This project will improve Australian fuel heat release models to contribute to more consistent fire behaviour model outputs and hence fire danger ratings within the Australian Fire Danger Rating System (AFDRS) across different fuel types.
This project is currently open for Expressions of Interest.
Project teams responding to this call for Expressions of Interest (see PDF in top-right corner) are required to submit their response using the Centre’s current EOI submission form.
EOI proposals are due by 5pm AEST on 3 October 2025 to research@naturalhazards.com.au.
An online briefing took place 10 September 2025 to provide a more detailed briefing of the project and the opportunity for interested parties to pose specific questions. Watch the replay below.
Project details
This project concept was submitted by NSW Rural Fire Service.
The project aims to:
- Review existing literature
Identify Australian fuel types and key species lacking known heat of combustion values and document current state of knowledge.
- Conduct combustion experiments
a) Develop a standardised method for determining the rate and nature of heat release replicating real-word bushfire spread.
b) Investigate key fuel types (including but not exclusively wet forest, dry forest, grass, heath and pine) under varying environmental conditions e.g. varying curing and different fine fuel moisture to determine the rate and nature of heat release. This will include collecting and analysing data on moisture of extinction, fireline intensity, ignitability, total heat release, combustion efficiency and the proportion of heat released in smouldering combustion.
c) if possible, examine different strata from fuel types (e.g. surface, near-surface, elevated and canopy).
- Improve Australian fuel heat release models
Make recommendations based on outputs from the combustion experiments that can be related to field-based observations leading to direct improvements to a range of fire and land management decision-making products. By increasing the accuracy of measures of fireline intensity, this will contribute to more consistent fire behaviour model outputs and hence fire danger ratings within the Australian Fire Danger Rating System (AFDRS) across different fuel types. Furthermore, this research will have implications relating to smoke, carbon release, fire impacts and fire research focusing on fire-atmosphere interactions.
Frequently asked questions
Q) Are the word limits in the submission form a guideline?
A) Each question in the submission form has a required word limit. Submissions with statements exceeding the word limit will be deemed non-compliant.
Q) What do you mean by “Total cumulative FTE contribution over the life of the project"?
A) This means the total FTE per person over the life of the project. Maximum total FTE for each person is 1.0. Cumulative is to add up all the personnel.
For example:
- If someone is contributing 1 FTE per year for three years, then their FTE is 1.000 FTE
- If someone is contributing 0.1 FTE per year for three years, then their FTE is 0.100 FTE
- If someone is contributing 0.05 FTE for two years of a three year project, then their FTE 0.033 FTE
- If someone is contributing 0.5 for two years and 0.1 for 1 years of a three year project, then their FTE is 0.367 FTE
Q) Can the Centre connect interested parties with other agencies or organisations involved in developing this project, to discuss it further and assist in developing an EOI submission?
A) While an EOI is open for submissions, the Centre procurement processes don't allow Centre staff to connect interested parties, as this can cause conflicts of interest. However, interested parties are able to contact whomever they wish, excluding those organisations listed on the EOI, to discuss the project and explore opportunities for collaboration or potential consortium submissions. If an online project briefing has been organised for an EOI, we encourage interested parties to attend the briefing to ask questions and meet other interested parties.
Q) Can interested parties contact the Centre with questions about the project design before submitting?
A) While an EOI is open for submissions, Centre procurement processes don't allow Centre staff to share knowledge of the project design directly with interested parties. However, if you have questions, you can email research@naturalhazards.com.au and you will receive a timely response if appropriate, according to our procurement processes.
Q) Is there a preference for a project team to be from a single research organisation, or from across multiple organisations?
A) The Centre has no preference for either a single organisation or a multi-organisation project team. EOIs will be accepted from either and will be evaluated against the evaluation criteria in the same way.
Q) Can the proposed project team include researchers from government agencies or research consultancies, as well as university-based researchers?
A) EOIs will be accepted from multi-organisation project teams, and project teams can include researchers at government agencies and research consultancies. The proposed project team's capacity to undertake the project will be evaluated in the same way whether researchers are university-, consultancy- or agency-based.
Q) Would academic salaries (excluding administrative overheads) be eligible to budget?
A) Yes, academic salaries can be included within the project budget, but only when they are direct project costs and their salary is not already covered elsewhere. E.g. the salary costs of a contract researcher who is actively working on the project can be included up to the FTE component they are contributing. However, the salary costs of a tenured academic who is already paid through the university/research organisation would be included as an in-kind contribution up to the amount of their FTE contribution to the project.
Q) What do you mean by "peer review"?
A) This is a quality control process. Where requested, the final report must be reviewed by someone who is an expert in the field and independent of the project.
Q) At what rate can salary on-costs be charged?
A) Administrative overheads are limited to direct salary-related on-costs. Indirect cost recoveries are not to be included. Other administrative overheads and indirect costs can be included as in-kind contributions. Where the salary on-cost rate exceeds 28% this will need to be justified.
Q) Can equipment costs be included in the budget?
A) Ordinarily, project funds are not to be used to purchase equipment. Where funds for equipment are requested, they will need to be justified.
