Tellurium: Emissions
How copper sludge shapes tellurium's carbon estimate
How copper sludge shapes tellurium's carbon estimate 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 20.0 t CO2e per t range about 5-100; not published for current production · cradle-to-gate, economic allocation within copper anode-slime treatment. Derived by analogy with slime-route selenium (Aurubis 13.1-24.6 t CO2e/t in 2023-2025); tellurium sells for about 5 times selenium, so economic allocation could put it higher. Order of magnitude only Global emissions per year 0.02 Mt CO2e per year 2025 · about 20 t CO2e/t x 1,000 t (derived, indicative)Per t of refined tellurium (99.99%), cradle-to-gate. Intensity: Derived from Aurubis EFD Selenium 2025 and USGS MCS 2026 prices (indicative). Global total: Derived from USGS MCS 2026.
Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | small allocated share of copper mining | – | diesel haulage and grinding at copper mines | Allocation leaves almost all mining burden with copper; about 900 t of copper ore holds 1 lb of tellurium | USGS Circular 1365 (2010) (qualitative) |
| Refining / processing | dominant: slime leaching or roasting, copper telluride precipitation, electrowinning and purification to 4N-5N | – | reagents (acid, caustic), electricity, fuel for roasting | Mass allocation gives far lower values than economic allocation (Paschalidou et al. 2023); higher slime grade and recovery cut impacts | Paschalidou, Awuah-Offei & Moats 2023 (SME) and 2026 (Sustainability) (qualitative) |
| Movement | negligible per tonne | – | containers of copper telluride and refined metal; some air freight of high-purity lots | Not material against refining | Qualitative |
| Usage | no direct emissions; CdTe modules generate power at about 8-16 g CO2e/kWh over their life | – | solar generation displacing grid power | Enabling effect: against an Indian grid near 0.7 t CO2/MWh, 1 GW of CdTe (about 70-90 t Te) avoids roughly 1 Mt CO2 a year (derived, indicative) | Fthenakis & Leccisi 2021, Progress in Photovoltaics; CEA CO2 Baseline Database (indicative) |
| Recycling / end of life | low today: EU end-of-life recycling input rate about 1% | – | CdTe module take-back and semiconductor recovery | First Solar recycles modules and reports recovering up to about 90% of semiconductor material for reuse (company, indicative); volumes are small because panels are young | EU CRM 2023; USGS MCS 2026; First Solar (indicative) |
Other environmental impacts
Shares the SO2 and arsenic hazards of copper smelting. CdTe contains cadmium, so module end of life needs controlled recycling or disposal.
Levers to cut emissions
- Raise slime recovery from about 55% toward 80%, which cuts burden per tonne and adds supply without mining
- Low-carbon electricity at refineries and purification plants
- Closed-loop CdTe module recycling as the first large wave of panels retires after 2035
- Install slime circuits at refineries that now discard tellurium, as Kennecott did in 2022
India
India reports no meaningful refined tellurium output (Hindustan Copper's Ghatsila plant made none in 2019-20, IBM) and imports small amounts. Its larger link is through CdTe solar: each GW installed on India's coal-heavy grid avoids far more CO2 than the tellurium embodies.
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.