Zinc: Emissions
Why the smelter's power source sets zinc's footprint
Why the smelter's power source sets zinc's footprint 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 3.50 t CO2e per t range 1-6 (renewable-powered to coal-powered smelting) · cradle-to-gate, global average primary zinc Global emissions per year 48.0 Mt CO2e per year 2025 · 3.5 t CO2e/t x 13.8 Mt refined zincPer t of Special High Grade zinc, cradle-to-gate. Intensity: International Zinc Association LCA (2021 update, published 2022). Global total: Derived from IZA and ILZSG via USGS.
Share of footprint by lifecycle phase
Extraction 30% Refining / processing 65% Movement 5%Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | about 1.0 t CO2e/t (mining and concentration) | 30% | underground mining power and diesel, grinding and flotation | Ore grades and mine depth drive energy use | Share indicative |
| Refining / processing | about 2.3 t CO2e/t (roasting, leaching, electrowinning) | 65% | electrowinning uses about 3,000-3,300 kWh per t of zinc | Grid mix is decisive: Chinese and Indian coal-based smelters sit well above average | Share and power use indicative |
| Movement | about 0.2 t CO2e/t | 5% | shipping concentrate (about 2 t of concentrate per t of zinc) | Peru and Australia to China and Korea are long voyages | Indicative |
| Usage | none directly; enabling | – | no emissions in use | Galvanising extends steel life by decades, avoiding replacement steel emissions | IZA (qualitative) |
| Recycling / end of life | recycled zinc from EAF dust and galvanising residues has a lower footprint than primary (no figure published in the sources used) | – | Waelz kilns for EAF dust; remelting of brass and die-cast scrap | EU end-of-life recycling input rate 34% | EU CRM 2023; USGS MCS 2026 |
Other environmental impacts
Jarosite and goethite leach residues contain heavy metals and need secure storage. Smelters also recover cadmium, germanium and indium, which must be controlled. Mining with lead raises lead exposure risks near mines.
Levers to cut emissions
- Renewable power for electrowinning, the largest source
- Low-carbon branded zinc: Hindustan Zinc's EcoZen is reported below 1 t CO2e per t (HZL, 2024, indicative)
- Battery-electric underground mining fleets
- More recovery of zinc from EAF dust and galvanising residues
India
Hindustan Zinc's smelters in Rajasthan rely mostly on captive coal power, but it is shifting to renewable power purchase agreements; its low-carbon EcoZen brand is reported at under 1 t CO2e/t, against a 3.5 t global average (HZL 2024, indicative; IZA).
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.