The circular economy refers to the transition away from the current linear model of ‘take, make and dispose’ towards a more efficient and sustainable one – one that uses resources efficiently, prioritises renewable inputs, maximises a product’s lifetime, and captures and repurposes what was previously regarded as waste. Here, we explore the role of utilities in moving from business models that prioritise resource drain to ones that value resource gain, and some of the projects and initiatives already underway.
As defined in a 2019 PwC report, The road to circularity, circular thinking decouples economic activity from the consumption of materials and energy by creating closed-loop cycles in which waste is minimised or even eliminated, and in which resources are reused.
The COVID-19 pandemic has accelerated a host of transformative trends, such as remote working, automation and digitisation, however, urgent action is required to mitigate the intensifying challenges brought on by climate change. A circular economy can reduce the pressure on resources and help decarbonise a range of sectors, while providing a strategic and effective way to identify both cost-saving and value-creation opportunities.
Circularity also offers an opportunity to develop more transparent supply chains that add value by enhancing feedback, collaboration and a mutual exploration of sustainable avenues for growth throughout the value chain. This is particularly important as trust in corporations continues to erode, and public sentiment demands more environmentally and socially responsible business practices.
Utilities have the potential to play a huge role in the development of a circular economy, and many of the technological developments that could accelerate circularity are within their sphere of operations, such as electrification, resource recovery, hydrogen production, and carbon capture and use.
The rise of renewables
One of the key strategies in the development of a circular economy is prioritising renewable outputs, and replacing fossil fuel generation is just one way to apply circularity principles to a company’s value chain. This switch to renewable energy is a crucial element of circularity, and an increasing number of companies are seeking to reduce costs, increase sustainability and deliver long-term strategic value by making the change.
The utility industry is emerging as a major player in supplying renewable energy to industrial operations, meaning energy companies are at the heart of supporting the transition to a circular economy through the provision of renewable energy. One renewable source that has the potential to replace fossil fuels in all energy markets is bioenergy, which is energy derived from plants, animals, and their by-products and residues.
Agriculture, farming, human habitation and forestry generate crop waste and remains, manures and sludges, rendered animal fats, used oils, and timber residues. These products are known collectively as biomass, which can be converted into bioenergy to provide power for our cities and industries, liquid biofuel for transport and biogas for the production of heat.
In June 2020, Bioenergy Australia – the peak body representing Australia’s bioenergy sector – delivered an open letter to the Federal Government, signed on behalf of thousands of organisations including AusNet services, Energy Networks Australia, Gippsland Water, Jemena, Sydney Water and the Water Services Association of Australia, advocating for biomethane injection into gas distribution networks.
Shahana McKenzie, CEO of Bioenergy Australia, said that effective utilisation of organic waste to produce energy can play a central role in the national transition to a circular, low-carbon economy.
“A bio economy is circular by nature as it regenerates CO2 and encompasses the conversion of renewable biological resources into high-value products and chemical building blocks, fuels, power and heating via mature or innovative technologies,” Ms McKenzie said.
“Therefore, a bio economy can significantly contribute to the circular economy by being a supplier of renewable energy (primary sources plus side streams), materials that can be well cascaded (wood, fibres) and even feedstock for plastics.”
In November 2020, Jemena and Sydney Water signed an agreement to produce biomethane at the Malabar Wastewater Treatment Plant in South Sydney, with the green gas used to power Sydney homes and businesses. The zero-emission, high-quality biomethane gas will be injected into Jemena’s New South Wales gas distribution network – the largest in Australia with 1.4 million customers.
The $14 million project is jointly funded by Jemena ($8.1 million) and the Australian Renewable Energy Agency (ARENA), who provided $5.9 million in grant funding, and the facility is expected to produce the first biomethane for injection into the Jemena gas network in 2022.
Jemena Executive General Manager, Gas Distribution, Dr Jennifer Purdie, said as Australia looks to recover from the financial impacts of COVID-19, circular economy opportunities have the potential to create jobs, support business growth and enhance energy security with no impact to the network or customer appliances.
