<div>Steelmaking value chains are economically important to Australia, but the need to decarbonize traditional steel-making processes could disrupt existing supply lines. Hydrogen-based iron and steel production offers one pathway for reducing the carbon intensity of steel. The opportunities and challenges presented by this technology, for Australia, are obscured as its cost competitiveness depends on the interaction between multiple industrial processes, including feedstock requirements, storage options, and the availability of infrastructure. To address these problems, we have developed the Green Steel Economic Fairways Mapper. This mapping tool enables user-driven assessments of the green iron or steel resource potential across Australia. The tool optimizes system capacities for renewable energy generation, battery storage, hydrogen electrolysis, and hydrogen storage to estimate the levelized costs of green steel and how these costs vary regionally. Here, we present examples of analysis and integration with other geospatial datasets. Our model compares favourably to previously published cost estimates while also providing granular, spatial considerations of resource potential. Examples demonstrate that the tool that can be used to inform decision-making in the development of actions to de-risk green steel development within Australia.</div>

<div>Steelmaking value chains are economically important to Australia, but the need to decarbonize traditional steel-making processes could disrupt existing supply lines. Hydrogen-based iron and steel production offers one pathway for reducing the carbon intensity of steel. Here, we present maps assessing the costs of hydrogen-based direct reduction of iron oxides (to produce hot briquetted iron), optionally coupled with steelmaking in an electric arc furnace (i.e. the H2-DRI-EAF value chain). Developed as part of the Exploring for the Future program and in collaboration with Monash University, these models build off the functionality of the Green Steel Economic Fairways Mapper (beta release), with additional enhancements to the modelling algorithm to reflect constant furnace operation, the incorporation of costings to transport the produced hot briquetted iron or steel to domestic ports, and the optimisation of facility capacities. The capacity of facilities (including solar and wind generation, proton exchange membrane [PEM] electolysis, battery storage, and hydrogen storage tanks) are determined by the 1 Mtpa production target and the local availability of renewable energy resources, as modelled according to 2019 data sourced from the Renewables.Ninja (https://www.renewables.ninja/; Pfenninger & Staffell, 2016; Staffell & Pfenninger, 2016). The high-resolution (approximately 5.5 km pixels) maps reflect our preferred technology cost assumptions (see Wang et al., 2023) for the year 2025. Iron concentrate feedstocks are assumed to cost AU$150 per tonne, reflecting approximate costs for 65 % Fe pellets as derived from magnetite ores. Conversions to USD assume US$1.00 = AU$0.73.</div><div><br></div><div>Geoscience Australia's Exploring for the Future program provides precompetitive information to inform decision-making by government, community and industry on the sustainable development of Australia's mineral, energy and groundwater resources. By gathering, analysing and interpreting new and existing precompetitive geoscience data and knowledge, we are building a national picture of Australia's geology and resource potential. This leads to a strong economy, resilient society and sustainable environment for the benefit of all Australians. This includes supporting Australia's transition to a low emissions economy, strong resources and agriculture sectors, and economic opportunities and social benefits for Australia's regional and remote communities. The Exploring for the Future program, which commenced in 2016, is an eight year, $225m investment by the Australian Government.</div>