Aluminium: Emissions
Why coal power makes aluminium five times dirtier
What this tab covers The greenhouse-gas footprint of the commodity at a global level, split by lifecycle phase: extraction (or farming), refining and processing, movement, usage, and recycling or end of life. Intensities are per unit of product; the global total combines intensity with world output. Also covers other environmental impacts and the main levers to cut emissions. Emission intensity 14.8 t CO2e per t range about 4 (hydro) to about 20 (coal power) · cradle-to-gate, global average of reporting and estimated plants Global emissions per year 1,116 Mt CO2e per year 2023 · whole sector including recycling and semis; primary plus recycled average 10.04 t CO2e/tPer t of primary aluminium ingot, cradle-to-gate (bauxite mining to casting). Intensity: International Aluminium Institute, 2023 data (published Dec 2024). Global total: International Aluminium Institute, Dec 2024.
Share of footprint by lifecycle phase
Extraction 1% Refining / processing 96% Movement 3%Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | about 0.1 t CO2e/t of aluminium | 1% | diesel for strip mining of bauxite | About 4-5 t of bauxite per t of metal | IAI (indicative) |
| Refining / processing | about 14.2 t CO2e/t: alumina refining about 2.5-3, anodes and direct smelting about 2-2.5, smelting electricity about 8-9, casting about 0.3 | 96% | electricity for Hall-Heroult electrolysis (about 14-15 MWh/t), heat for the Bayer process, anode carbon and PFCs | Electricity is about 60% of the total; the power source sets the result | IAI life cycle inventory (indicative split) |
| Movement | about 0.4 t CO2e/t | 3% | shipping bauxite and alumina | Guinea to China bauxite is a long haul | Indicative |
| Usage | none directly; enabling | – | no emissions in use | Lighter vehicles and cans save fuel and freight emissions over their lives | this tile's lessons |
| Recycling / end of life | recycled aluminium about 0.5-0.6 t CO2e/t, about 95% lower than primary (indicative) | – | remelting uses about 5% of primary energy | EU end-of-life recycling input rate 32%; US recovered 3.6 Mt from scrap in 2025 | IAI (indicative); EU CRM 2023; USGS MCS 2026 |
Other environmental impacts
Red mud from alumina refining (about 1-1.5 t per t of alumina) is caustic and stored in large ponds. PFCs from anode effects are potent greenhouse gases. Bauxite mining clears forest in Guinea, Odisha and Brazil.
Levers to cut emissions
- Switch smelter power from coal to hydro, solar, wind or nuclear: the largest lever
- Inert anodes (ELYSIS) to remove process CO2 from electrolysis
- Electric boilers, heat pumps or mechanical vapour recompression in alumina refineries
- More recycling: the IEA sees recycled share rising from 36% in 2022 to 42% by 2030 (via BigMint)
- Reduce anode effects to cut PFCs
India
Indian smelters run mainly on captive coal power, giving about 18 t CO2e per t of aluminium against a 15.1 t global average (BigMint citing ICRA, 2022 data). Vedanta and Hindalco are adding renewable power purchases.
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.