Humans produce around 1 million tonnes of poo every day and at least 80% of it is wasted. Aargh. On a finite planet, this is yet another example of how we squander precious resources.
My son, Connor Bryant, recently highligthed the absurdity of almost every country measuring success in GDP, which essentially means that governments and business are chasing an impossible goal of infinite growth on a finite planet.
As he put it: our linear economy doesn’t just extract, it burns through materials, turns them into short-lived products, and leaves behind waste. The cycle is brutally short and brutally unsustainable.
Poo is no different. We put enormous effort into growing, processing, transporting, and cooking food. Our bodies use some of that energy to live — and then we poo. A small proportion of this is reused as fertiliser, compost, or an energy source. But the vast majority is:
- Treated and discharged — nutrients wasted.
- Landfilled or incinerated — energy and nutrients lost.
- Mismanaged — actively contaminating water and soil.
This is madness.
Human poo is packed with nitrogen, phosphorus, and potassium — exactly the nutrients we spend huge amounts of energy and money mining or manufacturing as fertilisers. Yet every day, we flush them away.
Just as Connor argues for a circular economy, we need to close the loop with poo too. We can do this by rethinking sanitation systems to:
- Capture nutrients.
- Generate renewable energy.
- Return goodness safely to the soil.
A circular approach to human waste isn’t just possible, it’s essential.
On a finite planet, wasting our poo is indefensible.
