Greenpee’s ‘liquid gold’ – closed



In 2018, the City installed four GreenPees around the Rembrandtplein nightlife area: urinals disguised as plant containers. The urinal part on the side of the container can be closed off and is only opened up on Friday and Saturday evenings. The urine is collected in a container filled with hemp fibre, which prevents odour and is then composted. Urine is rich in phosphates; mixed with the mineral-rich hemp it makes an excellent sustainable alternative to artificial fertiliser. At the moment, 250 litres of urine are collected each weekend. The hemp is then taken to a composting plant in Zwijndrecht, near Rotterdam, because there’s nowhere to process it nearby.

A lot of people are using the GreenPee urinals, but at the same time, the facilities aren’t completely solving the problem of people urinating in the streets (people even do that right next to the GreenPees). With a good circular process in place, it will be easier to offer GreenPee as a service in the city, not just as a measure to prevent public urination.


The Challenge:

Find a solution to use collected urine in the local circular economy



  • The circular process should be local, involving as little transportation as possible.
  • The urine can also be collected without using hemp fibre.
  • The quality of the solution is demonstrable – this might mean taking measurements, for example, or running trials.
  • The solution must comply with existing regulations.


Issued by: Ruimte en Duurzaamheid, Stadsdeel Centrum