Natural gas extraction technologies – such as hydraulic fracturing- are not new. However, “fracking”, the shorthand term for hydraulic fracturing, will likely become a commonplace and far-reaching term in the public imagination–and soon. Why?
It is currently estimated that around 2.5 million wells have been treated with fracking processes worldwide. Furthermore, fracking technology is credited with adding approximately 9 billion barrels of oil and 700 trillion cubic feet of natural gas to the tally of US reserves. Consider that a single barrel of oil is worth $100 on international markets. Thus, the extraction of these reserves would see the US surpass Saudi Arabia as the world’s largest fossil fuel producer.
Combined with volatile global prices for energy, demand for relatively cleaner energy, and a decline in conventional gas deposits, natural gas has entered center-stage as an attractive energy source. Though the first fracking processes were developed in the late 1940s by Stanolind Oil, the practice has only lately seen rapid expansion and is increasingly used throughout the world. However, the practice of “fracking” itself is a matter of intense controversy.
As the prevalence of fracking continues to accelerate, more and more people are asking questions. How will fracking affect our economy? Our job market? Our clean air and water? How does fracking affect my life? Finding answers necessarily begins with an understanding of fracking technology. We must first and comprehensively answer the question, “What is fracking?”
Fracking is a procedure used to stimulate wells that have stopped producing fluid or would not normally produce fluid under standard drilling procedures. Although this fluid is most commonly natural gas, fracking can be used for the extraction of a multiplicity of fluids, including oil and water.
While many people may imagine oil or gas reserves as giant underground “lakes” of gas, this is not the case. A more accurate image is that of an underground “sponge”. Natural gas reserves are large underground rock formations saturated with gas. During normal drilling, a central wellbore is drilled into the formation and fluid flows through the rock and up the wellbore.
However, certain types of rock are far less porous and less permeable such that while gas may be present, it is impossible for it to flow through the rock to reach the wellbore. This is where fracking comes in.
The Fracking Process
The purpose of fracking is to create space in the rock formation for gas to flow through in order to reach the wellbore. In order to do this, fluid is pumped down the wellbore at extraordinarily high speeds and pressures. When the fluid pressure overcomes the confining force of the surrounding rock, the rock fractures, allowing gas to begin to flow through the cracks and up the wellbore.
Anatomy of a Drilling Rig
The area used for an oil rig and entire fracturing site typically covers about 6 acres, while the drill pipe extends between 4,000 and 8,500 feet below ground to reach the natural gas reserve below. In some cases, once the pipe has penetrated the reserve formation, lateral drilling is then conducted to extend the pipe 3,000 to 5,000 feet. This technique is called horizontal drilling and has seen increased use in conjunction with fracking in the last decade. As the main wellbore is encased with layers of piping and cement, detonation of small explosives or perforating guns is used to blast holes through the casing. These perforations allow the high-pressured pumping of fluid through the well casing, fracturing the surrounding rock and releasing the trapped gas reserves. Drilling rig sites thus contain large wells that store the water supply necessary for the extraction, a pit for wastewater, a drill pipe gilded by steel and cement, and generators.
Another critical part of the process is the fracking fluid. Fracking fluid is generally made up of three main components: water, proppant, and chemical additives. Water makes up the vast bulk of the fluid, carrying relatively small amounts of the other two components.
Proppant is present to maintain the structural integrity of the well. Proppants are small granular materials that flow into and partially fill the cracks. Essentially, these materials “prop up” the well and help keep the fractures open. Common proppants include materials like sand, glass beads, plastic pellets, and ceramics, with sand being the most common.
Chemical additives make up the third component of fracking fluid. Small amounts of chemicals are added to the fluid to serve specific purposes. A major goal of additives is to control the flow properties of the fluid. Added chemicals interact with the water and allow engineers to manipulate factors such as the viscosity and flow speed of the fluid to effectively fracture each unique well. Other goals of chemical additives include the prevention of build up, fouling, and corrosion of metal pipes used in the drilling process. While the precise mix of additives is unique to the drilling company, its engineers, and the specific well site, a typical mix may include components such as: an acid, an antibiotic, a corrosion inhibitor, a friction reducer, a gelling agent, a scale inhibitor, and an oxygen scavenger.
Points of Debate
The global economic landscape for energy has been wholly reconfigured, in large part due to the possibilities that fracking technologies offer. Because it is no longer difficult to extract tremendous but previously inaccessible deposits, the so-called “peak oil” (or stagnation of fossil fuel production declared in 2005), is far less alarming. Markets are shifting from traditional players in OPEC to North America, Brazil, and Australia. But they may very well shift back. There are widespread concerns that have spawned a growing anti-fracking movement involving what could be a wholesale reconfiguration of environmental landscapes. As we move forward, it is vital that the benefits offered by fracking technology be weighed against the risks and concerns.
1) Cleaner Energy: natural gas boasts less carbon emissions than other widely used fossil fuels such as coal and oil and as such, may be used as a “transition fuel” between traditional fossil fuels and non-carbon based alternative energy.
2) Energy Independence: hydraulic fracturing has the potential to greatly improve the energy independence of nations in possession of extensive shale gas reserves.
3) National Security: diversification of fossil fuel suppliers around the world would decrease dependence on the oil supplies of Middle Eastern nations with potentially volatile political situations.
4) Economic Growth: the rapid expansion of the natural gas industry made possible by fracking creates jobs and adds to economic growth and prosperity.
1) Clean but not clean enough: relying on natural gas as a “transition fuel” may only delay alternative energy research that could lead to the development of a carbon free energy economy.
2) Water: fracking may strain limited water supplies through high volume usage and/or potential pollution.
3) Potential health effects: adverse health effects, that may be related to fracking processes, have been reported or observed in close proximity to drilling operations.
4) Land use: oil and gas companies exercising mineral rights may devalue or deface land whose surface rights are owned by private citizens.
5) Lack of disclosure of chemicals: when complete lists of fracking chemicals are protected as intellectual property, regulation of harmful chemicals and environmental hazards may be inhibited.
6) Regulatory Exemptions: related to the above concerns as well as balancing historical federal regulatory exemptions with the need to standardize a rapidly growing industry.
Experts and critics across the board dispute the concerns listed above. Indeed fracking is also has the potential to bring about major benefits to both local and national communities. In short, fracking is a multifaceted affair. There is fracking in theory and fracking in practice – performance and impact may vary substantially from case to case. On one hand, it is an advanced natural gas extraction method. Fracking may be a tool for stimulating the economy and spurring job creation. On the other hand, the possible effects of this extraction technique embody a political dispute over its desirability as a strategy for energy independence.