About me

Hi! I am Will van Twuijver, a Rotterdam-based designer and part-time farmer working on regenerative design processes. This means that my work is informed by an overarching goal to design and develop systems that integrate environmental restoration and human wellbeing. In practice, my work is focused on the intersection of agroecological food production and grassroots-initiatives.

Focusing on this intersection allows me to explore alternative forms of food production and distribution that are based on solidarity principles, return to a human scale and increase awareness of the natural processes that form the basis of our food system. I have several years of involvement in grassroots initiatives that explore such alternatives, including projects that involve Community Supported Agriculture, waste food processing collectives and home-brewing.

In 2012 I graduated with a bachelor’s in interior architecture at Willem de Kooning Academy in Rotterdam, followed by a master’s in Collaborative & Industrial Design at the Aalto University, Finland in 2019. To further deepen my understanding of regenerative design, I completed multiple courses on the topic. Such as a minor study on Sustainability, a certified permaculture design course and a two-year course in biodynamic agriculture. Currently, I work as a part-time dairy farmer and cheese maker and am active as board member of Toekomstboeren.

Project Pee-Osk 2

  • General information
  • Year
  • Location
    Aalto University, Finland
  • Team
    Anabel Fischer, Jacqui German, Will van Twuijver
  • Status

“Stop eating meat, don’t go on holiday, don’t use your car, don’t buy new clothes and don’t have kids.” We all have heard these ‘solutions’ to halt climate change and we are convinced that this negative framing centred around hardship and ‘giving things up’ does not capture people’s imagination. Instead, the Pee-Osk encourages people to get familiar with sustainable solutions by highlighting what can be gained, by bringing processes back to a human scale and by making it humorous.

The Pee-Osk serving bloody maries grown on human urine

The concept

This project goes back to a necessary human function, going to the toilet, and find an comical way to cycle human waste streams. When talking about the benefits of human fertilizer for food production, we face confusion, disgust and negativity. It is time to change the perception of human waste! We developed the Pee-Osk concept to utilize the human byproducts for cultivating ingredients for Bloody Mary’s, which in turn aid in feeding the toilet. With the Pee-Osk, we want to demonstrate the fun of sustainability, simplify technological processes and challenge people’s concept of human waste products.


The design of the Pee-Osk is based on an Asian vending cart. The inner part contains a worm compost bin and five wicking beds in which the tomatoes, cucumbers and herbs are grown and can be closed in order to funciton as a green house. The outside is used as a bar and buffet, making the Pee-Osk accessible from all sides. The whole installation can be moved by one or two people

How urine is converted to plants

A combination of low-tech solutions converts urine into plants

The pee-osk is based on a combination of different ecological design elements, such as bioponics, wicking buckets and compost tea, to form an integrated system. Each element in the system was chosen for their simplicity, resiliency and low-tech application. The reasoning behind these criteria was to make the process of converting urine to fertiliser more accessible.

The sub irrigation system

To reduce the risk of contaminating plants with urine, we made use of wicking buckets to sub irrigate the plants.

Wicking buckets are water efficient design for plant pots. These buckets contain a water reservoir below the planting soil. The soil is placed on top of the reservoir and due to its capillary action can ‘wick’ the water upwards. Because the water is fed to the plants from the bottom, hardly any water evaporates. In addition, the top layer of the soil will not get too wet: reducing the chance of mold.