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Fracking hell or gas delight?

There has been much opposition to shale gas extraction via the new techniques of directional drilling, hydraulic fracturing and pressurised gas collection/release, with dramatic footage of water from domestic taps catching light due to dissolved gas in areas of the US where shale gas ‘fracking’ projects are underway. It certainly makes for powerful videos. See: www.youtube.com/watch?v=dZe1AeH0Qz8 and www.youtube.com/watch?v=dEB_Wwe-uBM

However, some say this is not new and happened long before shale gas extraction started. Maybe so, but there are other eco issues, including ground water contamination with chemicals that are forced deep underground, along with water and sand, to fracture the shale and release its gas. www.bbc.co.uk/news/science-environment-13333473

In addition there’s the shear volume of water need for fracking. Moreover shale gas is still a fossil fuel, so burning it produces CO2- and any leakage from fractured strata could be serious for the climate, since CH4 is a much more powerful greenhouse gas.

The Tyndall Centre has called on the UK government to put a moratorium on shale gas operations in the UK until the environmental implications are fully understood. It was also worried that a rush to exploit shale gas could divert effort away from developing a long-term sustainable low carbon economy. www.tyndall.ac.uk/sites/default/files/coopshalegas_ reportfinal200111.pdf

Similarly, in a RIIA report ‘The Shale Gas Revolution: hype or reality?’ Paul Stevens, senior research fellow at Chatham House, commented ‘in a world where there is the serious possibility of cheap, relatively clean gas, who will commit large sums of money to expensive pieces of equipment to lower carbon emissions?’

Global shale gas reserves are put at 456 trillion cubic meters compared with 187 trillion cu.m for conventional gas, according to a 2010 World Energy Council report. Over 60% of shale gas deposits are in North America and Russia. Stevens says producing shale gas using horizontal ‘fracking’ costs $3 or less per million British thermal units whereas it’s said that conventional gas drilling cost about $10 per million Btu.

So what hope is there for renewables- until shale gas runs out? But there are some uncertainties about whether the shale gas revolution will be as big as some predict, and Stevens says ‘if it fails to deliver on current expectations- and we will not be sure of this for some time- then in ten years or so gas supplies will face serious constraints’. www.chathamhouse.org.uk/files/17317r0910stevens.pdf

Certainly some say the energy costs of extraction may make it counterproductive as the reserves thin out. So there could be a boom and bust scenario.

And the eco costs may be large. A leading critic is Professor Robert Howarth from Cornell University. In a draft paper last year he claimed that hydraulic fracturing may contribute significantly to greenhouse gas (GHG) emissions. He said that there were significant GHG emissions from the well-drilling, water-trucking, pipeline-laying, and associated forest- felling. Combining the effects of combustion, production, distribution, and leaked methane gives the fuel about the same GHG emissions as coal- 33 grams of CO2, compared to 31.9 grams for coal.

The analysis was partly based on a methane leakage estimate of 1.5% of natural gas consumed, a figure assumed by the federal government, methane of course having much more climate impact per gram than CO2. Although he admitted that it was only a preliminary assessment,. it drew fire from the America’s Natural Gas Alliance, who dismissed his assertions as ‘preliminary and speculative and not backed by hard data’. It added ‘Natural gas is twice as clean as coal and is available here in America in significant abundance today. Alongside the development of renewables, natural gas has a key role to play in transitioning our nation to a low-carbon economy.’

Howarth attracted similar criticisms when earlier this year, more of his results were widely quoted: in a new paper he claimed that generating electricity from shale gas produces at least as much climate impact as coal-fired power, and perhaps more. www.eeb.cornell.edu/howarth/Howarth%20et%20al%20%202011.pdf

To make sensible comparisons you have to take account of the fact that methane’s residence time in the atmosphere is much less than that for CO2, but Howarth did offer data for both 20 years and 100 years. ‘Compared to coal, the footprint of shale gas is at least 20% greater and perhaps more than twice as great on the 20-year horizon, and is comparable over 100 years’.

Howarth has articulated what seems to be a common US view: ‘My strong belief is that shale gas has been promoted far beyond the objective evidence of what it can and cannot do. It is time to step back, and objectively analyse whether this is a reasonable energy technology for our future. It is also time to analyse how environmental issues associated with the technology might be reduced, and at what cost.’

Some US cities including New York and Pittsburg are trying to halt local drilling for shale gas, with Philadelphia calling for at least a temporary ban on new wells in the watershed that serves the city. There have also been concerns in Texas. See: www.chron.com/disp/story.mpl/editorial/7412406.html

Fracking in the EU

So far it’s mainly been a N. American issue. But successes in the USA have led to prospecting across Europe. A report by IHS CERA said that unconventional gas reserves, including shale gas, in Europe could total 173 trillion cubic metres. Interestingly, France imposed an interim moratorium on shale gas extraction earlier this year, and may ban it entirely, after the government backed a draft bill that would outlaw the controversial process.

It’s estimated that the UK could meet around 10% of its current gas needs from shale gas, if it can be extracted at a commercial rate. And with exploratory drilling starting last year in Lancashire, the Energy and Climate Change Select Committee has been looking into its implications for the UK. The results should emerge soon, but in its evidence to the Select Committee, Scottish and Southern Electricity plc said that, while shale gas was a viable if relatively small option for the UK (compared to the US), ‘there is a concern that with limited capital for investment in the energy industry, significant development of policy incentives to encourage development of shale gas resources in the UK, alongside uncontrolled growth in gas-fired generation could decrease investor certainty on UK policy direction towards renewables, CCS and/ or nuclear. Although this would lead to a short-term gain in carbon emission reductions, it would be to the detriment of the long-term decarbonisation of the UK power sector’.

All the submissions are at: www.publications.parliament.uk/pa/cm201011/cmselect/cmenergy/writev/shale/contents.htm

Most environmental groups have clearly made up their minds. Jenny Banks, climate and energy policy officer at WWF-UK, called on the British government to halt shale gas exploration. ‘It would be ridiculous to encourage shale gas when in reality its greenhouse gas footprint could be as bad as or worse than coal. We need to reject this source of gas, and have a clear plan to move away from our dependency on fossil fuels and harness the full potential of renewable technologies.’

Friends of the Earth offered a quite nuanced view to the Energy and Climate Select Committe: ‘available data suggests that the carbon footprint of shale gas is smaller than that of coal used in electricity production, although it is higher than that of conventional gas. Therefore if shale gas was to displace existing coal electricity generation then there would be a net carbon reduction. However, as some coal is being displaced anyway via the LCPD, new shale gas would more than likely be displacing other types of electricity generation such as renewables’.

However there are other views. For example, a new report from the Global Warming Policy Foundation, which is headed by Lord (Nigel) Lawson, argues that the eco-hazards ‘are much smaller than in competing industries’. It claims that ‘a single shale gas well uses in total about the same amount of water as a golf course uses in three weeks’. Perhaps not the best comparison! It concludes ‘A surge in gas production and use may prove to be both the cheapest and most effective way to hasten the decarbonisation of the world economy, given the cost and land requirements of most renewables’.
www.thegwpf.org

The debate continues.

For a good review of EU shale gas developments, see: http://e360.yale.edu/feature/frackingcomestoeuropesparkingrisingcontroversy/2374/

Posted by Dave Elliott on May 21, 2011 11:30 AM | Permalink