As of 1 January 2017, the UKCS holds 6 billion boe in recoverable reserves, of which 5.3 billion boe – 88% – lie in Scottish waters.
This split has been calculated by Edinburg-based hydrocarbon analysts at Wood Mackenzie using the Scottish Adjacent Boundary Order 1999, and includes producing fields, fields under development which will start production soon and the ready-to-go pre-FID projects.
Based on this reserves calculation, a pre-tax standalone NPV (1 Jan 2017) of £44 billion for the fields in Scottish waters.
A spokesman explained: “We hold a further 4.3 billion boe of contingent resources for Scotland, some of which may be upgraded to reserves depending on a number of factors, including cost reductions and oil price.
“We hold a further 1.3 billion boe of yet to find resources for Scotland, those which are undiscovered. However, this is an estimate of undiscovered volumes and is the most uncertain category, especially as exploration drilling is at an all-time low.
“While 11 billion boe of reserves and resources lie in Scottish waters, this sits alongside the obligation to decommission the majority of fields, equating to 80% of the total UK decommissioning bill.
“Since the 2014 <Scottish) Independence referendum, commercial reserves have decreased by about 30%. This is chiefly due to 1.6 billion boe of reserves produced being replaced with just 0.1 billion boe of commercial discoveries.
“It is clear that oil and gas tax revenue will play a smaller part in the economic case for Scotland’s independence should a second referendum be held
“However, companies will be looking for reassurances that, should Scotland vote for independence, they will continue to have access to the decommissioning tax relief they currently receive.
“ With new investment and jobs at stake, and the complicating factors of boundaries and decommissioning tax relief, much is at stake.
Currently British government tax receipts from the North Sea are negative, as companies receive more in decommissioning rebates than they pay in tax.