In 2021, TSA commissioned the report below, which proposed more representative emissions factors for end-of-life tyres (EOLT), with the aim to better recognise and facilitate the use of tyre derived fuel (TDF) as a fossil fuel replacement. The outcome of this investigation identified the importance of accounting for the biomass content, due to the presence of natural rubber, in passenger car tyres, truck and off-the road-tyres. The results from the report proposed more accurate energy and emission factors, demonstrating that as a fossil fuel replacement TDF has a higher calorific value than coal, and that greenhouse gas emissions would be reduced by around 30% for the same energy input.

TSA identified that a potential barrier to uptake of TDF in local energy recovery markets was that the designated solid fuel factor for EOLT was not a true representation of the actual energy content and the associated greenhouse gas emissions from combustion. At the time of the report, the National Greenhouse and Energy Reporting (NGER) Scheme did not recognise tyres as a stand-alone fuel, failing to highlight one of the major incentives for EOLT reuse, namely as a means by which an energy intensive business, such as cement production, can reduce its greenhouse gas emissions.

Since commissioning the report, TSA has worked closely with the Federal Government to propose a 2022 update to the NGER scheme legislation, specifically to create 2 new fuel types for EOLT, allowing NGER reports to reflect emissions more accurately from TDF combustion. The TSA report became a key supporting document to assist the consultation process. These proposed amendments were generally supported by public submissions, and the changes in legislation came into force on 1st July 2022.

The new designated energy content factor and CO2 emission factors have now been updated to 32 GJ/t and 62.8 kgCO2-e/GJ respectively for passenger car tyres and 27.1 GJ/t and 55.9 kgCO2-e/GJ respectively for truck and off-the-road tyres. The updated amendments can be found here.

Download the full report here:

Australian National Greenhouse Accounts and End-Of-Life Tyre Combustion Emission Factor

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Frequently Asked Questions:

Q: What is Tyre Derived Fuel (TDF)?

A: TDF is produced from tyres through shredding, generally to a range of around 50 – 150 mm.

Q: How is TDF used in combustion?

A: Tyres can then be added as a solid fuel to replace fossils fuels, for combustion in cement kilns, boilers, furnaces, and pulp and paper mills if the appropriate processing and feed systems are in place. Since conducted this emission factors research, TSA has supported tyre recyclers and the cement industry by providing additional technical information about EOLT, to support TDF use in Australian cement kilns.

Q: Where is TDF used?

A: The use of TDF as a solid fuel in cement kilns is a relatively common practice internationally and has occurred in Australia in the past, however at the time of this report, no Australian kilns or mills were utilising TDF. A large proportion of Australia’s EOLT are currently exported, a significant percentage of which is assumed to be used as TDF in kilns around the world.