Quarantine Power Station expansion
Stage 4
Overview
Origin currently owns and operates the Quarantine Power Station on Torrens Island, just north of the Adelaide CBD in South Australia. The original four turbine gas-fired power station has a capacity of 95MW and is located a few kilometres north of the much larger Torrens Island Power Station.
Origin also has Development Approval to expand the original power station further by adding a steam turbine to generate power using the heat produced by the exhaust from the existing generators. However, this project is yet to be approved by the Origin board. The addition of a steam system and steam turbine would only be appropriate if the power station was expected to run for significant periods of time.
Further expansion
However, in the current electricity market, the requirement is for capacity which generates only during short term peak demand periods.
In order to meet this growing demand for peak electricity in the region, Origin decided to expand the capacity of the Power Station by adding a gas turbine generator adjacent to the existing plant. The new generator has a nominal capacity of 120MW, which is roughly the equivalent of the average power use of 75,000 homes. When combined with the existing installation, Quarantine will supply peaking power to more than 130,000 homes.
The older and new generator sets will all operate as a “peaking” power station instead of running continuously as the electricity demand in South Australia can vary significantly for short periods of time. This is particularly true during the hot summer, when air conditioner use rises dramatically.
Project construction
The State Government granted approval for expansion of Quarantine Power Station early in 2007.
In May 2007, Origin executed an agreement with General Electric for the supply of a 9E gas turbine generator set. The 9E is a proven and reliable machine, with low emissions technology. Similar generators are in use throughout the world and Origin already has an interest in two similar generators installed at the Worsley Alumina Refinery in Western Australia, and the Osborne Cogeneration Plant located across the Port River from the Quarantine Power Station.
On 27 July 2007, Origin signed a contract with Leighton Contractors Pty Ltd for the civil works, installation and balance of plant for the station's expansion.
Preliminary site preparation work began in late 2007. The main Power Station construction work started in mid-2008 with over 1100 tonnes of natural gas-fired power generation equipment delivered to site. Plant commissioning and operation will occur in the summer of 2008/09.
The generator was delivered through the Port of Adelaide and installed by Origin’s contractors on a pre-prepared concrete foundation adjacent to the original four turbines.
The project required additional work to upgrade the electrical connection at Quarantine and the addition of a connection to the SEA Gas pipeline which runs to the west of the site.
Project impact
The decision to expand the existing Quarantine Power Station was made because it means that additional electricity generation capacity can be added with minimal impact on the community and environment.
The greenhouse gas emissions impact of the new generator is expected to be low. The gas-fired generator is expected to run for only a small proportion of the time. Gas fired power stations produce significantly lower levels of greenhouse gas than the average for existing generation.
The extra peaking capacity will add to the security of electricity supplies in South Australia and will assist Origin in balancing its risk exposure in the South Australian market - one of the peakiest in the world.
