Victorian Wholesale Gas Market
The Victorian Declared Transmission System (DTS), which includes the South West Pipeline (SWP), is designated as a declared wholesale gas market under the National Gas Law. This does not include SEA Gas and the Eastern Gas Pipeline. The operation of the Victorian wholesale gas market is governed by the Declared Wholesale Market Rules (DWMR) which is a subset of the National Gas Rules.
The Victorian Gas Market is unique in Australian in that it operates under a market carriage model. This means that market participants are not required to have firm capacity rights in order to transport gas through the declared Victorian gas transportation system. Instead, Market Participants inject gas that AEMO schedules, which is derived from price and volume bid stacks at gas facilities and interconnecting pipelines.
A large proportion of Victorian gas load is for domestic and commercial heating. Therefore demand is highly seasonal. The SWP typically delivers less than 50 TJ/day to Melbourne during summer and shoulder seasons, and flow is sometimes reversed to flow back to Iona. During winter (June to August) and into September, SWP flow rates to Melbourne are typically in the 200 to 300 TJ/day range. There are approximately 10-15 peak injection days each year when the SWP flow is greater than 300 TJ/day.
South Australian Gas Market
Iona can deliver gas into the South Australian gas market via the SEA Gas pipeline. South Australia is also supplied by the Moomba Gas Plant via the Moomba Adelaide Pipeline (MAP). This allows gas from the Otway Basin and other Victorian producers to provide gas to South Australia.