The site

The Pioneer cogeneration project was commissioned in 2005 at Brandon following an intense 36 month period of project development, implementation and testing. The site is centrally located in the Burdekin sugar growing region. The project developed in two distinct parts:

1. Mill efficiency works (MEW) - designed to improve the energy effectiveness of the sugar production process to maximise the production of excess surplus bagasse for the generation of electricity;

2. Power plant (PP) - designed to generate electricity efficiently from the excess surplus bagasse made available from the MEW.

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Since commissioning, the new plant and its operation are now reaching full stride, with many of the new processes bedded in. Work now focuses on improving efficiencies and cost effectiveness of the plant and the new processes employed. Operations at the plant revolve around two distinct operating periods - the crushing season (June - November) and generation season (December - March).

Technology

While the Pioneer cogeneration project principally utilises tried and tested sugar industry technology, it does encompass some new sugar industry developments. These include:

The installation of horizontal wet arrestors that save space and reduce stack emissions; The installation of a high-pressure 65-bar boiler and closed-water-circuit-condensing turbine that allows independent operations from sugar production processes during the non-crushing period; efficient generation from limited fuel sources; and, low-emission technology; Sugar mill efficiency work that includes electrification of all mill drives; ash dewatering, drying and storage system that reduces ash waste volumes; and, a neutralisation tank in service area that reduces environmental risk.

Fuel handling has evolved significantly since the project’s implementation. Driven by the scale of new operations and the economic necessity for reliable, good and clean fuel, fuel handling has been transformed through the employment of new processes and equipment. The project now consumes more than 600,000 tonnes of bagasse per year, with more than 100,000 tonnes reclaimed during the generation season. The plant has no other auxiliary fuel source apart from bagasse. Consequently, effort is taken to ensure the bagasse is transferred, stored and reclaimed to minimise the degradation of its fuel quality and to mitigate the risk of spontaneous combustion. The bagasse stored for reclamation during the generation season is stored on constructed pads, under cover and in long thin piles.

Energy purchase and supply

Pioneer Mill is registered as a non-scheduled, non-market generator. The plant generates electricity at 11,000 kilovolts (kV) and exports into Ergon Energy’s 66 kV distribution system in the Clare region. The generator is an accredited generator under the Mandatory Renewable Energy Scheme.

Environmental impact

Since 2005, the project has greatly reduced the environmental impact of excess surplus bagasse storage and stack emissions in the region. Pioneer Mill now boasts one of the lowest stack emissions in the Australian Sugar Industry. CSR is committed to reducing green house gas emissions and has extended its involvement in Greenhouse Challenge Plus to all of CSR’s operations. Annually, the project offsets more than 190,000 tonnes of CO2 equivalent (the equivalent of taking over 40,000 cars off the road or supplying 16,000 homes with power for a year).

Success of the project to date

In 2007, Pioneer Mill was the third-largest renewable energy generator in Australia and the flagship in CSR’s energy-generation portfolio. The project highlights what is possible in terms of electricity generation from the sugar industry using bagasse as the renewable fuel source.