By Arvin Charles
Fracking and Shale Gas
Shale gas is a form of natural gas comprising predominately of methane, found trapped between layers of shale rock formations. Unlike conventional natural gas and oil which are found as reservoirs and pools underground which flow naturally or can be pumped to the surface using extraction wells, shale gas (often dubbed as unconventional natural gas) is much more difficult to harvest as it is almost impossible to remove the gas or oil from the hard shale – much like trying to squeeze out water from hard clay. However with the dawn of new technological advancements, namely hydraulic fracturing (fracking) and horizontal drilling, the development of shale gas has been on the rise, particularly in the US where only 1% of all natural gas production constituted of shale gas in the year 2000, but jumped drastically to approximately 20% in 2010, catapulting the US into the shale oil revolution.
Fracking differs from the drilling and extraction process of conventional fossil fuels mainly by the technique of injecting high pressure water into the wells, causing micro-fractures in the shale rocks. These fractures on the rock surfaces liberates the natural gas trapped within these porous shale formations which then flows into the well and out to the surface to be processed. Fracking is usually coupled with horizontal drilling whereby drilling is done all the way to the shale level underground and then turning the well horizontally along the shale level to maximize the fracking process, in turn increasing the extraction of natural gas within that oil field.
Advantages of shale gas
Natural gas is a primary feedstock in many chemical and electrical power generation processes and is far less polluting compared to other conventional fossil fuels especially coal. The combustion of coal releases not only carbon dioxide which contributes to the greenhouse effect and consequentially global warming, but also other toxic and harmful products like sulphur oxides (also a main contributor to acid rain). The burning of natural gas however, has a much lower emission of carbon dioxide, approximately 50% to 60% per unit energy to that of coal combustion. Hence, with the increased production and usage of shale gas compared to other fossil fuel sources, comes a significant reduction in air pollution and greenhouse gases. Though this may not put a halt to global warming, it may slow it down.
Another added advantage of using shale gas is that it may significantly reduce energy costs around the world. If the estimates are precise, North America alone has more than 1000 trillion cubic feet of recoverable shale gas depository scattered around. This is more than enough to supply the US with 50 years of natural gas and projections have shown that shale gas would make up half of the bulk of natural gas production by the year 2020. Hence, a massive production of shale gas would indeed cause a drop in natural gas prices, making heating and electrical energy costs more affordable for everyone.
The production of shale gas will also provide energy security and independency for many countries around the world. With the depletion of conventional fossil fuel resources and the uneven distribution of these resources around the world, many countries are handed the short end of the stick and would have no choice but to import fossil fuels, which in time also creates a lot of political tensions. However, with the introduction of fracking and horizontal drilling technology, many of these countries could join in the fossil fuel production game by tapping into shale depositories. Take for example India, the world’s fourth largest energy consumer. India has a strong energy dependency, importing almost 190 million tons of foreign oil in the year 2014. Thus, India is forced to spend much of its precious foreign capital on these imports as the high demand of fossil fuels outpace domestic production. The good news is that the country does not need to be this energy dependent following the discovery that they have a staggering 63 trillion cubic feet of shale gas reserves within the country on top of conventional natural gas reserves. The only hindrance for India to tap into this abundant resource lies in the fact that most of these depository basins are in remote and difficult-to-access areas, making infrastructure and logistics a challenge.
Disadvantages of shale gas
One of the greatest fears often associated to shale gas production is water contamination due to the fracking process. As pressurized water containing other additives and chemicals such as lubricating agents is pumped underground during hydraulic fracturing, most of this water is failed to be recovered for treatment and proper waste management. In many cases, this toxic water then seeps and leeches via various pathways into underground water sources causing bad contamination to drinking water sources nearby and also perhaps even destroying aquatic habitats and life. According to an article written by USA Today, 4 states confirmed water pollution during the epoch of the shale oil boom in 2014, triggering hundreds of complaints on well water pollution which created a public mistrust of shale gas production in the US. In addition, the harvesting of shale gas also brings about light and noise pollution especially in gas fields located near residential areas since the fracking process can be conducted all day and noise due to the vehicles moving through neighbourhoods, transporting barrels of shale gas.
Another growing concern about the mass production and transition towards shale gas is that the plight to develop renewables and cleaner energy technologies would become stagnant. Since the technology of fracking is so advanced and efficient in extracting shale gas from the shale formations miles underground, efforts to develop fuel for motor vehicles from biomass and even solar power would slow down as this would buy mankind a window of time to continue to use current fossil fuel vehicles before total depletion of natural gas and petroleum. The drop in natural gas prices due to the mass production of shale gas would also bring about further competition to renewable energy sources which are already having a tough time competing with coal.
A recent study published by the journal Science has also reached a conclusion that hydraulic fracturing can also trigger earthquakes. This very unobvious effect of fracking occurs due to the buildup of stress underground following the pumping of pressurized water in fracturing the shale formations. This can potentially trigger periodic earthquakes, which continue for months even after fracking is ceased. According to The Telegraph, a private company called Cuadrilla Resources admitted to have caused two seismic incidents in Blackpool in 2011 with magnitudes 2.3 and 1.5 on the Richter scale.
In short, it is beyond doubt that shale oil and gas is the new “black gold” of the century and many developing countries are already looking at exploiting this abundant resource with the depletion of conventional fossil fuels such as petroleum and coal. Although natural gas is a much cleaner alternative compared to coal, it still carries a relatively high carbon footprint and still has carbon dioxide emissions. Hence, a blind eye should not be turned in developing more clean and hopefully zero emission alternatives that are renewable and sustainable for generations to come.