2.5 Gorgon

The Gorgon Project (see Figure 5) is being developed by Chevron Australia together with its joint venture partners Shell and ExxonMobil. With reserves estimated to be about 40 Tcf, the development has capacity to produce 15 Mt/yr of LNG and 300 TJ/d of natural gas from the Gorgon and Io-Jansz discoveries [21]. Each of the joint venture partners has negotiated separate sales agreements for its share of the produced gas [22]. The discoveries being produced by this project contain about 1.5 to 2.6 Tcf of carbon dioxide – the Gorgon discovery contains 14% CO2 [23]. In order to avoid large-scale emissions to the atmosphere, the Gorgon project will store 3.3 Mt/yr of carbon dioxide in a saline formation below the Barrow Island processing facilities [24].

The project is expected to cost A$43 billion [24] with the CCS component costing between A$300 million and A$400 million [25].

Figure 5 – A map of the Greater Gorgon development plan [23]

Source: Chevron, (2005). "The Gorgon Project" In: Proceedings of the 2005 Annual CO2CRC Research Symposium, Barossa Valley, Australia, November 2005.

The Gorgon discovery is in 200 m of water and Io-Jansz discovery is in 1,300 m around 130 km from the Australian mainland [25]. The discoveries will be produced by subsea completed wells and tied back to Barrow Island 70 km from the Australian mainland. The gas will be processed in three 5 Mt/yr LNG trains with some gas being exported to the domestic market [21].

The scale of CO2 storage planned for the Gorgon project will make it the largest of its kind in the world. The project [8] will involve the reinjection of 2.7 to 3.2 Mt/yr CO2 extracted from the discovery gas into the Dupuy Formation 2,300 m below Barrow Island. CO2 will be separated from the produced gas at the gas-processing facility on the island, compressed to a supercritical state, and then transported by a 12 km pipeline to the injection site for storage. The development plan calls for approximately ten injection wells with additional monitoring and water relief wells. A total of 125 Mt CO2 is expected to be stored over the life of the project.