By Justin Field and Norman Thompson
The City of Sydney's trigas generator scheme is being built by Origin - Australia's largest coal seam gas producer. What happened to the transition to biogas, ask Norman Thompson and Justin Field
Read part one of Norman Thompson and Justin Field’s story on Sydney’s trigas scheme here.
Sydney Council’s Sustainable Sydney 2030 plan targets a 70 per cent reduction of greenhouse gas emissions from 2006 levels. At the centre of the plan is a trigeneration (trigen) network across the city that will burn gas to deliver electricity, heating and cooling to city buildings.
The aims of the plan are commendable and emission reductions on this scale are needed Australia wide. But the implementationvia a trigen network that will be built and maintained by Australia’s largest coal seam gas company (CSG), Origin Energy, raises serious questions about its ability to achieve the emission reduction targets.
According to the City’s Trigeneration Master Plan, council has "resolved that by 2030 renewable gases from waste and other … sources will replace fossil fuel natural gas in the trigeneration systems". This means that until that time CSG, which currently makes up around 5 per cent of NSW supply, will be used to power the system.
The plan suggests the City has identified sufficient waste-derived renewable feed-stocks to generate and supply biogas to the trigen system, however it acknowledges the plans for moving to renewable gas are yet to be finalised.
In April 2012 Sydney Council signed an agreement (pdf) with Origin Energy’s totally owned subsidiary Cogent Energy to begin building the trigen system. Under the agreement "Origin will be responsible for the ongoing operation and maintenance of the trigen plants".
Origin Energy has a 37.5 per cent stake in Australia Pacific LNG which is constructing a Liquified Natural Gas (LNG) plant at Gladstone in Queensland. Origin is responsible for construction and operation of the project’s CSG fields.
Neither Origin nor Cogent have notable experience in biogas projects and Origin promotes itself as Australia’s largest producer of coal seam gas.
Denmark's largest biogas plant, Lemvig