the stakes for finding environmentally clean sources have never been higher. One energy source in particular has captured the attention of the energy sector and has recently surged in popularity: shale gas. However, the scientific community and environmentalists alike remain divided on many key aspects of the energy source. Is shale gas the future of energy production, or is it a hazardous energy source that is not clean or safe enough for the future?
Shale Gas: The Basics
Shale gas is a natural gas that is found within a special form of sedimentary rock termed shale rock. Sedimentary rocks result from the gradual buildup of rich organic matter at the Earth’s surface over time; these rocks contain large deposits of natural gas trapped within them. Unlike common sedimentary rocks, like sandstones and limestones, shale rocks have extremely low permeability; in other words, they restrict outward gas flow. Shale gas is thus considered an unconventional gas.
Unconventional gas was previously deemed unproductive and expensive due to the number of wells that accessing a section of sedimentary rock required. Over the past six decades, two methods to obtain shale gas have resulted in the more efficient release of the firmly contained gas: horizontal drilling and hydraulic fracturing.
Horizontal drilling, as its name suggests, consists of the 90-degree turn of drill bits to drill into the rocks. It is effective by permitting contact with greater lengths of shale without demanding as many wells (1). The second method, hydraulic fracturing, is a more elaborate and controversial process. Also known as fracking, hydraulic fracturing ruptures shale rocks by forcing thousands or millions of gallons of water and other fluids into the shale formations. Sand and other chemicals are then immediately pumped into the openings to prevent the fractures from closing. The released gas flows out of the well—its path determined by whether the wells were drilled horizontally, vertically, or directionally—and is used to generate energy. The combination of fracking with horizontal drilling is generally most efficient, as it makes previously unproductive rock units prolific sources of energy.
Like all fossil fuels, shale gas is mostly composed of hydrocarbons, or carbon-hydrogen bonds. When fossil fuels are burned, the combustion reaction converts hydrocarbon molecules into carbon dioxide, water, and heat. The formation of these new bonds results in an output of energy that can then be expended for other purposes, while carbon dioxide typically dissipates into the air.
So how clean is the combustion of shale gas? Many environmentalists prefer natural gas to other fossil fuels, namely coal or oil, because it emits less carbon dioxide. Daniel P. Shrag, the Sturgis Hooper Professor of Geology and Professor of Environmental Science and Engineering at Harvard University, writes: “Natural gas has roughly half the carbon content of the average coal per unit energy, thus producing half as much carbon dioxide when combusted for heat or electricity.” He claims that “burning natural gas. . . results in a reduction in carbon dioxide emissions of nearly a factor of three” (2). Additionally, unlike other fossil fuels, such as oil, natural gas requires minimal processing in its preparation for use.
Natural Gas by the Trends
As global energy demand has grown through the years, the world has become increasingly reliant on natural gas. Global natural gas consumption has quadrupled from 23 trillion cubic feet (Tcf) in 1965 to a whopping 104 Tcf in 2009. The rise of natural gas outpaced the global rise in energy consumption; the proportion of global energy consumption that derives from natural gas rose from 15.6% in 1965 to 24% today. In a study on natural gas released by the MIT Energy Initiative in 2011, researchers found that “over the past half century, natural gas has gained market share on an almost continuous basis” (3).
One factor contributing to the rise of shale gas is its availability in many countries with high energy demands. Indeed, rock formations across the world provide the reserves necessary to support a continued reliance on natural gas use. In mid-2013, the United States Energy Information Administration (EIA) released an assessment of global shale gas resources, reporting that the estimated shale gas reserves in the U.S. and 41 other countries add up to 32% of the world’s recoverable natural gas resources (4). Of the countries analyzed for the purposes of the report, China, Argentina, Algeria, the U.S., and Canada rank as the five with the most shale gas reserves; North America has the most supply, with the U.S., Canada, and Mexico all leveling high.
According to MIT’s report, the increased use of natural gas around the globe is attributed to it being “one of the most cost-effective means by which to maintain energy supplies while reducing CO2 emissions. In a carbon-constrained economy, the relative importance of natural gas is likely to increase even further” (3). With the wide availability of shale gas, there is great potential for a transition to natural gas.
Criticisms of Shale Gas
However, the hard data on carbon dioxide emissions and worldwide trends do not tell the whole story of shale gas; some residents near fracking sites have claimed that the chemicals used in the process are contaminating their water and soil. In contrast to common assumptions, natural gas isn’t the main subject of controversy—the handling of natural gas is. Most concerns relate to the chemicals used in fracking, which can contaminate underground aquifers, polluting water and leaking into places where human activity is likely. Additionally, the contact of these toxic chemicals with fish or farming areas can prove damaging, as unknown and possibly harmful substances can enter the food chain (5). The wastewater produced, which is around 30-50% of the initial fracking fluid, can be radioactive depending on the chemicals that are injected into the rock formations (6). Many times, the composition of the fracturing fluids is kept hidden by companies that do not want to disclose this knowledge due to competitiveness (5).
