In 2013, Prysmian was awarded a contract worth more than $100 million for the supply and installation of submarine cables in deep water for a section of ExxonMobil’s existing offshore operations in the United States.

Project Overview

The scope of work involved the replacement of approximately 50 km of submarine power cables with increased capacity 40 kV EPR submarine cables, designed for water depths of up to 450 meters. The cables are supplying electric power from the existing shore-based generating plant to offshore platforms in the Santa Barbara Channel off the coast of California.

Longitude’s Scope of Work


  • Industry standard software OrcaFlex used for all installation analyses combined with automation scripts and bespoke tools developed exclusively by Longitude
  • Cable lay and stand-by analyses relating to three submarine power cable installation operations for the electrical distribution system for ExxonMobil’s Santa Ynez Unit (SYU) offshore operation in water depths from 10m to 430m
  • First end and second end pull in analyses relating to cables used in the electrical distribution system feeding SYU
  • Foreshore pull in analysis
  • Conduit pigging load analyses – assess the maximum pulling tension required

Design Engineering

  • Design of the quadrant for the export cable pull in winch line routing from the export J-tubes to the winch located on  SYU
  • Provided with the general arrangement and structural drawings of the proposed winch line route
  • Completed the design and analysis of support structure for various ancillary pull in rigging components including sheaves and padeyes