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The biogas plant at the WMRC Transfer Station.

Early nights and late rises is one way to beat Western Australia's gas crisis. Another is to develop a new way of producing energy from biodegradable wastes dumped in landfill sites across Perth.

Murdoch University researcher Lee Walker is part of team refining a bacterial recipe for a new bioconversion process that promises to change the way municipal waste is disposed of and processed - without carbon dioxide emissions and high infrastructure costs.

Part of a PhD project that emerged after 20 years teaching maths and chemistry and inspiring young people to pursue careers in science and technology, the groundbreaking work has led to the construction of the first commercial biogas plant in Subiaco.

The plant opposite the existing Subiaco wastewater treatment plant will process 50,000 tonnes a year for the Western Metropolitan Regional Council.

"There are a variety of processes around the world dealing with the reuse of organic wastes," the 47-year-old father of two told ScienceNetwork WA.

"What makes this unique is the small footprint it occupies. It is vertically built and it can be installed alongside existing waste transfer stations."

Walker's PhD studies focus on converting biodegradable wastes into a valuable resource, such as biogas, which can be produced while converting most landfill wastes into high quality compost.

He has been perfecting a composting process, DiCOM, developed by Technology Park-based company AnaeCo Ltd. It uses two groups of naturally occurring micro-organisms that until recently were believed not to be able to co-exist.

One of the groups uses the oxygen in the air and the other works in the absence of air (aerobic and anaerobic).

The second group - known as ‘work-horses’ - degrades wastes and produces renewable energy in the form of biogas.

The anaerobic phase produces a supply of methane that fuels an electrical generator to supply electricity to drive the processing equipment. Non-degradable material is removed using a mechanical sorting process at the ‘front end’ of the DiCOM process.

"The DiCOM process is not designed to take all waste," he said. "It is a rapid process which takes out all of the easily degradable waste."

Walker said the two groups could also be tweaked to work together to improve the bioconversion process: “The environmentally friendly process is operated in a completely sealed tank where compost and biogas can be collected.

"The biogas is then turned into electricity and used to meet the energy requirements of the facility. If the two groups of micro-organisms don't work in harmony, the system is out of balance."

Surplus green energy produced by the composting process can be fed back to the electricity grid to be made available for community use. AnaeCo is hoping to export the WA technology to the United Kingdom, and the company has recently put in a tender for a second Australian plant in Victoria.

Knowledge from Walker's research would allow the DiCOM process to effectively deliver environmental benefits such as rapid waste processing, renewable energy generation and minimise wastewater production.

He is based at the Environmental Biotechnology CRC, which develops advanced technologies based on biological systems to improve efficiency and reduce, and use waste to benefit a range of industries and the environment.

Research into renewable technologies has also earned two other Murdoch PhD students, Kayu Cheng and John Hunt, international Huber Technology Prizes.

The prizes honour ideas, concepts and research into the reuse of energy and valuable materials from wastewater.

Cheng won a trophy for developing a way to produce electricity from wastewater using a microbial fuel cell, and Hunt won a trophy for developing software that can rate water use efficiency on different types of land developments.

The Huber Technology Foundation supports science and research in the field of sustainable water management and creation of public awareness and enthusiasm among young engineers.