Company: RTNTF
Filing Date: 2025-02-20
Form Type: 20-F
Source: 0001628280-25-006642
Chunk: 293

Company: RIO TINTO LTD
Filing Date: 2025-02-20
Form: 20-F
Chunk 293
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 as the Silva Carbon Origination Fund, a developer of high integrity Australian Carbon Credit Units (ACCUs) and I-Pulse, a developer of decarbonisation applications. I n 2023, this included an investment in Australian Integrated Carbon (AIC), a leading developer of high-quality carbon credits, which is an equity accounted unit. Given the significant investments we are making to abate our carbon emissions, we have considered the potential for asset obsolescence, with a particular focus on our Pilbara operations where we are building our own renewable assets and are prioritising investment in renewables to switch away from natural gas power generation. No material changes to useful economic lives have been identified in the current year as the assets are expected to be required for the transition (note 13). As the renewable projects progress, it is possible that such adjustments may be identified in the future. Large-scale renewable power purchase agreements (PPAs) require judgement to determine the appropriate accounting treatment and may result in a lease, a derivative or an executory contract depending on contractual terms (refer to note 21 for further information on significant judgements in lease assessment). The renewable solar and wind PPAs at Richards Bay Minerals (RBM) are accounted for on an accrual basis as energy is produced, while the renewable offtake arrangements at QIT Madagascar Minerals (QMM) and Amrun are leases. As part of the program to develop renewable energy solutions for our Queensland aluminium assets, we entered into 2 long-term renewable 2.2GW PPAs: the Upper Calliope solar farm and the Bungaban wind farm, at the end of 2023 and in 2024 respectively, to buy renewable electricity and associated green products to be generated in the future. In 2024, our New Zealand Aluminium Smelters signed long-term PPAs with electricity generators for a total of 572MW of hydro electricity. We also signed the Monte Cristo Wind PPA in the US, which will account for about 20% of Kennecott Scope 2 emissions abatement. These contracts are recorded as level 3 financial derivatives, with net unrealised losses of US$ 111million recognised in the current year (2023: US$ nil ) (note 24 (iv)). These derivatives require complex measurement over the contract’s term, with inputs such as unobservable long-term energy prices being key sources of estimation of uncertainty (note e). No adjustments to useful lives of the existing fleet have been identified to date as a result of planned mining fleet