Analysis The government has given the go-ahead for further exploration of the UK's shale gas reserves. Independent surveys suggest these reserves may yield more energy for the nation than North Sea oil.
The shale gas will be collected using induced hydraulic fracturing, known as "fracking", which splits rocks thousands of feet below ground using high-pressure liquid.
This is a defeat for environmentalist activists and the powerful renewables lobby - but they have a valuable consolation prize few have noticed. Under the proposed regulatory regime, during the fracking process any tremors that measure 0.5 or higher on the Richter scale may trigger an automatic halt to operations under a "traffic light" scheme outlined by the Lib Dem energy minister Ed Davey.
What does this mean? Well, tremors below magnitude 3.0 are considered to be barely noticeable, and bear in mind that the Richter scale is logarithmic: the energy released by a tremor of magnitude 0.5 is equivalent to the energy released by a large hand grenade.
But don't forget this is happening thousands of feet below the surface: a 0.5 event escapes the detection of all but the most sensitive seismic monitoring equipment.
Yet one 0.5 event alone will be enough to halt fracking and it can only be restarted by the minister. Which, in practice, means it's in the hand of the fanatically pro-wind Whitehall bureaucrats at the Department of Energy and Climate Change.
By contrast, the UK consortium Cuadrilla - which halted exploratory fracking near Blackpool in early 2011 after causing two minor earthquakes - uses the German safety standard, one of the world's more conservative standards. This sets the maximum permissible tremor magnitude at 2.6 and recommends mitigation measures if seismic activity exceeds magnitude 1.7 - after which the drillers halt water injection and reduce the pressure on the shale.
Davey admitted that the 0.5 red-light threshold is "far below a perceptible surface event, but larger than the expected level generated by the fracturing of the rock", which he considers "an appropriately precautionary approach". But he admitted: "We received representations in our consultation that this is too cautious."
Environmentalists fear that deep drilling may disturb Silurians,
the race living under the Earth's crust in Dr Who
The combination of fracking and horizontal drilling techniques can be used to unlocked new reserves of exploitable gas. (The combination is also deployed to unlock renewable geothermal energy.) The consequences for the energy market have been dramatic. US gas prices have fallen by two thirds, the country is now self-sufficient on gas - and the United States enjoyed the largest fall in CO2 emissions of any major country as its power generators switched from coal to gas.
Reports suggest that the UK sits on one of the richest deposits of shale gas in the world. An unpublished but independent estimate of UK gas potential by the British Geological Survey suggests it may be more significant to the UK economy than North Sea oil. Cuadrilla initially estimated the UK has enough gas to make it self-sufficient for 15 years at current consumption rates - but this may be underestimated by a factor of four.
We just don't know - and today's announcement allows Cuadrilla to further explore the Bowland Shale in Lancashire.
Shale exploitation and the cheap energy it produces - with lower-than-coal CO2 emissions - poses an existentialist threat to the renewables industry as the stark contrast in price and reliability are inescapable.
On Monday the Mayor of London Boris Johnson characterised objections to fracking as irrational and psychological, writing of the environmentalists:
Beware this new technology, they wail. Do not tamper with the corsets of Gaia! Don’t probe her loamy undergarments with so much as a finger — or else the goddess of the earth will erupt with seismic revenge. Dig out this shale gas, they warn, and our water will be poisoned and our children will be stunted and our cattle will be victims of terrible intestinal explosions.
This is not an original observation. It's one we've made it here before. There is a powerful symbolism in the Earth Goddess Gaia being penetrated. However, here at Vulture Central we fear the fate of any undiscovered subterranean reptile-human hybrids that fracking may disturb. (This is a joke. We are merely extending the environmental lobby's favourite rhetorical weapon - the precautionary principle - to its natural conclusion.)
Curiously, the "carbon capture and storage" systems, which grab CO2 from fossil-fuel power stations and bung it deep underground, are favoured by environmentalists, but they too require fracking. Activists thus find themselves in the peculiar position of praying for earthquakes when shale gas is recovered from fracking, but not when CO2 gas is being buried using fracking.
Energy consultant Nick Grealy, an advocate of shale gas and whose predictions have proved accurate, had some thoughtful advice for the environmental lobby in this piece.
"UK Greens have to start thinking more about climate change and less about the Committee for Climate Change," he wrote.
Taking his point one step further, environmental activists ought to think more about ways to reduce CO2 rather than setting targets for power generation from wind, solar and other renewable energy sources. As Voltaire wrote: le mieux est l'ennemi du bien - the best is the enemy of good.
In reality, the renewables target strategy died in George Osborne's autumn mini-budget statement last week. The chancellor said he is looking forward to shale gas production in 2015, and 30 new gas-fired stations.
The installation of a hand-grenade-triggered "red light" is very much a rearguard action. It is very hard to imagine the Ofgem-predicted power cuts rolling across Britain while shale gas extraction machines lie idle, halted by a safety "traffic light".
One rather fears for the safety of the hippies should that ever happen. ®