Crux

Crux Gas Field Project Profile

Location

The Crux gas field is located in the Browse Basin, approximately 190km offshore northwest of Australia, within the Commonwealth marine waters. Specifically, it is situated in the AC/P23 permit area at water depths of around 165 meters.

Project Participants

The project is being developed by a joint venture consisting of:

• Shell Australia Pty Ltd.: The operator with an 82% interest.
• SGH Energy (a division of Seven Group Holdings): Holding a 15% interest.
• Osaka Gas Holding: With a 3% interest.

Discovery and Reserves

The Crux gas field was discovered in 2000 and was initially operated by Nexus Energy, which is now part of SGH. The field consists of four reservoir units of the Montara, Plover, and Nome formations. It is estimated to contain two trillion cubic feet (tcf) of gas and 66 million barrels of condensate.

Development Plan

• Platform and Wells: The field will be developed using a not normally manned (NNM) platform equipped with dry trees, minimal processing facilities, and utility systems. The platform will be remotely operated from the Prelude FLNG facility. Five production wells are planned to be drilled from a single drill center, with additional wells to be drilled in the in-field development area approximately 30km from the proposed platform location. These wells will be tied back to the platform using subsea infrastructure.
• Drilling Activities: The wells will be drilled using a semi-submersible mobile offshore drilling unit and a drilling template. The template, measuring 28m in length, 9m in width, and 10m in height, will be installed by a light construction vessel.
• Export Pipeline: The gas will be exported through an undersea pipeline connecting the Crux platform to the Prelude FLNG vessel, located 160 km to the southwest.

Production Capacity and Timeline

• Production Capacity: The Crux gas field is designed to supply up to 550 million standard cubic feet of gas per day (MMscfd).
• Construction and Production: Construction began in 2022, with mobile offshore drilling unit operations anticipated to be completed by 2025. The first production of gas is expected in 2027. The field has an expected life of 20 years, after which it will be abandoned and decommissioned.

Regulatory Approvals

The project has received the necessary regulatory approvals, including a production license (AC/L10) and environmental clearance from the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA). The environmental approval was granted in August 2020, and the front-end engineering design (FEED) studies were completed in April 2021.

Infrastructure and Operations

• Prelude FLNG Facility: The gas produced from the Crux field will be processed through the existing infrastructure of the Prelude FLNG facility, which is the world’s largest FLNG platform. This facility has a production capacity of 5.3 million tonnes per annum (Mtpa) of liquids, 3.6 Mtpa of LNG, 1.3 Mtpa of condensate, and 0.4 Mtpa of liquefied petroleum gas.
• Remote Operation: The Crux NNM platform will be remotely operated from the Prelude FLNG facility, reducing the need for on-site personnel and minimizing costs.

Contractors and Partners

• FEED and Pipeline: Wood and KBR were awarded the contract for delivering the FEED for the NNM platform and gas export pipeline.
• Geotechnical Surveys: Neptune was contracted to perform geotechnical surveys for the field and route surveys for the pipeline.

Environmental Considerations

The project has undergone extensive environmental assessments and has received the necessary environmental approvals. The Crux Installation and Cold Commissioning Environment Plan outlines the environmental management strategies, including the assessment of potential impacts on the physical environment, ecosystems, and socio-economic factors. The plan also details measures for mitigating these impacts and ensuring compliance with environmental regulations.

Economic and Political Context

The final investment decision for the Crux project was made in May 2022, a time of growing uncertainty about new oil and gas projects in Australia due to the newly elected Labor Government and the influence of the Greens Party in the Senate. Despite these uncertainties, the project has proceeded with regulatory approvals and commercial viability supported by the use of existing infrastructure.