Figure 1. UKCS Production.
All figures courtesy WGEG.
Base production 2012-2017 fields onstream Sanctioned projects
18 Offshore August 2017 • www.offshore-mag.com
UK oil and gas outlook – can exploration
drilling deliver tomorrow’s production?
Industry must identify larger targets to replace reserves
In recent years, the UK’s offshore oil and gas production has risen with 49 new fields coming onstream since the start of 2012. At the same time, as various large projects move into the development and
production phase, the number of unsanctioned
but potentially commercial discoveries has
Westwood Global Energy Group (WGEG)
estimates there are close to 8. 4 Bboe of re-
sources remaining in 491 unsanctioned discoveries across the UK continental shelf (UKCS),
but only 30 (just over 1 Bboe in total) appear
to be potentially commercial. The majority
are progressing toward sanction but there
is very little in the development hopper that
can slow the production decline. As a result,
there is a need for fresh exploration to deliver
material volumes if the UK is to replenish its
commercial pool of discoveries. Although
various large prospects are likely to be drilled
this year, many are either high-pressure/high-temperature (HP/HT) or stratigraphic traps,
and therefore inherently riskier.
Total UK production1 looks set to increase
from around 1. 68 MMboe/d in 2016 to just
over 1. 8 MMboe/d in 2018, continuing the
year-on-year increase that started in 2013.
Production efficiencies and field redevelop-
ments have played their part but it is the
new development projects that have made
the greatest contribution. New fields either
recently onstream or close to start-up include the heavy-oil projects of Kraken (127
MMbbl) and Mariner (250 MMbbl) in the
East Shetland basin; the HP/HT Culzean field
(275 MMboe); and large, more conventional
developments such as Catcher (around 100
MMboe), Cygnus (932 bcf, or 155 MMboe)
and the west of Shetland Quad 204 redevelop-
ment (around 450 MMboe). The proportion
of new developments considered technically
complex is rising, and this includes heavy
oil, HP/H T, deepwater and tight gas projects.
WGEG estimates that 37% of all reserves that
have come onstream since 2012 or are under
development are challenging to deliver.
The production decline will be most notice-
able in the UK North Sea, where output is likely
to fall by 30% from the current 1. 5 MMboe/d to
1 MMboe/d by 2021. In contrast, the west of
Shetlands should see an increase from 120,000
boe/d in 2016 to over 300,000 boe/d by 2020,
and this region looks set to account for around
a quarter of the UK’s total production in the
early 2020s, compared to just 8% in 2016. This
is due largely to start-ups at fields such as Clair
Ridge, Edradour and Glenlivet, and production
building from the redeveloped Schiehallion and
Loyal fields (Quad 204).
Development of these large-resource fields
will lift production in the short term, but WGEG
predicts a rapid decline from 2020. While every effort will be made to maximize recovery
from existing developments, there will be an
increased reliance on tapping the potential
of the UK’s already discovered, but yet to be
sanctioned, smaller discoveries. And while
smaller, near-field tiebacks provide value for
operators of the associated infrastructure, they
lack the scale and longevity afforded by many
of the current large developments.
The 491 undeveloped discoveries with total
resources of 8. 36 Bboe are dominated by unap-
Westwood Global Energy Group
Ten largest developments sanctioned onstream within the last five years.
Field Area Discovered
(mmboe) Reservoir First oil
Clair Ridge WOS 31/03/1978 619 248 660.3300171 Normal Under dev.
Culzean CNSN 02/12/2008 42 1,398 275 HP/HT Underdev.
Mariner NNS 05/06/1982 248 0 248 Heavy oil Under dev.
Laggan WOS 1986 9 976 171.67 Deepwater 08/02/2016
Cygnus SNS 2006 0 932 155.33 Conventional15/12/2016
Golden Eagle CNSN 2007 148 27 152.50 Conventional 01/11/2014
Jasmine CNSS 2006 51 491 132.83 HP/HT 01/01/2014
Kraken NNS 1985 127 0 127.00 HeavyOil 23/06/2017
Breagh SNS 1997 1 452 76.33 Conventional14/10/2013
Tormore WOS 2007 18 251 59.83 Conventional08/08/2016