Shale gas, hydraulic fracturing, natural gas extraction, onshore unconventional oil and gas, fracking…
If you follow the news at all, you’re sure to have come across these terms in abundance – but what are they talking about? Are they all different names for the same process? If so, what is that process? And why is it so controversial?
Fracking, in its many guises, is an industrial process used to access reserves of natural gas trapped in underground rock. It’s well established in America and credited by some as delivering a “boom” in the US’s energy economy, boosting domestic oil supplies and reducing gas prices. Potential for fracking in the United Kingdom has been identified – but development is yet to take off, with much debate surrounding the potential benefits and risks of the process.
Supporters endorse fracking as a transitional fuel that will boost our gas reserves as we move to more sustainable solutions. They argue that transitioning to entirely renewable energy technologies is a long process and that fracking provides a short-term solution to supplement our existing resources as we develop our green energy infrastructure.
Detractors, however, argue that the impact on climate change of continued fossil fuel combustion demands faster transition to green fuels and that burning gas extracted by fracking will cause continued irreversible damage to the planet. They also argue that the local environmental and social risks associated with fracking outweigh potential benefits.
So what is fracking?
Hydraulic fracturing, or natural gas extraction, is the process of drilling underground to release and capture reserves of gas or oil. It’s a process widely used in the North Sea, the main source of UK “home-grown” supplies of gas and oil.
Fracking, however, is popularly used to refer to onshore gas extraction. The process for the extraction of these onshore reserves – referred to as shale gas or unconventional oil and gas – is similar but with major differences that make a significant contribution to the viability and environmental impact of attempts to extract onshore oil.Hydraulic fracturing, or natural gas extraction, is the process of drilling underground to release and capture reserves of gas or oil. It’s a process widely used in the North Sea, the main source of UK “home-grown” supplies of gas and oil.
A fracking well is first drilled down vertically. The vertical well goes beneath the water table and reaches depths of over a mile. The well is then extended horizontally. Perforations are made in the horizontal pipe wall through which a high pressure water mix is sprayed. This causes fractures in the shale rock which release the gas inside. The name fracking comes from this fracturing of the rock.
The water mix contains sand and chemicals. The sand helps the fissure stay open, whilst the chemicals are used for a number of purposes including reducing friction and preventing pipe corrosion.
What are the benefits?
There are potentially trillions of cubic feet of shale gas in Britain. This represents scope to significantly boost our home supplies of gas. Whilst burning shale gas is still damaging for the environment, it releases only half as many harmful emissions as coal. It’s often billed as a cleaner alternative to coal.
What are the disadvantages?
Campaigners against fracking argue that burning natural shale gas will continue to contribute to climate change. They argue that fracking will mean continued pollution, continued reliance on non-renewable resources and delayed development of green technology.
Opponents to fracking are concerned that the process itself is not environmentally friendly. Millions of gallons of water are required for every fracking well. This quantity of water runs risks for water shortages and also puts approximately 400 water tankers on the road per well. The volume of chemicals required is estimated at 40,000 gallons per fracturing.
There are also a large number of environmental risks associated with fracking.
Concerns that chemicals may escape into groundwater have been fuelled by 1000 documented cases of water contamination in areas of America which have been fracked. Fracking companies are not obliged to make public the full chemical composition of their water mix, however known chemicals include toxic elements and carcinogens. Fracking companies have been known to use lead, uranium, mercury, ethylene glycol, radium, methanol, hydrochloric acid and formaldehyde.
It is debated whether cases of contamination have resulted from bad practice or from inherent risks in the fracking process.
There have also been reports of small earthquakes in areas surrounding fracking sites, although fracking supporters maintain that these are less significant than tremors associated with coal mining.
The impact on the UK countryside and rural landscape is also cause of concern for some. Tens of thousands of fracking wells would be required to extract gas in quantities to match the current energy output of North Sea Oil.
What’s the future of fracking in the UK?
As of this week, the government have pledged to develop UK fracking projects despite public opposition continues to rise. Careful regulation, high safety standards and research into potential risks have all been proposed to minimise environmental impact.
It’s unclear at present what the practical upshot of these deliberations will be.
Let’s hope whatever decision is made, it is truly for the benefit of all and not for the profits of big businessmen. In this century, choices in the energy industry have ramifications far beyond the national economy. Each of us wants to be able to provide comfort for our homes without damaging the environment, and this can only be possible if governments and energy companies across the world truly work together for an environmentally and economically viable solution.
We hope that it won’t be long before processes such as fracking will become unthinkable as we develop and expand our green energy network for truly sustainable living.