Is the North Sea a third full or four-fifths empty? And how will that translate into dollars, pounds or a new currency flowing into Holyrood’s coffers if Scotland votes for independence on September 18?
With projections of reserves forming a key part of the Yes campaign’s financial arguments for an independent state, the debate on the true scale of Scotland’s remaining hydrocarbon potential has become even shriller in recent weeks.
The Aberdeen-based billionaire Sir Ian Wood, former head of oil services supplier Wood Group, who in the past year has led a government-commissioned review into how best to exploit the North Sea’s remaining resources, has also waded in.
In a carefully nuanced interview with the trade website Energy Voice, Sir Ian said he had “no allegiance to any party or campaign”.
But, in remarks immediately seized upon by No campaigners, he warned of a sharp tail-off in production from 2030. Sir Ian acknowledged that as many as 24bn barrels of oil equivalent may remain, but he suggested 15bn to 16.5bn as a more likely total – compared with the more than 40bn extracted since the 1970s.
“Offshore oil and gas cannot figure significantly in Scotland’s medium-term economic calculations,” he said.
Oil & Gas UK, the body representing offshore operators that has been careful not to take sides in the debate, puts the range between 12bn and 24bn.
“We are very clear – we are saying there’s a wide range of possible outcomes,” said Malcolm Webb, its chief executive.
“It’s dependent on encouraging the amount of activity and investment that’s going into the North Sea. For that we need some changes – there are red lights flashing.”
Pro-independence campaigners meanwhile have pointed to estimates as high as 30bn barrels.
Predictions from the Department of Energy and Climate Change are for UK oil production to decline from 43m tonnes this year to 23m by 2030.
No campaigners have persistently impugned the £1.5tn figure cited by Alex Salmond, Scotland’s first minister, for the wholesale value of remaining UK resources, the bulk of which sits in waters the country would control if it seceded.
Along with bodies such as the Office for Budget Responsibility, opponents of independence have highlighted the vagaries of tax receipts as North Sea output drops to suggest a far more fragile basis for the calculations.
Robert Chote, chairman of the OBR, sparked controversy in July after he wrote to the Scottish parliament setting out his reasons for predicting a sharp fall in UK oil and gas receipts from £6.1bn in 2012-13 to £3.5bn by 2018-19, with far steeper declines after that.
Though DECC is predicting a flattening of output, or even a slight increase in production this decade, government agencies are assuming a 5 per cent annual decline into the next decade.
In his assessment of UK public finances, Mr Chote also revised down by a quarter, to £40bn, his prediction of aggregate North Sea receipts for 2020 to 2041. He conceded that “oil and gas receipts are the most volatile revenue streams in the UK public finances and forecasting them over even short horizons is extremely difficult”.
Mr Salmond dismissed the revisions as “stuff and nonsense”. Alistair Darling, head of the Better Together campaign, seized on the figures as evidence that “oil is running out and the tax we will get from it is falling”.
The commentary from HM Revenue & Customs in June shows the UK culled total revenues of £4.7bn from the North Sea in 2013-14. Though down on the peak of £12.4bn in the year to April 2009, that tax take was still above the £4.2bn reached a decade ago when, despite far higher production, lower oil and gas prices depressed government receipts.
With both sides keen to emphasise the predictions most likely to boost their own arguments, uncertainty over oil and gas prices adds another layer of complexity.
The OBR’s “central scenario” is a rise from $102 a barrel in 2015 to $160 by 2040 – which would help offset falling output and higher production costs.
But the OBR also points to the extremes set out by the US-based Energy Information Administration of $350 a barrel under its “high price” scenario and $120 under “low price” conditions.
Such extremes could present a famine or feast to whichever government commands the tail-end of Scottish oil revenues.
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