Townsville Citiwater Biogas Project

Grid-connected cogeneration, renewable
Location: Townsville, QLD

Primary fuel and supplier

Biogas from anaerobic digestion of sewage sludge is provided from the Citiwater Cleveland Bay and Mount St John sewage plants, both in Townsville city.

Prime mover

Spark ignition, six cylinder MAN reciprocating engines driving Stamford synchronous, brushless alternators.

Heat recovery

Full heat recovery of hot water at 90 o C from engine jackets and exhausts, which is then used in heating sludge in the digestors to accelerate the anaerobic digestion process and the production of methane for the generation units.

Energy offering and environmental impact

Both biogas cogeneration plants are designed to use 100 per cent of the gas produced by the digestors and will operate 24 hours, seven days a week. The units will be able to provide more than 90 per cent of the power requirements of Mount St John and 30 per cent of the power needs of Cleveland Bay, displacing power supply from the grid. Each unit will produce about 880 MW/h of power per year, increasing reliability of supply.

Combined, the units will generate enough energy to displace 700 tonnes of carbon dioxide emissions from coal-fired power stations per annum.