B5 ResearchProject
RACEforBusiness
Research themeB5: Anaerobic digestion for electricity, transport and gas
ISBN: 978-1-922746-42-9
Industry Report
Mapping Organic Waste in Sydney: Advancing Anaerobic Co-Digestion
June 2023
Citations
Jazbec, M., Turner, A., Madden, B., and Nghiem, D.L. (2023). Mapping Organic Waste in Sydney: Advancing Anaerobic Co-Digestion Research Theme B5 Anaerobic digestion for electricity, transport and gas. Prepared for RACE for 2030 CRC
Project partners
Project team
University of Technology Sydney
• A. Turner
• M. Jazbec
• B. Madden
• D.L. Nghiem
Acknowledgements
This project is supported by funding from RACE for 2030, NSW Department of Planning and Environment, NSW Department of Primary Industries, NSW EPA, and Sydney Water. We would like to thank the Industry Reference Group participants from the following organisations: Blacktown City Council, Jemena, Penrith City Council, and Sustainability Advantage.
Although the IRG members and partners have provided valuable inputs and feedback throughout the project, the findings and recommendation included in this report do not necessarily reflect the views of each individual member.
Acknowledgement of Country
The authors of this report would like to respectfully acknowledge the Traditional Owners of the ancestral lands throughout Australia and their connection to land, sea and community. We recognise their continuing connection to the land, waters and culture and pay our respects to them, their cultures and to their Elders past, present, and emerging.
What is RACE for 2030?
RACE for 2030 CRC is a 10-year cooperative research centre with AUD350 million of resources to fund research towards a reliable, affordable, and clean energy future. https://www.racefor2030.com.au
Disclaimer
The authors have used all due care and skill to ensure the material is accurate as at the date of this report. The authors do not accept any responsibility for any loss that may arise by anyone relying upon its contents.
What is in the report?
This report brings together data from the energy, water and waste sectors to investigate the renewable energy generation potential available from diverting urban organic waste (UOW) from landfill or composting to biogas generation in existing anaerobic digesters (AD) at three of Sydney Water’s wastewater treatment plants (WWTP), Malabar, St Mary’s and Riverstone It identifies and maps the available UOW resources, estimates the greenhouse gas savings and potential benefits of the biosolids produced. It identifies and maps relevant stakeholder groups and provides an analysis framework for future work.
The report was peer reviewed by industry partners and the full details have been included in the public report.
Why is it important?
Most of the emissions from the waste sector come from solid waste disposal to landfill and the associated methane emissions, much of it from organic waste, as only a small proportion of the methane is captured and used. The other main source is emissions from wastewater treatment, which the installation of anaerobic digestors could assist with mitigating.
The energy, local government, waste and waste sectors share policy objectives relating to achieving netzero greenhouse gas emissions by 2050, commitments to the Global Methane Pledge of cutting anthropogenic methane emissions by at least 30% from 2020 levels by 2030, reducing organic waste disposal to landfill and implementing circular economy principles. In particular, in 2021 the NSW Government identified a 1.1 million tonnes per year (t/y) processing gap for food and garden organic waste in NSW when they were assessing the future infrastructure needs to meet the NSW Waste and Sustainable Materials Strategy objective. At present there is only one commercial AD plant in Sydney which accepts food organics (FO) and fats, oils and grease (FOG) and it has a capacity of 52,000 t/y. To service the demand of the Greater Sydney region alone, it was projected that 260,000 t/y of extra anaerobic digestor capacity would be required by 2030
These policy objectives could all be addressed by using UOW from residential and non-residential sources such as food and garden waste and fats, oils and grease (FOG) to generate biogas via anaerobic digestion and a digestate which recycles the nutrient content and reduce greenhouse gas emissions
What did we do ?
The project team estimated the quantities and energy content of various UOW streams within the organics value chain within the defined catchment areas for the 3 WWTP, including projections The data was summarised by local Council area, to identify the potential organic resource and current collection system, as shown in Table 1.
Co-benefits, such as nutrient recovery and greenhouse gas emissions saving, were also quantified. The data was analysed to identify hot spots and summarised to quantify the resource available in the 4 local government areas adjacent to the 3 WWTP, as summarised in Figure 1.
Figure
Projects of organic waste and bioenergy generation potential to 2030/31 were estimated for UOW from residential sources in the local government areas, due to the paucity and uncertainty of data for the non-residential sector. This is shown in Figure 2 and does not include the National Food Waste strategy target of halving FO generation by 2030, but rather reflects current trends in FO generation.
Table 1: Overview of the Council’s demographics, business activity, organic waste streams and energy potentials. 1. Summary of organic waste resources available for codigestion by sector, type and WWTP capacityWhat difference will it make?
The study identified that 20% of Sydney’s AD infrastructure capacity gap could be provided by the 3 existing WWTPs.
Understanding the availability of local bioenergy resources can contribute to achieving multiple objectives of different organisations in the energy, water and waste sectors relating to greenhouse, waste reduction and circular economy This report will assist the developing decarbonisation options for the energy, waste and wastewater sectors, and may provide a basis for consultation and consensus building with the various government organisations which regulate these interconnected systems.
What’s next?
The report identifies a range of additional research projects, including the use of the data for further analysis, further analysing the UOW stream, reviewing UOW collection methods, detailed assessment of methane and energy generation potential of the UOW feedstocks, review of options for collection and processing of UOW streams, a UOW market analysis for the Greater Sydney area, developing a business case for UOW co-digestion, improving the understanding of and engagement with stakeholders in the UOW value chain, and benchmarking international best practice.
The method could also be applied to other geographic locations, especially if there already are existing AD plants with excess capacity and a need for renewable biogas.
Figure 2. Summary of organic waste resources projections for 2030/31 by local government area
