Macedon

The Macedon domestic gas project based in Onslow, Western Australia, commercialises natural gas from BHP Billiton's offshore gas production lease that is located in the Exmouth sub-basin. First gas produced from the project occurred in August 2013 with the project being officially declared open in September the same year.

Macedon Gas Field can Suppy 200 Terrajouls of gas a day Into the Western Australian Domestic Market

The Macedon gas treatment plant, at the Ashburton North strategic Industrial Area, 17 kilometres south west of Onslow, has a production capacity of 200 terrajoules of gas a day. The gas comes from four offshore production wells.

Macedon Gas Project was BHP Billiton's Biggest Domestic Gas Project

Macedon was BHP Billiton's largest domestic gas project ever undertaken in Australia. It is expected to supply 20 percent of Western Australia's domestic and industrial gas, for the wholesale market, until 2033.

Macedon's Sub-sea gas is Brought to Shore in a 75 Kilometre Long Pipeline

The gas, from the under-sea gas fields, is piped through a 500 mm pipeline for 75 kilometres offshore and 15.5 kilometres onshore, to reach the Ashburton North gas plant. A 67 kilometre tie-in pipeline connects the gas plant to the Bunbury/Dampier Natural Gas Pipeline.

Six Hundred Employed on the Macedon Gas Project

BHP Billiton employed over 600 people, either directly, or indirectly through contractors, to work on the Macedon gas field development. Ten percent were Indigenous Australians. The Macedon domestic gas project is a joint venture operation with BHP Billiton having a 71.43 percent interest and Apache Northwest having a 28.57 percent interest. Structural, mechanical and piping installation at the onshore gas plant at Ashburton North was undertaken by Monadelphous Group.

Macedon Gas Project Planned in 2010

BHP Billiton announced in September 2010 that it planned to develop the Macedon gas field in the Exmouth Sub-basin. The four offshore gas production wells that are situated 100 kilometres west of Onslow, have recoverable gas reserves of between 400 and 750 billion cubic feet of natural gas. Proposals to go ahead with the development of the Macedon gas field were subjected to a wide ranging environmental assessment process that entailed extensive consultation with key stakeholders and local community groups.

BHP Billiton discovered the Macedon gas field off the Western Australian coast west of Onslow over 20 years ago but all thoughts of developing the find at that time were abandoned during the 1990's, when it was unable to have the gas accepted into the Western Australian domestic market. It was found the Macedon natural gas was of a lower quality than that of the Western Australian state governments main supplier on the North West Shelf. It therefore wouldn't allow Macedon gas to be fed into into the same pipeline that distributed the North West Shelf gas to the domestic market. However, the government has had to change this ruling as massive gas supply contracts with the North West Shelf are now beginning to expire and it has become apparent a future gas shortfall in domestic gas supply was imminent. The gas available from the Macedon gas fields is now considered suitable to fill the supply gap.