For example, consider the experiences of Pam Judy, a resident of Carmichaels, Pennyslvania, who claims that shale gas operations near her home polluted her water and property with dangerous chemicals. Judy noticed that, after activity began on a shale gas compressor station built 780 feet from her family’s house, they began to suffer from “extreme headaches, runny noses, sore/scratchy throats, muscle aches and a constant feeling of fatigue.” She tells of her two children’s nose bleeds and her own “dizziness, vomiting and vertigo to the point that [she] couldn’t stand and was taken to an emergency room.” Her daughter commented that, at times, she felt as though she had “cement in her bones” (7).
To understand these symptoms, Judy performed blood and urine tests, which revealed that her body contained “measurable levels of benzene and phenol.” She then convinced the Pennsylvania Data Execution Prevention (DEP) to perform air quality studies of the organic compounds found in her yard. After a 24 hour canister air sampling of four days, the results verified the presence of “16 chemicals including benzene, styrene, toluene, xylene, hexane, heptane, acetone, acrolein, propene, carbon tetrachloride and chloromethane to name a few” (7).
A number of residents near sites handling shale gas are alarmed; many have experienced symptoms similar to the ones Judy’s family has suffered from, and others claim to be in more alarming situations. Even though it is complicated to prove causality in these cases, the conditions are strange and dangerous enough to require further analysis that protesters in different areas of the world have already begun demanding action—with “Fracktivists” having organized rallies like these in the United Kingdom, Romania, France, and Spain (8).
In response to wastewater, John H. Quigley, previous secretary of Pennsylvania’s Department of Conservation and Natural Resources, declared, “In shifting away from coal and toward natural gas, we’re trying for cleaner air, but we’re producing massive amounts of toxic wastewater with salts and naturally occurring radioactive materials, and it’s not clear we have a plan for properly handling this waste” (5). In the past, companies have disposed of the wastewater by keeping it stored in wells under impermeable rock or isolated basins, leaving it out to evaporate, or simply filtrating it to later dump it into the sea. The risk for leaks is very high and, according to some confidential studies by the United States Environmental Protection Agency (EPA) and the drilling industry, “radioactivity in drilling waste cannot be fully diluted in rivers and other waterways”(5).
Another concern with the fracking of shale gas is that methane gas can inadvertently escape during the extraction and transfer of shale gas. Shale gas contains high levels of methane gas, and methane leaks can be disastrous—as it is 10 times more potent as a climate-altering agent than carbon dioxide (6). Scientists at Cornell University investigated this question, considering the methane emissions in the production, distribution, and consumption of natural gas. They conclude that the production of shale gas causes methane to leak at as much as twice the rate of conventional gas wells (2). They explain that the leak is a result of the completion phase that finalizes fracking.
On the other hand, a number of tests managed by the EPA and the Ground Water Protection Council (GWPC) “have confirmed no direct link between hydraulic fracturing operations and groundwater contamination” (9). Additionally, an in-depth study conducted by MIT concluded that, “with 20,000 shale wells drilled in the last 10 years, the environmental record of shale-gas development is for the most part a good one” (10).
Different studies often provide conflicting results and conclusions. Some say that wastewater from fracking can contaminate water supplies easily and cause devastating medical effects, while others argue that the process is safe and that claims of pollution are a result of fear-mongering and defective science. Most argue more research must be done before an accurate judgment on the safety of fracking can be made. According to Durham University geoscientist Professor Andrew Aplin, “We need more data before we can decide whether shale gas could, or should, be part of our energy mix” (11). While some countries and regions agree with this logic and have placed a moratorium on fracking, others have already given shale gas the pass and have adapted procedures and regulations as more tests are being performed.
The Future of Shale Gas
The discovery of large shale gas reservoirs has prompted some to refer to North America as “the next Middle East” (12); the U.S.’s leadership as the innovative producer of shale gas in recent years has established it as a possible catalyzer for global energy change. The University of Pennsylvania’s Wharton School published the statement, “U.S. companies have sparked a shale gas revolution: U.S. shale gas production climbed from virtually zero in 2000 to a level where it is contributing a quarter of U.S. natural gas today” (13). The Wharton School’s claim was made in 2012. Over a third of natural gas consumed by the U.S. now consists of shale gas—and the transition into natural gas is anticipated to continue (14).
The U.S. has a number of major shale plays, including the Eagle Ford Play, which runs 400 miles from Southwest Texas to East Texas; the Bakken Shale Play in the Williston Basin, around the Montana and North Dakota area; and the Marcellus Shale Play, in West Virginia and Pennsylvania, which in July was recorded to account for 40% of the U.S. shale gas production (15). Judy’s personal anecdote refers to shale gas handling in the latter region.
In its Annual Energy Outlook 2014 projections report, the EIA estimates that the U.S.’s total natural gas consumption will increase from 25.6 trillion cubic feet (Tcf) in 2012 to 31.6 TcF in 2040. Along with consuming a greater amount of natural gas, the U.S. is also estimated to become a net exporter due to “production [levels growing] faster than use” (15). Projections indicate that the U.S. will go from being a net importer of 1.5 TcF of natural gas in 2012 to a net exporter of 5.8 TcF by 2040, with 56% of the increase in natural gas production resulting from the growing development of shale gas. According to the EIA, “Shale gas provides the largest supply of growth in U.S. natural gas supply” (16).
