Total Otter

U.K. Block 210/15a

Landmark: World’s First Dual Electric Submersible Pumps

Project Overview

Contract Award: 2001
Sales: Kongsberg, Norway
Fab. Trees: Dunfermline, U.K.
Fab. Controls: Kongsberg, Norway
Service Base: Aberdeen, Norway
Host Type: Platform
Contract Type: EPIC

Project Characteristics

No. Trees: 6
Water Depth: 180 m (590 ft)
Tree Type: Enhanced Horizontal
Tree Pressure: 10,000 psi
Tree Bore Size: 5"x2"
Hydrocarbon: Oil/Gas

Project Ownership

Total 54%
Dana 19%
ExxonMobil 13%
Shell 13%

Scope of Work

Six (6) enhanced horizontal 5"x2" 10,000 psi subsea trees
One (1) HOST® template
Manifold system
UWD-15 18-3/4" 15,000 psi subsea wellheads and tubing hanger
Two (2) tie-in spools to main flowlines
Subsea electro-hydraulic control system
Topside controls equipment
Two (2) tie-in spools to main flowlines
One (1) well jumper to satellite well
Subsea protection structure
All required installation and workover tools and equipment
EPIC testing and installation of all equipment
System integration testing, installation assistance, service and maintenance

Comments

Otter’s location makes it one of the northern-most fields in the North Sea. It is also one of the deepest subsea tiebacks in the U.K. North Sea. It is a good example of how technical innovation and ongoing commercial effectiveness within the industry can unlock the stranded reserves of the UKCS. Otter not only adds new reserves but also extends the life of its host, the Eider Field.

Otter is a development of six (6) subsea wells which are tied back to the Shell Expro-operated Eider platform. It is located in the northern North Sea, 150 km (94 miles) northeast of Shetland in a water depth of 180 m (590 ft). Hydrocarbons are exported from Otter via the Eider platform to North Cormorant. The oil is then sent to the Sullom Voe Oil Terminal in Shetland via the Brent system, and the gas is sent to the St. Fergus Gas Terminal via the FLAGS system.

Technical innovation and the use of existing infrastructure made the development of Otter economically viable. Artificial lift, required to recover reserves from the Otter reservoir, is provided by dual subsea electric submersible pumps (ESPs). These pumps are powered from Eider by three (3) electrical cables. Installing dual ESPs in a subsea well is a world first. Otter is the longest subsea tieback installed to date using ESPs.