Human waste biochar could solve fertiliser shortages
Human waste-derived biochar could solve fertiliser shortages and cut pollution, a study finds.
Why it matters
- Solves global fertilizer shortages.
- Reduces agricultural pollution and energy use.
- Acts as a carbon sink by sequestering carbon.
By the numbers
- Could provide 7% of global phosphorus needs annually.
- With urine nutrients: 15% phosphorus, 17% nitrogen, 25% potassium.
- Reduces solid waste volume by up to 90%.
The big picture
- Promotes circular economy via nutrient recycling.
- Lowers dependence on imported fertilizers, aiding food security.
- Addresses climate migration by improving agricultural resilience.
What they're saying
- Doubts over charcoal's fertilizing capability due to its carbon content.
- Worries about PFAS and other contaminants in human waste.
- Questions on whether energy costs outweigh benefits.
Caveats
- High energy requirements for biochar production.
- Contamination risks remain despite source separation.
What’s next
- Need for further studies on energy efficiency and contamination management.