Biochar from human waste could solve global fertiliser shortages, study finds

Excrement contains nutrients needed for crop growth and a new source of them could cut farming's huge CO2 output

Charcoal made from human waste could help solve fertiliser shortages as well as reduce pollution and energy use, a study has found.

Biochar is a form of charcoal made from organic matter treated at high heat, which is often used on farming soil as a fertiliser. The process also removes carbon from the atmosphere, making it a useful carbon sink.