Waste to energy plants have been greeted with great scepticism and knocked back in some areas, but what if they can produce “green cement” and the fumes can be drastically reduced? Sure they still need to be a last resort for waste as part of a transition to a circular economy but for one academic, Macquarie Capital, Phoenix Energy, the CEFC and ARENA, a new plant in Perth looks like a good option.
Kwinana, 40 kilometres south of Perth, will soon be home to the first major waste to energy facility in Australia. Despite being a “last resort” for only our most unrecoverable rubbish, University of Sydney waste expert Professor Ali Abbas said that these facilities have a role to play in Australia’s transition to a more sustainable waste management system.
The $688 million waste to energy facility to be built by Acciona and operated by Veolia is intended to help tackle the nation’s growing waste problem, while simultaneously generating energy.
The plant will be able to process 400,000 tonnes of non-recyclable “red bin” waste to generate around 36 megawatts of “pretty clean” baseload electricity.
ARENA allocated $23 million to the new facility to be built in the Kwinana industrial area, which will be co developed by Macquarie Capital Australia and Phoenix Energy Australia. The Clean Energy Finance Corporation is also committing $90 million in debt finance towards the project.
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The facility will use combustion grate technology, which according to ARENA chief executive officer Darren Miller, has not been used in Australia before but is well established in Europe and North America.
Professor Abbas, director of the Waste Transformation Research Hub at The University of Sydney said this technology is “as efficient as combustion can be”.
The plant works by taking in solid waste that can’t be recovered for any other use and feeding this into an advanced combustion chamber to create heat and energy.
He said that there “are a lot of things going on” in these waste to energy plants, with an assortment of materials such as plastic, paper and rubber going in. This means there are a complex array of compounds coming out, including hazardous chemicals and fumes such as nitrogen oxides.
But he stressed that the exhaust cleanup and capture of compounds is “very strict”. The waste to energy technology used in the WA plant is “pretty clean”, he said, and to have been granted approval the plant will likely not emit large quantities of dangerous fumes.
ARENA claims that the WA project is a “renewable energy solution” and that it conducts “out life cycle analysis on all bioenergy projects” to make sure “it only funds projects that deliver a net benefit in terms of emissions reduction.”
The project also has approval from the WA Environmental Protection Authority, and has the ability to generate large scale generation certificates (LGCs) for eligible feedstock in accordance with Clean Energy Regulator requirements.
In fact, the ash byproduct that is left behind – which is around 25 kilograms per every 100 kilograms of solid waste processed – presents another opportunity for sustainable waste management.
Green cement could be a by product of the plant
This is what the Waste Transformation Research Hub team under Professor Abbas is working on. The hub has managed to turn the ash byproduct into a green cement. Ground glass and carbon dioxide are also used to make the cement alternative.
The research team is currently testing a green cement path to “see how this stands up to over 12 months”. If the material withstands the test of time, the plan is to commercialise the product as soon as possible.
Professor Abbas also said that finding a new life for the ash byproduct can improve the financial case for waste to energy plants.
“It’s my view that these plants need to be integrated with other processes, such as our cement byproduct.
“The plants should be next to one another so that the waste from one plant becomes the feed for another one, [in this case] the fly ash for the cement product. When you have a business for multiple products it becomes much more financially viable.”
Australians uncomfortable with waste to energy
There are plants like the one in WA in many cities in Europe and China, and sometimes they are located right in the centre.
But Australians have historically been quite resistant to waste to energy technologies, particular those that involve burning rubbish.
Proposed waste to energy projects in other jurisdictions have struggled to get off the ground. For example, a proposal to build a waste to energy incinerator at Swanbank in Queensland has been met with “strong scepticism” from the Ipswich City Council interim administrator Greg Chemello, with dangerous fumes the chief concern.
Professor Abbas believes that there is a “very conservative NIMBY [Not In My Back Yard] culture in Australia”.
He said the other reason Australia has failed to adopt waste to energy until now is because we rely so heavily on landfill to manage our waste. This is a problem, and not just because countries such as China have stopped importing large amounts of our waste.
“We have had such a reliance on landfill that this restricts us from innovation. If you are throwing your waste away you don’t think about it. It reduces the innovation.”
Waste to energy only one piece of the puzzle
Professor Abbas stressed that like landfill, waste to energy is a “last resort” option reserved for waste that can’t be recovered.
“I will be very clear – this should be a last resort. [Waste to energy] is competitive with landfill in the waste hierarchy.”
“We’d love to not have a need to do waste to energy.”
He said it is important to understand where waste to energy sits in the context of the circular economy.
“We need in a circular economy to design products to use and reuse. They should have long life spans which makes them much more efficient in terms of their carbon footprint.
“Product design in the future for our society – electricity, plastic, a unit of concrete – will need to be well-designed so it can be reused. This will reduce the need for recycling because a lot of energy goes into recycling and reprocessing.”
Policy will play a key role in the transition to a circular economy, according to Professor Abbas. He said that we will need to have “circular economy certified products” in the future.