Fossil fuels are the major cause of massive Carbon Dioxide emissions. It is also one of the major reasons why our air becomes polluted leading to various respiratory symptoms such as shortness of breath, wheezing, and asthma. Sometimes the air we breathe may be so heavily polluted that it may lead to premature death. Although fossil fuels heavily release carbon dioxide and cause massive amount of air pollution, not all of the fossil fuels pollute the environment or damage the health in the same way. This can be said of natural gas; a type of fossil fuel which produces clean and efficient energy however with reduced air pollution and limited health implications than the other fossil fuels.
What is Natural Gas?
Natural Gas is primarily Methane (CH₄), a hydrocarbon made up of one molecule of carbon and four molecules of hydrogen. Natural gas is a fossil fuel similar to coal and oil, and was formed from dead plants and microorganisms which sunk to the bottom of the oceans and swamps and started to gradually decompose. Subjected to heat and pressure these organisms were converted to gas which took millions of years to occur.
Natural gas is trapped underground inside a rock known as “Cap Rock” and stays underground until the natural gas is extracted. Natural gas can be categorized into dry and wet natural gas. Dry natural gas only consists of methane where as in addition to methane wet natural gas also contains ethane, butane and propane which can be separated by the manufacture to produce various products.
Natural gas as an energy source
Although natural gas is a fossil fuel like the previously mentioned coal and oil, the advantage that it has over the other fossil fuels is the amount of useful energy it can produce. It is said that about 90% of useful energy can be produced and delivered to consumers. However, just like the other fossil fuels, it is also a non-renewable energy resource. It is estimated that current reserves of natural gas will last for up to 35 years.
Benefits of Natural Gas
Natural gas is considered a vital source of energy. Its production of low carbon and high energy conversion rate is what makes it shine out from the rest of the fossil fuels.
Natural gas is trapped in reservoirs underground in the form of either dry or wet natural gas as previously explained. The most advantageous thing is that it burns very smoothly leaving behind absolutely no ashes making it one of the cleanest fossil fuels. In terms of carbon dioxide emission it leads to the least air pollution. Natural gas emits 117 pounds per million BTU (British Thermal Units) carbon dioxide compared to oil (170 BTU) and coal (200 BTU).
As the world is gradually leaning towards renewable energy resources through various technological advancements and scientific research studies, we can utilize natural gas as a source of energy in the meantime. This is because of its reduced impact on the climate and pollution. It also contributes significantly less to the greenhouse effect than other fossil fuels due to its previously mentioned low carbon dioxide emission.
Natural gas has the ability to be liquefied. This not only reduces the storage capacity of the substance but also leads to cleaner and more efficient energy generation.
The general issue with fossil fuels is their extraction; similarly, it is very difficult to extract natural gas as well. Natural gas is trapped underground hundreds of meters below the earth surfaces and requires drilling to be extracted. Even after drilling, the natural gas is not found openly. It is rather trapped in cap rocks which can be found for long lengths underground.
Hence, to extract natural gas, “Fracking “, also known as “ Hydraulic Fracturing “ is carried out. In this process the first step is to find a site which has a vast reserve of natural gas. The site can be anywhere as long as it consists of a vast amount of natural gas. Then a long vertical hole known as a “wellbore “,is built deep underground passing multiple layers of sediment. It reaches its so called ‘kick off point’ where the process of horizontal drilling can commence at about 2000-3000 meters. The horizontal drilling can occur up to 1.5 Km on the black layer known as “shale rock layer” after which a perforated gun is introduced which makes small inch long holes at specific intervals perforating the well and into the rock layer.
After the drilling, fracking may commence. Fluid is introduced into the drilled hole at a high pressure sufficient enough to break down the shale rock. As the rock is broken down natural gases trapped in it may escape and dissolve in the fluid eventually being extracted by the extractors.
Fracking is constantly being used for the extraction of natural gas but it has its disadvantages as well. Fracturing requires good water supply, the disposal of the fracking water needs to be done carefully as it is a potential toxin and sometimes the fracking process may seep through to the water lines going to households and contaminate them. This fracking water can be detrimental to plants or crops if it finds its way to the water table. Earthquakes and potential seismic activities may also occur due to fracking.
Natural gas seems to have a lot of advantages for us but we need to be aware that like most fossil fuels and other non-renewable energy resources, it is only available to us in a finite amount. Along with the finite amount of natural gas, we need to be cautious of the potential damage its extraction can cause. Thus, we need to start finding alternatives to natural gas so that we may not encounter a position in which we are dependent on solely one finite resource to provide and meet our energy requirements. Our scientists work day and night to make sure we are able to comfortably shift to renewable sources of energy in future.