Applications to carry out exploratory fracking have been recently been requested in the UK, only to receive a bad press among conservationists and protesters.
Fracking is big news in the USA but is less used in Europe due to opposition from anti-fracking lobbies. It is banned in France and Bulgaria, and only recently permitted in the UK.
But is it all bad or is it a necessary evil in a time where energy is scarce and we have to utilise all our energy sources?
Fracking
Fracking is the industrial technique of hydraulic fracturing. This drilling technique is used to recover gas from shale rock, and so can only be used in specific geological areas. Shale gas is a high carbon fuel, around 75% of its mass is carbon.
In order to recover gas from the shale rock energy companies have to drill down into the shale rock to create a well. An area is leveled and covered in caliche rock to make a drill base. A drilling rig is used to drill multiple wells into the shale rock. Even though the rigs are large (up to 45 meters high) it can take several months to dig a single well.
The wells are drilled both vertically and horizontally to create pathways to release gas. Horizontal drilling is more often used as it means fewer wells have to be dug. The location of the wells will depend on the geology of the rock in that specific area, and where the gas pockets are located within it. Wells regularly reach a depth of 2-3 kilometers with horizontal drilling for 1-2 km.
When the wells has been drilled a high pressure mixture of water, sand and chemicals are injected into the rock for several days. This allows the gas to flow out to the head of the well so it can be collected. Tanks are used to collect the fracking fluid and gas mixture, from which the gas is collected and pumped through pipes. The wells are then closed and sealed with cement to prevent leaks.
Disadvantages
Fracking is a very intrusive operation on site, and has a large environmental impact on the surface and ground below. On completion of the works there is some reinstatement to the landscape, although the scars of the process are still very evident.
The plant required is huge and noisy and significant infrastructure is required to bring in plant, vehicles and equipment to the site. This does impact significantly on people living in the area. In the US and Australia the local economy has suffered and house prices in surrounding areas have fallen.
Environmental concerns includes the huge amounts of water the process requires; four million galleons per borehole. This has to be transported to site at environmental cost and waste water has to be treated.
It is also feared that potentially carcinogenic chemicals may leach into the environment or contaminate groundwater, although there is a very low risk of this through the process there may be incidents around transport and storage. However, there may be more cause for concern about the long term integrity of the wells after they have been closed if they start to leak.
Fracking has been known to cause small earth tremors. In 2011 two small earthquakes hit the Blackpool area following fracking, and one in Lancashire. However, instances of this occurring are rare.
Fracking is still looking to release fossil fuels, which damage our environment. Money is invested in this technique rather than cleaner, renewable forms of energy.
Advantages
However, as natural resources are scarce and alternative energy is limited there is a argument to recover gas that was previously unobtainable through new techniques such as fracking.
It is estimated in USA and Canada that fracking will provide fuel for the next 100 years.
In the UK shale gas will significantly supplement the dwindling north seas gas reserves. Potentially trillions of cubic feet of shale gas could be recovered by fracking from northern England alone.
Renewable energy is not yet at a level to replace fossil fuels and so the use of shale gas will help to bridge this gap.
If shale gas is not used then energy costs will rise significantly as they become scarcer and this will be felt by many businesses and homes already hit hard by rising fuel bills.
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