Q+A: is fracking the answer to our energy needs?

Following two small earthquakes in 2011, a government-commissioned report has concluded that hydraulic fracturing, or fracking, should be allowed to continue at the Preese Hall well near Blackpool.

The process involves injecting high-pressure water and chemicals into shale rock to release trapped natural gas (methane).

The company searching for gas, Cuadrilla, has accepted recommendations that drilling is carefully monitored by seismic sensors and that future earth tremors lead to a temporary shutdown.

In 2011, low-magnitude earthquakes led to the company halting operations at the site, although no damage was caused.

Tuesday’s report, commissioned by the Department of Energy and Climate Change, concluded that fracking had caused these tremors, which Cuadrilla accepts.

Are more small earthquakes likely?

The authors of the report say more earthquakes are possible. These are expected to be small, no higher than magnitude three, and are unlikely to cause structural damage.

But the authors say: “Such an event would be strongly felt by people within a few kilometres from the epicentre and could cause some alarm.”

As such, they want operations to be halted if tremors exceed a magnitude of 0.5, which Cuadrilla is happy to comply with. There will now be a six-month consultation period before a final decision is taken on whether drilling can resume.

Are there any other concerns?

Friends of the Earth is opposed to fracking on environmental grounds. Executive director Andy Atkins said: “Earth tremors aren’t the only risks associated with fracking – it’s also been linked to air and water pollution and produces gas that causes climate change.

“We should be developing the huge potential of clean British energy from the sun, wind and waves, not more dirty and dangerous fossil fuels.”

In the US, where shale gas has been extensively exploited over the past decade, television viewers have been confronted by disturbing images.

The 2010 documentary Gasland, shown by HBO, alleged that drilling had contaminated water, with domestic supplies affected by so much methane that householders could set fire to their tap water.

But defenders of fracking say that while there have been problems, these can be resolved by more professional drilling and better regulation.

Another criticism is that unlike renewable energy sources, shale gas is a fossil fuel that emits carbon and contributes to global warming.

What are the benefits of shale gas?

The US has made the most of its shale gas, which accounts for about a quarter of its natural gas reserves.

Shale gas has helped ensure that almost 90 per cent of natural gas used in the US is produced domestically, which means it does not need to rely on foreign producers for its supply.

The expectation is that by 2035, shale gas will make up 46 per cent of US natural gas production. Shale gas currently represents around 45 per cent of US domestic supply.

According to the US Energy Information Administration (EIA): “The availability of large quantities of shale gas should enable the United States to consume a predominantly domestic supply of gas for many years and produce more natural gas than it consumes.”

More shale gas has meant lower prices. Wholesale gas prices in the US are about 50 per cent lower than in Europe, and so are prices in the domestic market.

While natural gas adds to CO2, when it is used to generate electricity, carbon emissions are at half the level of coal and oil.
What about other countries?

Outside the US, China, Argentina, Mexico, South Africa, Australia and Canada have the biggest quantities of “recoverable” shale gas, according to the EIA. China tops the list, with 1,275 trillion cubic feet (tcf) of gas.

In Europe, Poland and France have the largest reserves. But while Poland is keen to exploit this future energy source, France has banned exploration.

What about Britain?

The EIA estimates that Britain has “recoverable” shale gas resources of just 20 tcf, compared with 180 tcf in France.

Britain produces just over two tcf of natural gas a year and consumes three, relying on imports to fill the gap. Cuadrilla estimates that the Bowland Basin site in Lancashire contains as much as 200 tcf of gas.

Only a small proportion of this can be extracted, but the company expects that within a few years, shale gas will contibute up to 10 per cent of Britain’s gas. The hope is that fracking will have the same effect as it has had in the US – lower gas prices.

Manouchehr Takin, a senior energy analyst at the London-based Centre for Global Energy Studies, told Channel 4 News: “It means more gas locally from UK sources. As to whether it will lower gas bills depends on volume.”