We take it for granted that politicians are interested in power.

Not merely interested, in many cases, but obsessed. Gordon Brown, for example, became so crazed by power that he could have been mistaken for a member of the German hip-hop combo Snap!, advising us to "stay off my back, or I will attack, and you don't want that".

So it comes as a surprise to discover that the current batch of egomaniacs haven't, it turns out, been nearly interested enough in power. The energy regulator Ofgem has announced that the UK's reserve margin, currently 14 %, will fall to around 2% by 2015. What's more, within the next 10 years Britain will need to replace more than 20% of its generating capacity.

This presents the prospect of a return to the 1970s, a decade which those of us old enough to remember think of as suffused with the glow of candlelight – chiefly because there seemed to be power cuts every other day. According to Ofgem the risk of blackouts has doubled in less than a year, because of the Government's failure to replace coal and gas plants with new power stations.

The Coalition can point out that it is in the business of saving money, rather than spending it. Unfortunately it isn't even making a particularly good job of that. George Osborne's "ruthless" cuts, including a good number of projected savings which won't happen until 2018, amount to a reduction in public spending of 2.6% over eight years.

By contrast, when he was Chancellor, Denis Healey (no doubt working his sums out by the light of a hurricane lamp) managed to cut 3.9% in 1976-77.

Nor does it seem much of a saving for the Government to pay out thousands of pounds a time to commercial operations as compensation for turning off their power at peak times, which is the current suggestion for dealing with the shortfall. That is on top of the £10 billion which Danny Alexander offered last week as a guarantee to EDF Energy for building a new nuclear power plant in Somerset – though I'm afraid I missed the explanation of why the taxpayer should be expected to indemnify a company wholly owned by the French state, and which has annual revenues of more than £4bn.

Part of the problem, no doubt, lies in the Westminster Government's obsession with green issues, and its failure to accept that every source of energy has attendant problems of one sort or another. The Scottish Government is, of course, equally fixated on renewable technologies, but it has much more excuse, since hydro and wind power are – as they are not in England – actually a reasonable proposition for significantly contributing to the country's energy needs.

While renewables were responsible for 18% of Scotland's energy production – and 35% of the country's consumption – last year the environmental wheezes being promoted south of the Border are less convincing. The Green Deal energy efficiency programme launched in January, which the Government hopes will be taken up by 14 million homes by 2020, has so far managed to sign up four – yes, count 'em, four – households.

A decade ago, Britain was a net exporter of energy; now we import more than a quarter of our consumption. And yet, despite the failure of successive governments to plan for the impending shortfall, and the total inadequacy (for much of the UK) of green technologies in providing an effective replacement for coal-burning plants, a solution has presented itself just as the crisis has become evident.

The discovery that Britain's reserves of shale gas may be almost 30 times as large as had previously been thought is the kind of deus ex machina even Euripides would have been embarrassed to produce.

Yet, according to the British Geological Society, there is likely to be more than 1,300 trillion cubic feet of gas under Yorkshire and Lancashire alone. To put that into context, the UK currently consumes 3trn cubic feet of gas a year; if only 10% of the shale reserves in the north of England could be extracted in usable form, it would provide cheap, relatively clean energy for more than 43 years.

Predictably, the response to this positively miraculous stroke of good fortune – and right at the moment when it is most needed – has been at best half-hearted and at worst downright hostile.

After there were minor earth tremors when fracking, the technique by which shale gas is extracted, was tried near Blackpool, the Government imposed a moratorium, which it is only now getting round to reversing. Green pressure groups are predictably opposed, while the characteristic "Nimbyism" of the great British public is bound to ensure that proposed drilling will meet with fierce local opposition.

Almost all of this hesitancy is unjustifiable. Every potential source of energy has disadvantages as well as benefits. Even apparently environmentally pure technologies, such as wind turbines or solar panels, have a carbon cost in their construction, while large sections of the population regard them as a blot on the landscape. Nor, even in Scotland, are they thoroughly effective – the world record in efficiency for a turbine (it's located in Shetland) is not much more than half its theoretical output.

Shale gas promises to be considerably less devastating in environmental or aesthetic costs than the traditional alternatives. It may not be as environmentally friendly as nuclear power, but it has few of the attendant costs and hazards.

It is considerably greener than importing gas from the other end of Europe and, after the initial drilling and the capping of the site, its impact on the immediate environment is much less intrusive than, for example, coal mining. The minor earth tremors which seem to worry many people about the fracking process were, as no one seems to have remembered, also produced by traditional mining. And shale gas mining will not litter the countryside with the colossal bings which are such a prominent feature in much of central Scotland.

In the United States the exploitation of shale gas reserves has utterly transformed the country's energy policy, as well as having driven down prices for the consumer. It is estimated that by 2035 it will be half the country's gas production. Many observers credit the US's economic recovery almost entirely to the exploitation of shale gas. The economic impact in West Virginia alone was estimated at $1.3bn in 2009; the previous year New York state reckoned it had added $8bn to its economy.

The only question for UK energy policy is whether we can start doing the same before the lights go out.