Viewpoints: Fracking's risks and benefits
The UK government recently lifted its moratorium on the controversial process known as hydraulic fracturing, or fracking. The technique involves pumping fluids into a well to recover natural gas from shale rock.
However, fracking has been linked to some minor earthquakes, and there are concerns about its possible environmental impact. So what benefits could hydraulic fracturing bring, and how concerned should we be?
Prof Richard Davies, Durham Energy Institute
During the recent debate on fracking technology in the UK, we may have been distracted from considering some of the real issues in developing our shale gas reserves.
The much-popularised link between fracking and contamination of water supplies remains unproven and our research at Durham University shows the chances of it ever happening can be dramatically reduced if the fracking is carried out at vertical distances greater than 600m below the drinking water aquifer.
We also find that fracking has only caused three reported examples of felt earthquakes (one of which was in Lancashire), but there have been hundreds of thousands of fracking operations.
A real issue is that for the UK to produce enough gas for it to make a difference to our indigenous supplies requires a lot of wells - many more than are typical for conventional gas reservoirs.
Therefore the long-term integrity of boreholes and the cement used to seal the boreholes and prevent leaks will be of critical importance.
The risks appear to be tiny - of thousands of shale gas wells drilled in the USA, only a handful have reported problems with leakage and all were successfully sealed by subsequent work. But one leaking well is one too many.
The UK does not have an abundance of rigs and fracking equipment, so a rapid growth in shale gas production is unlikely.
If the social acceptance is there so that enough wells can be drilled, then the long-term integrity of the boreholes is a real issue that will need to be a priority for shale gas companies and regulators.
Mónica Cristina, spokesperson, Shale Gas Europe
Shale Gas Europe welcomes the UK Government's decision to lift its temporary ban on exploratory hydraulic fracturing for shale gas in the UK.
The lifting of the ban now allows the UK to explore the potential of securing its energy supply, to stimulate jobs and the economy alongside reducing CO2 emissions when replacing higher-carbon-content fuels.
In addition to this, [Energy Secretary] Ed Davey has made the case that shale gas could prove particularly valuable in replacing the UK's dwindling North Sea supplies.
The potential opportunity is substantial. As the British Geological Survey estimates, UK shale gas resources may be 50% larger than conventional gas resources. With exploratory drilling now going ahead, estimates will be more accurate and the British Geological Survey is due to release a more comprehensive estimate of the UK's shale gas resources in 2013.
The UK Government's approach is also environmentally responsible. The UK has conducted a thorough review of hydraulic fracturing and there is substantial scientific evidence to support the UK Government's decision. In June 2012, the Royal Society and the Royal Academy of Engineering concluded that the health, safety and environmental risks associated with the technique can be effectively managed.
The government decision to move forward with the safe and sustainable development of its domestic natural gas resources is an economic opportunity which should be embraced.
Helen Rimmer, Friends of the Earth
The Government's decision to give fracking the green light will send shock waves through communities across the country.
And they are right to be alarmed. Fracking is banned in France and Bulgaria, with moratoriums in place in large parts of Europe. A recent EU report warned that fracking poses high risks of water contamination and air pollution - and there have been instances of both in the United States.
Fracking also uses huge quantities of water - around four million gallons for each [borehole]. This could have major repercussions for precious supplies. The south-east of England, an area the fracking industry is particularly interested in, already has water supply problems and was in drought earlier this year.
The local economy could also be hit. Experience from the US and Australia shows key sectors such as agriculture and tourism have suffered and that local house prices could fall. Furthermore, the jobs benefits are frequently over-stated.
Then there is the crucial climate impact. The Government's official climate advisors warn that the nation's power sector must be largely decarbonised by 2030 if the UK is to meet its climate targets. Fracking is part of the Government's reckless dash for gas that would leave the UK hooked on dirty gas for decades.
The cheap fuel argument is simply a mirage. Earlier this week Government advisors said shale gas wasn't a "game-changer" as it could only meet a relatively small share of gas demand.
The reality is we do not need to gamble on fracking. Investing in clean British energy from the wind, waves and Sun - along with a major energy-saving drive - would create hundreds of thousands of new jobs, boost energy security and keep the lights on.
It is time to take our foot off the gas and develop a cleaner, safer energy system we can all afford.
Kevin Anderson, Tyndall Centre for Climate Change Research
Shale gas is the same as natural gas - it is a high-carbon fuel, with around 75% of its mass made of carbon. For the UK and other wealthy nations, shale gas cannot be a transition fuel to a low-carbon future. Anyone who says differently does not understand our explicit international commitments under the Copenhagen Accord, the Cancun Agreements - or, alternatively, is bad at maths.
The UK's commitment to make our fair contribution to reduce emissions in line with keeping global warming below a 2C rise gives a very clear global carbon budget, and hence a UK budget: in other words, how much carbon we can put into the atmosphere over this century. Here the maths is unambiguous - we have insufficient budget for the carbon we are already emitting and by the time shale gas is produced in any quantity (five to 10 years), there will be no emissions space left for it. The maths is that simple, even if the conclusion is not what we want to hear.
Another fundamental mistake made by many experts on shale gas is that they assume it is lower-carbon than coal, but this is valid only if we don't burn the coal. In a world that is hungry for energy, any UK shale gas used here will mean we import less gas and coal - gas and coal that will simply be burnt elsewhere.
The climate does not care from which country the carbon comes from - so burn shale gas here and UK emissions may go down but global emissions will go up. Shale gas is another high-carbon fossil fuel - it just adds to the problem - in the absence of a stringent limit on total carbon emissions it will not substitute for coal.
Finally, even if the technology of "carbon capture and storage" can be made to work with gas - the level of emissions reductions will not be enough to meet our international carbon commitments. In the UK and globally, we are now reaping the reward of a decade of hypocrisy and self-delusion on climate change. We pretend we are doing something ourselves, whilst blaming others for rising emissions.
The truth is out - it is a tragedy of the commons par excellence - we are all to blame and we have left it too late for a technical fix. We are heading towards a global temperature rise of 4C to 6C this century; if we want to get off this trajectory, shale gas needs to stay in the ground and we, in the wealthy world, need to consume much less energy - now.