Energy companies in the 21st century are able to use a variety of techniques to extract oil, natural gas and other fossil fuel sources. New techniques may allow more efficient extraction of fuel, resulting in lower prices for consumers. Many energy providers like Cunningham Energy invest in new processes and technologies to bring cleaner and more efficient energy solutions to consumers.
Traditional oil extraction begins with a well, which is simply a hole bored through the earth to the oil reservoir by the familiar drilling rigs. Once the well has been dug, a series of valves known as a “Christmas tree” is placed near the exterior. The Christmas tree can be fitted to pumps and pipes to connect the well to a pipeline network and deliver the oil.
When a well is new, its internal pressure is enough to push the oil to the surface. Eventually, the well can no longer generate such pressure and enters the secondary extraction stage. During this stage, external pressure sources must be used to push oil to the surface. The most common secondary extraction method is water injection, which is just what it sounds like: water is injected into the well to increase pressure and push more oil to the surface.
After the well reaches the point where secondary extraction methods can no longer efficiently deliver oil, the well may be retired or tertiary extraction methods may be used. Tertiary extraction involves heating or chemically treating the oil in the reservoir to increase its viscosity and allow it to flow more freely. When used, these techniques can allow extraction of an additional 5-15% of the reservoir. After tertiary extraction techniques no longer efficiently deliver oil, the well will be retired.
When an oil reservoir is situated in very dense or tight rock formations such as sandstone or shale, traditional drilling may not be effective. Hydraulic fracturing (or fracking) is a technique that may be used in such cases. Fracking involves using highly pressurized liquids to split the rocks in order to access the oil reservoir. This method has become very common in North Dakota’s recent oil boom. Much of North Dakota sits on a rock unit known as the Bakken formation, which is rich in shale oil. The boom has led to tremendous economic growth in North Dakota.
The use of hydraulic fracturing and advanced tertiary extraction techniques allow access to oil today that would not have been accessible in the past. This results in more jobs and greater energy access for consumers.