PeeCycling: turning a stadium urinal into a fertiliser factory

Most of us never think about what happens after we flush. A team at the University of Cape Town thinks about it every day, because urine carries the same nutrients farmers pay good money for.

A problem hiding in plain sight

Urine is less than 1% of household wastewater by volume, yet it holds most of the nitrogen and potassium in it, and more than half of the phosphorus. Those are the building blocks of commercial fertiliser. At the same time, South Africa imports about 80% of its fertiliser, so farmers are exposed to global prices and supply shocks.

What PeeCycling does

PeeCycling is a UCT spin-out co-founded by Prof Dyllon Randall and Dr Caitlin Courtney, whose PhD research produced the heart of the process. Urine is collected separately and treated so that it doesn’t break down or smell. It is then passed through reverse osmosis, the same kind of technology used to turn seawater into drinking water. What comes out is two useful products: a liquid fertiliser and a stream of clean water, with no waste left over.

The hard part was making reverse osmosis work at all. Untreated urine quickly blocks the membranes, so the team spent years learning how to adjust its chemistry first.

Tested in front of a full stadium

In August 2026, through a partnership with the Bidvest Group, the team plumbed one urinal trough at DHL Stadium in Cape Town into their system for two big rugby matches. They collected about 2,700 litres at the first match and 3,600 litres at the second, from just one of several urinals in the bathroom. For every 1,000 litres treated, around 700 litres of water came back, ready for flushing, cleaning or irrigation.

A few weeks later, on 3 September, PeeCycling took first place at the 2026 FNF AfriGreenPitch Challenge, a pan-African competition for green-economy innovators.

“Nature knows no waste.”

Years in the making

None of this happened overnight. Back in 2018, Randall’s student Suzanne Lambert unveiled what UCT described as the world’s first bio-brick grown from human urine, set at room temperature instead of being fired in a kiln. Each experiment built on the last, until the idea was ready for a stadium.

What builders can take from this

• Look closely at what everyone throws away. Waste is often a resource in the wrong place.
• Test in the real world as early as you can. A packed stadium says more than a lab report.
• Find a partner who owns the space you need. Bidvest gave the team access to volume they couldn’t get alone.