Aluminium is a crucial element contributing to the development of modern technologies focusing on energy transition. It is also the reason behind the emission of greenhouse gases (GHGs) worldwide. The International Energy Agency (IEA) has reported that aluminium production alone contributes around 3 per cent of the GHG emissions (around 270 tonnes).

The clean energy transition will directly increase the demand for aluminium to a whopping 40 per cent by 2030. To reduce direct and indirect emissions, the decarbonisation of aluminium subsectors has become mandatory. To do so, a vivid map of the aluminium industry’s carbon footprint across the material life cycle must be designed.

A carbon footprint map of the aluminium industry

The aluminium sector can contribute considerably to achieving net zero emissions via decarbonisation efforts developed and adopted worldwide. This carbon footprint map enables us to understand where exactly things can be transformed to achieve this big goal.

The primary aluminium production process contributes to over 90 per cent of aluminium emissions even though primary aluminium amounts to >70 per cent of the global supply.

• Use of combustible fuel and electricity for mining and other purposes
• Use of fossil fuel-generated electricity for refinery processes
• Emission of steam and heat in refining processes
• Ancillary material production, such as anodes for refining and smelting
• Fossil fuel-generated electricity for electrolysis during smelting
• Direct CO2 emissions from carbon anodes during electrolysis
• Heat and steam generation due to the fabrication and casting of aluminium
• Emissions related to transportation
• Waste disposal and processing

Nearly 77 per cent of the emissions occur in the aluminium smelting process. This industry highly relies on fossil fuel-generated electricity. So, the decarbonisation of this sector is dependent on the power to be used in the smelters worldwide.

Decarbonisation challenges in the aluminium industry

Aluminium plays a significant role in creating a sustainable economy. It is needed for the construction of renewable and non-renewable technologies. It is used in the aerospace and lightweight engineering industries. Smart gadgets, lighting, and even photovoltaic cells need aluminium. This diverse need for this lightweight metal creates hurdles in decarbonisation, as the demand is always at its highest.

Aluminium is 100 per cent recyclable . However, the procurement of used aluminium end-user products needs to be better defined. This drives the requirement of producing aluminium from scratch, resulting in GHG emissions.

Significant disparities are detected in the decarbonisation process throughout the aluminium value chain globally. The players need to show coordination in using cost-competitive renewable power despite being a part of an energy-intensive sector. The transition from non-renewable to renewable energy is an expensive affair for many.

Ways to overcome challenges and decarbonise aluminium production

1. Emphasising the use of recyclabled aluminium

Recycled aluminium, used for manufacturing semi-finished products, consumes 95 per cent less energy. This is an immense factor in reducing carbon emissions.

This viable route can be boosted by promoting exclusive B2B platforms for recyclable aluminium. For instance, Alibaba, IndiaMart, and AL Biz focus on creating a marketplace where buyers of recycled aluminium can connect with top producers worldwide. Such partnerships can accelerate the decarbonisation process.

2. New technology in aluminium smelting decarbonisation

Green initiatives to reduce carbon emissions in the aluminium smelting process will help decarbonise this sector considerably. As mentioned, this sub-sector alone contributes 77 per cent of the carbon emissions. So, addressing the challenges in this sub-sector will significantly take us closer to the net zero emission deadlines.
Hydro is one of the pioneers of green aluminium. It has developed a technology to fully decarbonise aluminium smelting. This company was awarded at the UN Climate Change Conference 2024, held in the UAE, for this innovation.

The Hongqiao Group in Yunnan, China, has constructed a hydro-powered aluminium smelter and relocating its infrastructure. Many other aluminium giants in China are adopting energy transition methods to achieve the net zero emission goal.

3. Using renewable energy and near-zero electricity

Renewable energy and near-zero-emission electricity will deliver the ideal route to decarbonise the aluminium sector. Rio Tinto has collaborated with the Australian Renewable Energy Agency to check the efficiency of hydrogen as an alternative to natural gas.
Many Chinese primary aluminium manufacturing companies are switching to hydro energy to replace conventional fossil fuel-based electricity to achieve the net zero emission goal.

4. Replacing carbon anodes with inert anodes

Carbon anodes get oxidised during aluminium electrolysis and release CO2. Replacing these anodes with inert ones will considerably reduce the production of GHGs. In 2021, RUSAL, the Russian aluminium giant, used inert anodes to produce primary aluminium at a massive scale. Rio Tinto and Alcoa followed this path in the same year.

Embracing the future of decarbonisation in aluminium industry

With the aggressive reform of carbon emission regulations, every significant player in the aluminium value chain must comply. For instance, the EU has mandated all importers to follow the Carbon Border Adjustment Mechanism (CBAM). Embracing Big Data and AI technology such as CarbonChain for automation will help in carbon accounting in supply chains. Replacing fossil fuel-generated electricity, using inert anodes, and embracing other methods will contribute to this transition. As days pass, new technologies will emerge to overcome such challenges.