“This agreement will see biomethane injected into the gas network for the first time in Australia with an initial capacity of 95TJ of renewable green gas per year, which is enough to meet the gas demand of approximately 6,300 homes,” Dr Purdie said.
“We estimate there’s at least another 30,000TJ of biomethane that has the potential to be unlocked around our NSW gas infrastructure. That’s enough to supply all our current residential customers with carbon-neutral, green gas.”
If successful, the project is expected to support wider uptake of biomethane technology by the Australian waste industry with the application expected to have broader usage than just the wastewater treatment sector. Victoria is also playing its part, with the State Government announcing funding for two Renewable Organics Networks in June 2020, which will use organic waste to produce electricity, thereby reducing waste going to landfill.
The projects, which are being delivered by Barwon Water, are designed to create a circular economy for the region’s organic waste, reduce landfill costs for councils and reduce water infrastructure energy costs for Barwon Water customers.
Construction for the Colac network, which received $240,000 in 2018, is already underway and the full facility is scheduled for completion by 2022. Once complete, the project is expected to generate enough energy to power more than 1,000 homes thanks to high-strength organic waste from the Australian Lamb Company and Bulla Dairy Foods.
The Colac site will share energy back to Australian Lamb Company as hot water, and produce enough electricity to take Barwon Water’s Colac Wastewater Treatment Plant off the grid. Work is also underway to investigate options to build a similar facility by the end of 2023 for the greater Geelong region to process organic waste collected by local councils.
In a major coup for both the water and energy sectors, researchers at Melbourne’s RMIT University announced towards the end of 2020 that they had developed a new technology that uses biosolids to produce hydrogen from wastewater, in an effort to support the comprehensive recycling of an unlimited resource – sewage.
The innovation focuses on the advanced upcycling of biosolids and biogas, by-products of the wastewater treatment process. The patented technology uses a special material derived from biosolids to spark chemical reactions for producing hydrogen from biogas.
The approach means all the materials needed for hydrogen production could be sourced on-site at a wastewater treatment plant, without the need for expensive catalysts.
The method also traps the carbon found in biosolids and biogas, which could in future enable a near zero-emission wastewater sector. As well as being used in wastewater treatment, the novel reactor has potential applications in the biomass, plastics and coating industries.
The research was supported by South East Water, which will be trialling the biosolids and biogas conversion technology in a pilot plant currently under fabrication.
Dr David Bergmann, Research and Development Managernat South East Water, said the technology had potential for adoption by the industry.
“Supporting these kinds of innovative emerging technologies is an important part of our commitment towards reduced emissions and a circular economy approach involving wastewater,” Dr Bergmann said.
Solar powering sustainable operations
A number of water utilities are looking to reduce greenhouse gas emissions and operating costs by installing on-site renewable energy generation assets. In July 2020, the first solar panel array was installed as part of the NSW Government’s four-year $15 million investment into renewable energy systems at Hunter Water’s water treatment plants and pump stations.
NSW Minister for Water, Property and Housing, Melinda Pavey, said the overall project expected to reduce Hunter Water’s carbon footprint by 7,200 tonnes of emissions per year – the equivalent of taking 1,500 cars off the road. As one of South Australia’s single largest electricity users, SA Water is working towards a zero-cost energy future – with the utility’s energy-intensive drinking water and wastewater pumping and treatment operations across the state costing $83 million in 2018-19.
SA Water embraced the opportunity to electrify its own energy sources and is investing more than $300 million to install 242GWh of energy generation from new solar arrays and 34MWh of energy storage devices across its sites. The power generated and stored on-site will reduce SA Water’s reliance on grid electricity and create a revenue stream from carefully timed sales back to the market, to offset the cost of electricity that will need to be purchased at times of peak demand or low solar productivity.
In February 2020, the Western Australian Government announced it had partnered with Water Corporation and committed $30 million over three years for solar energy projects, which will see the utility install 45,000 rooftop solar panels on around 50 of its pump stations, other buildings and borefields throughout the state.
