Cassava: Emissions
Why land clearing dominates cassava's carbon footprint
Why land clearing dominates cassava's carbon 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 0.90 t CO2e per t range 0.9 (median) to 1.32 (mean) · cradle-to-retail global median, GWP100; land-use change dominates Global emissions per year 310 Mt CO2e per year 2024 · 0.9 t CO2e/t x 341.9 Mt; about 450 Mt at the 1.32 mean (indicative, upper estimate as land-use change is averaged in)Per t of cassava roots at retail; cradle-to-retail. Intensity: Poore & Nemecek 2018 (Science), median stage values as tabulated by Our World in Data (indicative). Global total: derived from FAOSTAT 2024 and Poore & Nemecek 2018 (indicative).
Share of footprint by lifecycle phase
Extraction 89% Movement 11%Footprint by lifecycle phase
| Phase | Intensity | Share | Main sources of emissions | Notes | Source |
|---|---|---|---|---|---|
| Extraction | about 0.8 t CO2e/t: land-use change about 0.6, farm about 0.2 | 89% | forest and bush clearing in Africa, nitrogen fertiliser in Asia | Land-use change is about two-thirds of the median. On Thai starch farms, cultivation is about 60% of starch footprint, mainly from nitrogen fertiliser. | Poore & Nemecek 2018 (Science), median stage values as tabulated by Our World in Data (indicative); Hansupalak et al. 2016 (KURDI/CIRAD) |
| Refining / processing | about 0 t CO2e/t for roots; 0.22-0.34 t CO2e per t of starch at the factory | 0% | rasping, drying, wastewater methane, fuel oil or biogas | Whole Thai starch footprint is 0.61-0.97 t CO2e per t of starch. About 90% of Thai factories switched from fuel oil to biogas from wastewater in ten years, cutting about 0.9-1.0 Mt CO2e a year. | Hansupalak et al. 2016 (KURDI/CIRAD) |
| Movement | about 0.1 t CO2e/t | 11% | trucking roots to factories; shipping chips and starch to China | Roots must be processed within days, so most haul distances are short. | Poore & Nemecek 2018 (Science), median stage values as tabulated by Our World in Data (indicative) |
| Usage | not in the cradle-to-retail total | – | boiling, frying, fermenting gari and fufu, often over firewood | Household cooking on wood in Africa can be significant but is not in global averages. | indicative |
| Recycling / end of life | not applicable as recycling | – | peels, pulp and wastewater | Pulp goes to feed; untreated wastewater ponds emit methane, which biogas capture turns into fuel. | Hansupalak et al. 2016 |
Other environmental impacts
Land clearing for cassava in Africa, soil nutrient mining, and high-strength cyanide-laden factory wastewater. Cassava needs little water and few inputs.
Levers to cut emissions
- Biogas capture at starch factories (already about 90% of Thai plants, saving 0.9-1.0 Mt CO2e a year, Hansupalak et al. 2016)
- Higher yields on existing land: Nigeria 5.8 t/ha against 35.6 t/ha in India (FAOSTAT 2024)
- Disease-free planting material against mosaic disease
- Precise nitrogen use on commercial farms
India
India's very high yields (35.6 t/ha, FAOSTAT 2024) and lack of new land clearing suggest a lower farm footprint than the global median, though no Indian LCA was found. Salem's sago units discharge starchy wastewater, and biogas capture there lags Thailand.
Emission figures are indicative global averages from the life-cycle studies named; actual footprints vary widely by site, energy mix and method.