About the Project
Shaw River Power Station Pty Ltd (Shaw River Power), a wholly owned subsidiary of Santos Ltd (Santos), proposes to develop a gas-fired power station in southwestern Victoria near the town of Orford, approximately 200 kilometres south-west of Melbourne. The project comprises a power station, a gas pipeline from Iona to Orford and two water supply pipelines from Port Fairy to Orford.
The power station will be developed in stages to a peak capacity of 1,500MW. The power station will operate as a baseload, intermediate or peaking generator and will connect to the Victorian electricity grid via a switchyard1 adjacent to the Moorabool–Portland 500kV overhead transmission line. It is likely to be supplied with gas from Santos’ gas reserves in the Otway and Gippsland basins and other basins in eastern Australia.
The proposed Iona–Orford Pipeline (the gas pipeline), an approximately 100-kilometre underground gas pipeline will deliver gas to the power station from the Victorian gas transmission system near the Iona and Otway gas plants. It will connect to the South West Pipeline, east of Otway Gas Plant, and will cross predominantly rural land to the power station site near Orford.
Wannon Water proposes to build, own and operate two new underground water supply pipelines, each approximately 30 kilometres long. The water supply pipelines will supply amenity (domestic) and process (recycled) water from Wannon Water’s facilities at Port Fairy to the proposed power station.
Site and pipeline selection process
The proposed power station site and pipeline route are the product of a rigorous selection process that has considered environmental, social and technical issues. A Geographic Information System was used to collate all available information, which was analysed to identify constraints affecting site and route selection.
A physical constraint affecting the power station site and pipeline route selection is the Stony Rises, a volcanic feature comprising lava flows, marr volcanoes2 and basalt formations. Other constraints included the need to position the proposed power station in close proximity to the Moorabool–Portland 500 kV transmission line from Derrinallum to Heywood.
Following detailed assessment, sites adjacent to Darlington and Orford were favoured. The Stony Rises and water supply were major factors in this decision. Further consideration of water supply options resulted in the Orford site being chosen.
Shaw River Power proposes to use recycled wastewater from the Port Fairy water reclamation plant, reducing the need for disposal via the existing ocean outfall. Wannon Water will design, construct, own and operate the water pipelines.
Shaw River Power considered routes along existing gas pipelines in the region and, where possible, aimed to locate the pipeline adjacent to existing pipelines to limit impacts on land use and ecosystems.
A feasible route that generally follows the SEAGas pipeline before diverting to follow the Western pipeline to Orford was identified. An issue in the section between the Curdies River and Merri River was the number of ‘pinch points’. Pinch points occur where, due to a physical feature, there is not enough room for the pipeline to be placed, nor for the construction teams to work, without affecting the feature or environmental value.
Shaw River Power's eventual choice is a route to the north which avoids constraints caused by residences, outbuildings, remnant vegetation and existing gas infrastructure, and this has been the focus of studies.
1 Enabling connection equipment that allows the electricity generated by the power station to connect to the electricity network.
2 Marr volcanoes are features formed by volcanic eruptions. They typically comprise a crater lake surrounded by an ash, basalt and lava caldera or rim. There are approximately 40 marr volcanoes in the region with the most prominent being Tower Hill near Koroit.