The rooftop panels will generate the energy equivalent of powering 4,400 households, reducing Water Corporation’s emissions by around 18,000 tonnes per year. This is the equivalent of taking 7,700 cars off the road.
Yarra Valley Water recently announced it will build its second waste-to-energy plant – in addition to its award-winning ReWaste facility at Wollert – which will transform end-of-life food waste into renewable energy that will help to power its treatment facilities. Solar panels are also generating energy for Yarra Valley Water’s head office, treatment plants and electric vehicle fleet.
Combined with power from a northern Victoria solar farm, these projects are producing enough energy to meet 25 per cent of Yarra Valley Water’s energy needs, steering the utility towards meeting its target of generating 100 per cent of its own energy needs through renewable energy by 2025.
In March 2021, the utility also approved 17 new recycled products for use across its projects, advancing its commitment to transitioning to a circular economy. Yarra Valley Water Managing Director, Pat McCafferty, said that making the shift towards using more recycled products as part of its supply chain is the way of the future for the organisation.
“We’re committed to opting for environmentally friendly alternatives wherever we can, in line with our commitment to the Sustainable Development Goals and building a circular economy.”
It is worth noting that solar panel and battery technology present challenges as well as opportunities. In 2016, the International Renewable Energy Agency (IRENA) estimated there was about 250,000 metric tonnes of solar panel waste in the world at the end of that year.
Without a commitment to better recycling, yearly waste amounts by the 2050s (5.5 million–6 million tonnes) could almost equal the mass contained in new installations (6.7 million tonnes). There are also wider concerns about the global battery value chain. For example, the extraction of the raw materials needed for batteries has been linked to dangerous working conditions, child labour, poverty, and other social and environmental concerns.
As part of their circularity vision, the World Economic Forum (WEF) and the Global Battery Alliance (GBA) have committed to eliminating human rights violations and ensuring safe working conditions across the battery value chain, as well as improving the repurposing and recycling of materials.
On home soil, ARENA is exploring options to help both large-scale solar PV projects and rooftop PV customers responsibly manage their waste, announcing in October 2020 that it had awarded $15.14 million in funding to 16 research projects at six Australian universities to help address solar PV panel efficiency, overall cost reductions and end-of-life issues.
The two-year R&D projects will support solar PV in the following areas:
• Advanced silicon: improvements to the overall cost-effectiveness of silicon-based panels already in mass market production, and their production processes
• Tandem silicon: increasing the cost-effectiveness of silicon-based solar PV through the use of tandem materials
• New materials: development of new materials with the potential to either reach breakthrough cost-efficiencies, or the potential for new deployment applications
• End-of-life: new solutions, including upfront solar PV panel designs and end-of-life processing, that increase the cost-effectiveness of sustainable end-of-life management of solar PV panels
ARENA CEO, Darren Miller, said, “A key part of the funding round was finding a solution to the end-of-life of solar panels and we’re excited to see some interesting new research into this area. It’s an important part in our transition to renewable energy as we need to ensure that materials used in solar panels can be recycled or repurposed for future use.”
Making every drop count
Urban water utilities manage an essential part of the water cycle that creates healthy, liveable communities and simultaneously manage a significant proportion of the liquid and solid waste created by those urban communities.
A report prepared for the Water Services Association of Australia (WSAA) by the Institute for Sustainable Futures, University of Technology Sydney, explains that the water sector must move beyond ‘sustaining’ to ‘restoring’ the material balance and then go one step further with ‘regenerative’ actions that will ensure the planet’s health, resilience and ability to adapt.
Transitioning the Water Industry with the Circular Economy seeks to outline the key building blocks required for a utility to transition to a circular economy as well as discussing the value proposition and the many benefits to customers and the broader community, the environment and to utilities themselves.
For the Western Parkland City – the biggest and most ambitious city build project in Australian history – Sydney Water, in partnership with leading architects, engineers and urban designers, is testing an innovative new approach that integrates urban design, planning and sustainable stormwater management, with the aim of holding as much water within the urban footprint as possible.
