Indonesia’s bauxite, alumina and aluminium sectors are growing, but there are gaps between mining, refining and smelting. 

The United States Geological Survey data of 2026 shows Indonesia’s alumina production at about 1.2 million tonnes in 2024, rising to 1.5 million tonnes in 2025. Bauxite production is estimated at 9.9 million tonnes in 2024 and 10 million tonnes in 2025. Bauxite reserves are about 2.9 billion tonnes.

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At the same time, planned capacity expansion is much larger. Alumina capacity could increase from about 9 million tonnes to 29.8 million tonnes, while aluminium production could rise from 1.13 million tonnes to 14.9 million tonnes if all projects are completed.

This creates a gap between resource supply and future demand. The planned expansion would require about 94 million tonnes of bauxite each year, compared to the current refinery demand of about 36 million tonnes. This suggests that mining output and reserves may come under pressure if all projects move forward.

Also read: Inalum flags oversupply risks, urges Indonesia to halt aluminium expansion ventures

Market trends show a similar pattern. Faster growth in supply, especially in the nickel sector earlier, led to lower prices. A similar situation may emerge in aluminium if capacity expands faster than demand.

Indonesia is en route to building a full value chain, from bauxite mining to alumina refining and aluminium production, through export restrictions and downstream policies. This has attracted investment, but also created imbalances. Bauxite production and project approvals have moved faster than refining capacity, leading to excess supply, lower prices and stockpiling in the domestic market.

At the same time, refining and smelting face their own challenges. Aluminium production depends heavily on energy. In Indonesia, coal remains the main power source. While it supports production, it also increases costs over time due to carbon concerns. This may affect competitiveness, especially as global markets shift towards low-carbon materials.

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Growth in aluminium has also been slower compared to nickel. While alumina refining capacity increased by about 4.1 million tonnes between 2014 and 2024, aluminium smelting rose by only about 0.3 million tonnes. This shows that downstream development is still uneven.

Indonesia’s mineral sector is in a transition phase. Expansion in mining and planned capacity is strong, but coordination between resources, processing and energy remains a challenge. If production grows faster than reserves and infrastructure, it could create long-term supply risks and affect the country’s position in global metal markets.

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Inalum has asked the government to pause approvals for new alumina refineries and aluminium smelters. The company said that too many projects could increase supply and reduce prices. It also warned that aluminium could follow the same path as nickel, where rapid expansion led to a fall in prices.