Chevron to proceed with $4-billion Jansz-Io compression project

July 12, 2021

Chevron Australia has reached a final investment decision (FID) on a $4-billion project to add compression to maintain gas flow from Jansz-Io fields in the Carnarvon basin off Western Australia.

Jansz-Io, discovered in April 2000, lies some 200 km offshore the northwestern coast at water depths of 1,400 m.

Describing the development as a modification of the existing Gorgon development, Chevron said compression work will include construction and installation of a 27,000-tonne normally unattended floating field control station along with 6,500 tonnes of subsea compression infrastructure and a 135-km submarine power cable linked to the operations base on Barrow Island.

Construction and installation are expected to take 5 years to complete. Work will begin in second-half 2022.

Jansz-Io compression work follows the Gorgon Stage 2 project which is nearing completion of the installation phase to supply gas to the Gorgon LNG and domestic gas plants on Barrow Island from four new Jansz-Io and seven new Gorgon wells.

A contract was let to Aker Solutions to cover engineering, procurement, and construction (EPC) of the all-electric subsea gas compression system. It also includes interface responsibility, and assistance during installation and commissioning. The subsea gas compression system will include a complete compression station with three compressor modules and two subsea pump modules, all-electric control systems and actuators, structures including mud mats, high-voltage electrical power distribution system, several spare modules and equipment and various associated tooling. Work starts immediately with delivery expected during 2025.

Chevron is operator of the Gorgon project with 47.333% interest. ExxonMobil and Shell each have 25%. Osaka Gas holds 1.25%, Tokyo Gas holds 1%, and JERA holds 0.417%.