Cooling actions such as permeable surfaces that allow for natural infiltration of water; using tanks, wetlands and green roofs for holding and treating water; and larger scale stormwater harvesting schemes built into the precinct will repurpose large volumes of rainwater and stormwater for irrigation, water in the landscape or agricultural uses.
An abundance of street trees will create a natural canopy in the Parkland City. A ‘Wianamatta street tree’, designed specifically for Western Sydney, will be passively irrigated through the street stormwater drainage system, capturing and reusing stormwater, and contributing to the health and longevity of street trees under hot, dry conditions.
Modelling of these cooling actions shows the number of extreme, very strong and strong heat-stress days per summer decreases dramatically from 47 to 19 days. Sydney Water is also working on providing sustainable and resilient water services to the Sydney Science Park, through its collaboration on a project that aims to generate an extra 2.4 million litres of recycled water a day.
The project will service up to 20,000 people with recycled water available by mid-2022 and will provide a booming western Sydney with a secure and alternate water supply, critical to supporting Sydney’s water resources.
Meanwhile, researchers at Monash University have developed energy-passive technology that is able to deliver clean, potable water to thousands of communities, simply by using photothermal materials and the power of the sun.
Led by Professor Xiwang Zhang from the university’s Department of Chemical Engineering, researchers have developed a robust solar steam generation system that achieves efficient and continuous clean water production from salty water. Through precise control of the salt crystallisation only at the edge of the evaporation disc, this novel design also can harvest the salts.
The feasibility and durability of the design have been validated using seawater from Lacepede Bay in South Australia. The technology presents a promising solution to water shortages in regional areas where grid electricity isn’t available.
This technology also has great potential in other fields, such as industry wastewater, zero liquid discharge, sludge dewatering, mining tailings management and resource recovery. Future studies will look to extend the technology to these applications with industry support.
“Our study results advance one step further towards the practical application of solar steam generation technology, demonstrating great potential in seawater desalination, resource recovery from wastewater and zero liquid discharge,” Professor Zhang said.
“We hope this research can be the starting point for further research in energy-passive ways of providing clean and safe water to millions of people, illuminating the environmental impact of waste and recovering resources from waste.”
Shifting to a circular economy approach
The transition to a circular economy is gaining momentum, as the examples we’ve highlighted in this article demonstrate, however, moving beyond simple waste management requires not only operational changes, but also a change in mindset.
As explained in the 2020 PwC report, Taking on tomorrow: the rise of circularity in energy, utilities and resources, utility leaders striving to embrace circularity can be guided by the following six steps for a more sustainable future:
• Map your circular opportunities. Examine where your current operational footprint and direction are taking you. Assess your opportunities to deliver circularity, looking deep inside your operations and outside to the surrounding community of suppliers, customers and stakeholders
• Be clear about your strategy and vision. Set out your circularity ambition and give it the necessary strategic underpinning, ensuring that it is widely communicated and understood by those who have to deliver it
• Plan your circular transformation route. For some companies, it may be small steps. For others, it will require the transformation of their whole business model. Either way, identify the company-specific capabilities that will enable your circular transition
• Develop circular collaborations and frameworks. Forge the relationships and alliances that you will need to develop an effective circular ecosystem. Circular ecosystems need to be part of a supportive framework within well-functioning markets and have clear rules, a dedicated infrastructure and a logistical network
• Measure, review and communicate your progress. Monitor your circularity steps with adequate management and reporting processes, and use those processes to further refine your circular strategy
• Move before your competitors, customers and regulators do. It’s better to facilitate your own circular transformation, rather than let others overtake you and find yourself playing catch-up
As governments around Australia prioritise the circular economy, it’s clear that utilities have a key role to play in closing the loop. Circularity is an ambitious journey, but the utilities that are able to integrate circular thinking into their core strategies and reconfigure their operations to optimise resources and minimise waste will find that they – and the planet – have much to gain.