Q) Can international research teams apply? Alternatively, can international research teams be part of a consortium bid?
A) International research teams can be part of research projects when they are part of a consortium submission that is led by an Australian research organisation. The international team would need to be subcontracted by the lead Australian based research organisation. Please note that all budget submissions must be in Australian dollars and the lead organisation must bear the cost of funds transfer and responsibility for due diligence as required under Australian Foreign Interference regulations.
Q) Is there an option of registering my interest as an independent researcher that could assist a larger team or are you only able to consider proposals that address the entire project?
A) Yes, you can submit an EOI as an independent researcher addressing part of the project requirements. In the EOI submission form, please outline which aspects of the project you can address. Once the EOI closes, we can consider linking researchers together, although whether or not we can do that will depend on a range of factors, so we can’t guarantee that outcome. Of course, the other option is to reach out to potential collaborators now about putting in a joint EOI submission that addresses the entire project.
Q) Regarding the project aim’s reference to the “rate and nature of heat release”: do you require time-resolved heat release rate (HRR, kW), or is heat of combustion (kJ/kg) sufficient? By “nature,” what specifically should be reported (e.g., peak vs. sustained HRR, time-to-peak, or the relative contribution of flaming vs. smouldering combustion)?
In terms of replicating the rate and nature of heat release in real-world bushfire spread, which experimental scales do you expect evidence from—for example, bench-scale calorimetry, mid-scale cribs, bed burns, or limited field validation?
A) Key point – we want to be able to better understand fireline intensity. To do this, we need an idea of the heat yield (not just heat content), and the proportion of this released in flaming combustion. The duration of flaming combustion would be useful to know.
For this work, calorimetry could be useful, however it will be important to relate it to field conditions either through measurement of live fire in the field or simulated live fire (i.e. constructing realistic fuel beds inside wind-tunnels).
At present, the key input used in fireline intensity calculations is the heat of combustion, so this remains an essential output. The important thing is that the outputs can be tied back to real-world bushfire conditions.
The results need to be compatible with the smoke modelling, carbon release assessments, and fire–atmosphere interaction models that agencies currently use. This means the project should be designed in a way that allows the outputs to align with stakeholder needs. While we’re not specifying a single definition of combustion efficiency right now, we expect applicants to demonstrate how their proposed approach will be useful for operational modelling and impact assessment.
Currently, intensity calculations use total heat of combustion values, but for this project, it would be very useful to separate the heat released during flaming combustion from that released during smouldering. The total heat release is still relevant, for example in plume and convection modelling, but partitioning these components will allow us to better reflect what actually occurs in the landscape.
Our broader aim is to understand the difference between the theoretical calorimetric values and the energy that is actually realised during burning under varying conditions (e.g., hot/dry vs. cool/damp fuels). This helps us assess incomplete combustion and variations in efficiency. For us, combustion efficiency is best understood in terms of how much of the available fuel energy is released during flaming, expressed as a percentage of the theoretical maximum.
Improving these values will enhance the accuracy of downstream models—including smoke and fire –atmosphere interactions—and ensure our simulations are more representative of real-world fire behaviour.
Q) Do we also need to conduct research on liquid fuels, or should the focus remain on biomass conversion and its equivalent representation?
A) Liquid fuels are not within the scope of this project. The project aims to understand Australian vegetation fuels
The focus of this research is on biomass fuels—such as leaves, litter, sticks, and bark—rather than liquid fuels. The key consideration is understanding the difference between the theoretical energy content of these fuels, as measured in laboratory conditions, and the energy that is actually released during combustion in the landscape or in simulated landscape environments.
This includes examining the energy release profile: specifically, how much energy is released during flaming versus smouldering combustion, and how those proportions influence fire behaviour and impacts.
Q) Do you expect to get an experimental setup out of this project?
A. Yes, part of the expectation is to develop clear experimental protocols. These would allow the work to be replicated in different environments and under different conditions, ensuring that consistent and comparable results can be obtained if the methods are applied elsewhere.
Having an experimental protocol is important so that the findings can be extended to other fuel types in the future. While this project cannot feasibly cover the full range of Australian fuels, producing a robust set of guidelines for future reference will be a valuable outcome.
Q) Is there a priority for different vegetation types?
A) The Expression of Interest identified wet forest, dry forest, heath, grassland, and pine as the current top priorities. These represent high-level vegetation categories, and while the project does not delve into more detailed sub-fuel classifications, we would like the research to address these primary fuel types first.
Q) Beyond moisture content - are you also interested in other external factors that may impact heat release (eg. wind speed, fuel structure) or is there an assumption that other factors in the fire behaviour models already account for that?
A) No, we haven’t specifically highlighted wind speed in the EOI; however, we have outlined the different fuel strata and fuel structures as a key component. It would indeed be valuable to also consider additional external factors, such as wind speed, which can significantly influence heat release during fuel combustion.
Many of the widely used models are built on rate-of-spread; this project should do some testing of whether these models adequately capture effects of fire intensity. E.g. Curing level (% dead) or grass affects spread rate. But should it also affect total energy released?