The countryside around Weeton,a few miles inland fromBlackpool in the northwest ofEngland, seems pretty unremarkable.But what lies beneath it could proverevolutionary, transforming Britain’senergy supplies and also our fuelbills. Around 3000 metres beneaththis farmland lies a huge band of rockknown as the Bowland Shale, andtrapped inside it are vast quantities ofnatural gas. Now, a small British energycompany is drilling down into the rockto explore its potential. And alreadythere’s talk of this ‘shale gas’ providingas much as 10 per cent of the nation’sgas needs within a decade.
Gas accounts for 40 per cent ofthe energy used in the UK and withrocketing energy prices making theheadlines, the discovery of a huge newsource of it must be good news. Moreso across the Atlantic, where a reportpublished by the US Energy InformationAdministration declared that by 2035shale gas would account for nearly halfof the country’s gas production. Thereport also said that extraction of shalegas around the world would increaseglobal gas resources by up to 40 percent. Both were conservative estimatesthat don’t take into account regions andcountries – including Russia – that are yetto be inspected.
But not everyone is convinced byshale gas. Climate change experts warnthat shale gas is still just a fossil fuel,and thus a source of carbon dioxide– the prime driver of global warming.Environmentalists have also raisedconcerns about the impact of extractingthe gas. They point to incidents ofdrinking water allegedly becomingcontaminated with the chemicals usedto extract the gas, and even shale gasitself, leading to tap water becomingflammable. Such fears have alreadyprompted the French government toimpose a temporary ban on shale gasextraction. Meanwhile in the UK, aminor earthquake at the site in Weetonled to test drilling being suspended atthe end of May 2011.
A new way to get an old fuel
So should we welcome the discovery ofthis new energy source, which couldprove to be the biggest source of naturalenergy in the UK since North Sea Oil? Orshould we fear it as a potentially lethaleco-nightmare?
According to Dr Richard Selley,emeritus professor of petroleum geologyat Imperial College, London, there’sa host of misconceptions about shalegas. And one of the biggest is that it’sa new source of energy. Shale gas hasbeen used by householders in partsof the US for centuries. “Productionhas long carried on throughout theAppalachians as a cottage industry, butprofit margins were too small to interestmajor companies,” he says. Shale gaswas first found in the UK in 1875, butagain no-one gave much thought to itscommercial value.
Similar indifference prevailed asrecently as the 1980s, even as expertswarned of an impending energy crisis.At the time, Dr Selley tried to drawattention to the opportunities: “Attemptsto inform the wider world of the UK’spotential shale gas resource failedmiserably,” he recalls.
But all that has changed. Part of thereason has been technological advancesin extracting gas. “It’s now possible todrill vertically and horizontally, steeringthe drill-bit to stay in one bed of shale,”says Dr Selley. Such advances are at theheart of another misconception aboutshale gas. Any mention of drilling rigsand wells conjures up images of hugederricks towering into the sky. “Peopleneed to put aside the conventional ideaof what extraction involves,” says DrSelley. “Advances in drilling technologymean you can now have 20 to 30 wellscoming off one small rig.”
Certainly one of the most strikingthings about the test site near Blackpoolis the modest size of the plant. The rigis about the size of a water tower, andsurrounded by pumping equipment anda small group of buildings. Accordingto Cuadrilla, the company that runs thesite, even that is only temporary, as therig is only needed to start the release ofthe gas. The process is called hydraulicfracturing, or ‘fracking’, and involvespumping a mixture of pressurised water and chemicals into the well, creatingtiny fissures in the shale that allowthe gas within it to percolate out.
After a few months, the fracking iscomplete and the gas starts flowingup the well. The engineers can thenmove on, leaving a small collection sitebehind. “A site of 10 to 12 wells wouldcover about a hectare,” says Cuadrilla’sCEO Mark Miller, “and if you planted ahedge, you wouldn’t see them”.
But environmentalists insist thatfracking can have consequences that areanything but short-term. Aside from thesuspension of activity at the Weeton site,bans on fracking have been imposed in parts of the US and Europe, andthe Green Party has called for a ban onfracking in the UK.
Critics of the process have focusedon incidents highlighted in Gasland,an award-winning documentaryreleased in the US in 2010. The filminterviews residents who blame chronicill-health on the chemicals used infracking, and claim to have beenoffered compensation by some energycompanies. In one dramatic sequence,a householder succeeds in igniting thewater emerging from a tap, becauseof the amount of natural gas that hasseeped into the supply.
Industry experts insist that theincidents are due to contamination bymethane from much shallower sourcesof natural gas than those now beingexploited. At the Weeton site, Cuadrillapoints out that the shale being drilledis thousands of metres deeper than theaquifers supplying local water, withsolid rock between the two.
Even so, Miller doesn’t dismiss theconcerns out of hand. “It’s about doingthe job right,” he says. “There havebeen cases in the US, but they’re rare –40,000 new wells are drilled each year,around 8 to 10 go wrong and someonegets gas in the water table. But it’savoidable if you adopt best industrypractice, and it’s easily repairable.”
Energy crisis vs climate crisis
Not all environmentalists are opposedto the idea of using shale gas, in anycase. Earlier this year, the US-basedWorldwatch Institute announced thatwhile industry must work harder totackle the environmental risks, shalegas could help nations move towards alow-carbon economy. The same pointwas highlighted in a recent report by theindependent UK-based Global WarmingPolicy Foundation. It argued thatnatural gas is the most efficient fuel forgenerating electricity, and produces lessthan half the carbon dioxide producedby burning coal.
Yet according to Professor KevinAnderson of the University ofManchester’s Tyndall Centre for ClimateChange, there’s a huge flaw with thisargument for shale gas. “I find worryingthe naivety in the assumption thatwe’ll all use shale gas instead of coal,”he says. In a report commissioned byThe Co-operative, Prof Anderson andhis colleagues warn that the world’sdemand for cheap energy is likely tolead to shale gas being used as well as,rather than instead of, other sources.“All the climate cares about is the totalamount of carbon being released, notthe relative amounts from differentsources,” explains Prof Anderson.
Such arguments may have lesspotency now that public concern aboutglobal warming trails more immediatefears about soaring gas prices. At thesame time, politicians are increasinglyfocusing on energy security – there have been predictions that by the end of the decade80 per cent of UK gas will come fromforeign sources.
In the face of such problems, thecase for exploiting shale gas can seemcompelling. Prof Anderson agrees.“It will help in the short term,” he says.“But if it affects climate change andissues like food supplies, that couldprove to be far too narrow a view ofenergy security.”
Note: since this article was first published in Summer 2011, a government-named panel of experts has given the green light for shale gas extraction near Blackpool, as long as the fracking companies follow procedures outlined in the panel's report.
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