Renewable energy

Sydney Water recently implemented a Renewable Energy Generation (REG) Program as part of its pledge to be carbon neutral by 2020. The program aims to reduce greenhouse gas emissions by approximately 54,000 tonnes per year, this is equivalent to 12.5 per cent of Sydney Water’s total emissions.

Under the project, Sydney Water installed five biogas cogeneration facilities and three hydro-electric generators at wastewater treatment plants and pipelines across Sydney.

Projects such as the REG Program are a step closer to sustainability in the delivery of Sydney Water's services, and an important step towards reducing the impacts of climate change.

Cogeneration

As part of the REG program, Sydney Water installed five cogeneration plants at the treatment plants listed below. All five cogeneration plants are now fully operational, using state-of-the-art combustion technology to convert biogas, a product of the wastewater treatment process, into electricity.

• Bondi Wastewater Treatment Plant
• Glenfield Water Recycling Plant
• Liverpool Water Recycling Plant
• Warriewood Wastewater Treatment Plant
• Wollongong Water Recycling Plant

As part of the previous program, Sydney Water installed cogeneration facilities at Malabar, North Head and Cronulla Wastewater Treatment Plants. Malabar's cogeneration unit, the first renewable energy initiative, commenced operations in 1999. These plants also use biogas (methane) as the fuel source. The cogeneration systems produce both green electricity and heat.

Since the Malabar and Cronulla cogeneration plants commenced operations in the early 2000's, they have produced over 130,000 megawatt hours of electricity each year, displacing approximately 130,000 tonnes of greenhouse gases.

The cogeneration unit at North Head commenced operations in 2008 and has a capacity of 1.4 megawatts. It can produce up to 12,000 megawatt hours of electricity each year, which is equivalent to removing 3,000 cars off the road.

Hydro-electricity

Hydro-electric energy is produced by using energy from treated wastewater and water flows.

As part of the REG Program, Sydney Water installed three hydro-electric generators at:

• North Head Wastewater Treatment Plant
• Woronora Water Filtration Plant
• Prospect Reservoir Pipeline

These generators capture energy from the flows of water or treated wastewater travelling through a shaft or pipe. A hydroelectric turbine is joined to a generator, which converts the rotational energy of the turbine into electrical energy.

The hydro-electric generator at North Head Wastewater Treatment Plant is the first of its kind in Australia generating power from treated wastewater. The combined capacity of both the cogeneration and the hydro -generator at North Head is about 3.4 megawatts. These plants will generate about 20,000 megawatt hours of electricity each year, providing over 40% of the Plant's own power. You can see how this works in our video about the North Head improvements (WMV - 8314KB) .

The Prospect hydro-electric generator is the largest of Sydney Water's renewable generation projects with a capacity of over 3.5 megawatts, producing around 20,000 megawatt hours of electricity each year.