BP looking to maximize production
from Shetland area fields
Aerial view of the
Sullom Voe terminal.
All images courtesy BP.
Offshore facilities investments underline area’s long-term potential
Some large-scale projects are under way throughout the UK North Sea, reminiscent of the early days in the 1970s. None, though, are as coordi- nated and wide-ranging in scope as
BP’s programs on its felds in the far-north
Shetland area. These vary from comprehensive overhauls of facilities west of Shetland
to a life extension of Magnus in the east,
one of Britain’s longest-producing felds. In
between, the Phase 2 development of the
Clair feld will take its production to a much
higher level, while at the associated Sullom
Voe terminal, new gas facilities are planned
to help streamline offshore production.
Foinaven is 190 km ( 118 mi) west of the
Shetland Islands in blocks 204/19 and 204/22.
The feld was discovered in 1990. When development was sanctioned four years later, it was
the frst UK oil and gas feld development in
the Atlantic Margin, and the sea depths of 330-
520 m ( 1,082-1,706 ft) were at the time considered deepwater. First oil was produced in 1997
with all 20 Phase 1 wells in service by 2000,
including BP’s frst offshore multi-laterals.
The feld is produced via the FPSO
Petrojarl Foinaven, formerly a Russian submarine
tender ship which was converted at the Ferrol shipyard in northwest Spain. The 240-m
(787-ft) long turret-moored vessel, operated
by Teekay on BP’s behalf, has never had
to be taken off station despite the periodically severe wave conditions. The vessel is
to remain in service into the next decade
as BP reviews options to extend feld life.
In 2011-12, however, BP and partners Shell
and Marathon invested £ 100 million ($151
million) in replacing parts of the feld’s 8-in.
subsea pipeline network, which did require
upgrading after 15 years in operation.
Petrojarl Foinaven is connected to fve subsea drill centers with 43 wells, including 14 for
water injection to enhance production. The vessel has an onboard storage capacity of 280,000
bbl. Oil is transported by two dedicated shuttle
tankers direct to the refneries of northwest
Europe. Gas produced with Foinaven’s oil was
compressed from the outset, initially for reinjection and for power generation on the vessel. In
2001, a new pipeline was installed, which since
mid-2002 has exported commingled gas from
Foinaven and Schiehallion to Sullom Voe. Another subsea pipeline takes the gas northeast to
the Magnus feld for use in a water-alternating-gas injection scheme.
Since start-up, Foinaven has delivered 335
MMbbl of oil, according to Peter Miller, BP’s
vice president, midstream.
Quad 204 redevelopment
Schiehallion/Loyal are mainly in blocks
204/20 and 204/25 in 350-450 m ( 1,148-1,476 ft)
of water, and 175 km ( 109 mi) west of Shetland. Schiehallion was discovered in 1993,
with recoverable reserves at the time estimated at up to 500 MMbbl; Loyal was discovered to the north a year later. Following
an extended well test of both felds, the UK
government sanctioned a combined £1-bil-
lion ($1.51-billion) development in 1996 via
a newbuild FPSO, capable of producing up
to 220,000 b/d of oil and 140 MMcf/d of gas,
with oil storage capacity of 950,000 bbl.
Oil production started in summer 1998,
with oil transported to Sullom Voe via BP
Shipping’s purpose-built shuttle tanker Loch
Rannoch. Due to the proximity to Foinaven,
15 km ( 9. 3 mi) to the southwest, the two
production centers shared support facilities
such as helicopters and supply vessels. However, that arrangement ceased early this year
when operations were shut down to allow the
existing Schiehallion FPSO to be shut down
and disconnected, as the frst step of the