Through its greater reliance on natural gas and its shale gas initiatives, the U.S. has already begun prompting other countries to venture into shale gas drilling; about a dozen countries have performed experimental tests on shale gas wells, and some, such as Canada and China, have already begun to register commercial production of shale gas (17).
“The role of natural gas in the world is likely to continue to expand under almost all circumstances, as a result of its availability, its utility and its comparatively low cost,” predicts MIT’s report (3). KPMG International Cooperative, a Swiss entity, reiterates the same point in one of their publications on global energy use: “Shale gas has the potential to turn the world’s energy industry on its head. It’s abundant. It’s cheap. It burns cleaner than fossil fuels. And it’s being found almost everywhere” (18). Even though it is still early to declare with full certainty that shale gas will have larger stakes in global energy production in future years, it is safe to say that it has the potential to promote a new trend and revolutionize the energy industry. As more studies are still aiming to confirm shale gas’s benefits and ensure that properly-regulated production will not lead to negative environmental consequences, their results will be crucial in determining shale gas’s presence in the near and far future.
Eleni Apostolatos ’18 is currently a freshman in Greenough Hall.
- Blackmon, David. “Horizontal Drilling: A Technological Marvel Ignored.” Forbes. Forbes Magazine, 28 Jan. 2013. Web. Oct. 2014.
- Schrag, Daniel P. “Is Shale Gas Good for Climate Change?” Dædalus, the Journal of the American Academy of Arts & Sciences (n.d.): 72-80. American Academy of Arts & Sciences, Spring 2012. Web. Oct. 2014.
- Mcrae, Gregory Sustainable, and Carolyn Ruppel. The Future of Natural Gas . N.p.: n.p., n.d. MIT Study on the Future of Natural Gas. Massachusetts Institute of Technology, June 2010. Web. Oct. 2014.
- “Technically Recoverable Shale Oil and Shale Gas Resources: An Assessment of 137 Shale Formations in 41 Countries Outside the United States.” U.S. Energy Information Administration – EIA – Independent Statistics and Analysis. U.S. Department of Energy, 13 June 2013. Web. Oct. 2014.
- Urbina, Ian. “Regulation Lax as Gas Wells’ Tainted Water Hits Rivers.” The New York Times. The New York Times, 26 Feb. 2011. Web. Oct. 2014.
- “Between a Rock and a Hard Place: Fracking Is the Most Efficient Method for Accessing Deep Reserves.” The Report: Oman 2013. N.p.: n.p., n.d. N. pag. Oxford Business Group. Oxford Business Group, 8 Jan. 2013. Web. 25 Oct. 2014.
- Judy, Pam. “Personal Account from the Marcellus Shale.” Marcellus-Shale.us. Marcellus-Shale.us, 20 July 2011. Web. Oct. 2014.
- “Global Frackdown: World Protests Shale Gas Production.” RT News. Autonomous Nonprofit Organization “TV-Novosti”, 24 Dec. 2013. Web. Oct. 2014.
- “Executive Summary.” US Environment Protection Agency. N.p., June 2004. Web. 14 Feb. 2012.
- Brooks, David. “Shale Gas Revolution.” The New York Times – The Opinion Pages. The New York Times, 03 Nov. 2011. Web. Oct. 2014.
- Anscombe, Nadya. “Fracking for Shale Gas: Geologists Demand More Data for UK.” Editorial. Engineering & Technology Magazine n.d.: n. pag. The Institution of Engineering and Technology, June 2014. Web. Oct. 2014.
- Ng, Zhi Y. “Is North America the Next Middle East for Energy?” CNBC. CNBC LLC, 21 Mar. 2012. Web. Oct. 2014.
- “The Once and Future U.S. Shale Gas Revolution.” Knowledge@Wharton. Wharton School of the University of Pennsylvania., 29 Aug. 2012. Web. Oct. 2014.
- Kelly, Ross. “No Shale-Gas Revolution Yet for Australia.” The Wall Street Journal. Dow Jones & Company, 25 Sept. 2014. Web. Oct. 2014.
- Nickelson, Ron. “The Seven Major U.S. Shale Plays.” (n.d.): n. pag. Clover Global Solutions, 2012. Web. Oct. 2014.
- “Annual Energy Outlook 2014.” (n.d.): n. pag. U.S. Energy Information Administration, Apr. 2014. Web. Oct. 2014.
- “North America Leads the World in Production of Shale Gas.” U.S. Energy Information Administration – Today in Energy. U.S. Department of Energy, 23 Oct. 2013. Web. Oct. 2014.
- International, Kpmg. “Shale Gas – A Global Perspective.” (n.d.): n. pag. KPMG International Cooperative, 2011. Web. Oct. 2014.