However the tack has at least changed slightly. The reason, says The Task Force On Shale, is that gas can provide a bridge to a low-carbon future. This is a something of a recurring meme these days from the fracking industry, and it has legs because it's a complicated argument to debunk. But debunked it needs to be.
First, what the Task Force got right. When burnt in a power station fracked gas gives off approximately half the carbon dioxide of coal. This is good, although not good enough to prevent dangerous climate change, which requires use to cut our carbon use by 90% or more. However The Task Force at least admits this and is only advocating shale as a bridge to cleaner and greener technologies.
Now here's the bad news, starting with the length of the bridge. Even if all the anti-fracking groups packed up and went home, and even if the British geology behaves and gives the frackers a clean run, shale gas will take time to develop. It is the fuel of the next decade, not this. New gas power stations will need to be built to burn it. They will have a lifetime of thirty years and there is no precedent for shutting down profitable stations early.
That means four more decades of carbon fuelled power in this country. This essentially 'business as usual' scenario, if followed worldwide, could, in a worst case scenario, see us committed to a global temperature rise of 4 degrees by 2050 according to the IPCC. This is a point that's easy to misunderstand - Emma Thompson recently came a bit of a cropper with it - so let's be clear: we won't see a temperature rise of 4 degrees by 2050, but we will have burnt enough fossil fuels to make such a catastrophic change in the climate inevitable by 2100, even if we don't burn another lump of coal or cylinder of gas in the second half of the century.
Indeed, some say that a 4 degrees rise could occur as early as the 2060s. This is scary as I might still be alive then, although two thirds of the world's plant and animal species probably won't be.
The Task Force would argue that a 'dash for gas' would avert a worst case scenario, but there's another factor they haven't considered. Whilst we might not be burning any more coal - in fact we definitely won't be burning any more coal if we don't build any more coal fired power stations, as the ones we have will be almost all retired by the end of the decade - but, in the absence of a global deal, there's no reason why other people won't burn our coal for us. That's what happened in America. Fracking reduced their domestic coal use, but coal mining actually increased. They just exported more.
So instead of replacing coal, fracking just adds another fossil fuel to the mix to be burnt alongside the black rocks. Dress it up any way you like, this is not good. The solution, as the divestment people will tell you, is to Leave It In The Ground. Fracking is only better than coal if the coal stays in the earth. At present there is no way the fracking industry, or its government supporters, can guarantee that.
The problems though don't stop there. Once of the biggest unknowns about fracking is the amount of the gas, methane, than leaks out, either during production or on the way to the power stations.
Methane is a far more potent greenhouse gas than carbon dioxide, and this is only partly offset by its
shorter life in the atmosphere. Overall the IPCC considers methane to be thirty times more potent than carbon dioxide, so the leakage rate is very important. Industry funded studies show very low rates, but independent studies have produced leakage rates of 12% or more. As a rate of just 3.6% would be enough to wipe any gains from the cleaner combustion of methane, these figures are worrying.
Incidentally, it's very easy to get yourself confused on this issue to. Methane is much heavier than carbon dioxide, so 3% of a certain amount of methane weighs a lot more than 3% of the equivalent amount of carbon dioxide. The House of Lords committee managed to confuse just about everyone by claiming Greenpeace had got this figure wrong, when it appears it that it was them who were confusing people.
Then there is the very real threat that fracking will up all the money the government has allocated to 'low carbon' energy, leaving solar, wind and energy conservation stranded.
All of this means that even if fracking was clean and safe, and even if there were hundreds of communities queueing up to welcome the rigs, its contribution to climate change would rule it out as a future energy source.
The Task Force would no doubt reply that I'm not being realistic, that the renewable alternatives just aren't there. But I would reply to them by asking: why aren't they there?
Is it because the government prefers to frack the Labour north rather than build wind farms in the Tory south, because it prefers to accept donations from the existing fossil fuel industry rather than pump prime the new solar revolution and because it prefers to risk catastrophe in the long term rather than spend money on prevention now?
It is a funny sort of 'realism' that ignores the physics of the problem in favour of the economics and the politics.
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