[CHALLENGE] Nutrient-Recycling-Toilet (Workshop)

Toiletten gehören zur essentiellen Hardware, die wir in Zukunft brauchen werden, um eine Lösung für Probleme wie peak-Phosphat zu finden, indem wir die Kreisläufe zwischen Landwirtschaft (Dünger) und Abwasser schließen. Ich möchte gemeinsam an einer Version ihrer Kompost-Toilette arbeiten, die öffentlich aufgestellt werden kann, z.B. auf beliebten Plätzen wie dem Mauerpark-Flohmarkt. Es müssen also Probeme wie Hygienestandards, Langlebigkeit, einfache Handhabung und Wartung, und intuitive Nutzersteuerung (damit sie die Dinger richtig benutzen) gelöst werden.

Creating an economy for the nutrient cycle is one of the most urgent and underestimated issues in the coming years. Especially peak-phosphate is a phenomenon that is as overlooked as it is pressing. Phosphate is a mineral all living things on earth need in a far greater quantity than is available in the untreated earth’s crust. This means that we need to either recycle it or, as it is currently and very unsustainably done, add it artificially from mining sources that deplete rapidly and are located in unstable or dictatorial countries, most of it in China.
During the OSCE Days 2015 in Berlin, we want to work on the challenges we face on the way to an open source prototype for a public nutrient-recycling toilet. Feel free to join and share your ideas!

Mapping the scene:

  1. What is peak-phosphate?
  2. Which solutions are there?
  3. Who is already working on them? (non-water sanitation, EcoToi, Goldeimer, Separett…)
  4. Which business models are already out there for recycling nutrients (that is Eco-Toilets: dry toilets, humus toilets, compost toilets, separation toilets)?
    Building the prototype
  5. Which technical challenges are there?
  6. Which logistic challenges are there?
  7. Which legal requirements are there?
  8. How can we build a public eco-toilet, that is educational as well as practical, wheelchair-accessible, hygenic and resistant to misuse and vandalism?

Possible Outcomes

  1. Nutrient-Recycling-Toilets for Mauerpark
    As a practical outcome of this workshop we want to design a prototype public toilet for the well known and much used Mauerpark. We chose this location for the open source prototype because
  • there is an urgent need for toilets there
  • it gives the opportunity to address an audience of international tourists as well as locals
  • there is a community garden project already working in Mauerpark, so we have a partner in the local initiative ‘Transition Town Pankow’ that is recognized by the authorities and established in the area
  1. Design an indoor public toilet for the Baumhaus-Project (http://baumhausberlin.de). Why? Because
  • this project wants to implement a zero-waste policy as far as possible
  • it will enter it’s building phase this summer, including installing new toilets for visitors
  • it can serve as an example for other similar places that serve as a venue for workshops, meetings, projects and public events, including the problem of catering+ toilets= very restrictive hygiene standards


Thursday, 11th of June - This day takes place @ The Baumhaus, Gerichtsstrasse 23
11h first get together (with coffee/ breakfast), looking at the Baumhaus facitlities
11:30h Preview of ‘Undune’ (Film by Dennis Raetzel)
13:00 -14h Introduction the problem of Peak-Phosphate by Anders Ettinger (Heschel Centre for Sustainability, Tel Aviv), Discussion

Friday, 12th of June - workshop day 1 @ Agora
11 -13h What do we need to know? formulating questions and tasks. Mapping the challenges for Himmelbeet/ Mauergarten/ Prizessinnengarten and Baumhaus.
14 -15:30h Research& Discussion: types, models, solutions. Pro&contra
17h excursion to EcoToi Toilet storage site in Marienfelde (leaving punctually, 1hour travel time to Diedersdorfer Weg 5, no OSCEdays-ticket necessary for those who only attend this part).

Saturday, 13th of June - workshop day 2 @ Agora
12 -14h (and on demand 15-16:30h) research on legal frameworks, formulating questions and demands for Berlin City administration (Grünberlin, Hygieneamt)

Sunday, 14th of June - workshop day 3 @ Agora
12 -14h (and on demand 15-16:30h) ideating, planning next steps, drafting building plans, forming working groups for continued work after OSCEdays

Monday, 15th of June - workshop day 4 (excursion: having a look at the real thing)
11 -13h trip to VivaVerde to look at the toilets they have on display and have a talk with Conrad Thimm (agricultural economist). Max. 5-7 people, please sign up with @transitionmaike .

Main coordinator:
@transitionmaike, www.ttpankow.wordpress.com / www.maikemajewski.de

planning the Berlin event
contacting potential experts and partners
developing a structure for the open source documentation
writing the documentation and encouraging others to participate
social media

PAD: To allow participants to document this challenge in real-time, a collaborative Etherpad document has been set up here:
FOLDER: To store and share documents, photos and other files relating to this challenge, please upload them to this challenge’s cloud folder:

Partners and partner organisations (so far):

Please post your comments, remarks, ideas as replies below - then I will add them and edit this post accordingly.

Resulting Projects

1 Like

THis is a really usefull project,

I regularly work for huge festivals of up to 1000 personns where we have to build DIY toilets, and i also tried to design a worm-composting toilet prototype.

I would love to get the results of you workshop to include this in the open-methodology I am working on about organizing zero waste events and working space.

How can I help you?

I will come to Berlin in late July and I would love to meet you

contact me on antoine@futureofwaste.org

For preparation read: http://holon.se/folke/projects/vatpark/Septoa_en.shtml

Yes, I wonder about applications in our challenge for South Africa:

There is a huge toilet problem in the large township in Cape Town but there is also cultural barriers of using separating toilets. My good friend, local water engineer Richard Holden has designed a composting toilet many years ago:


but in spite of how much he tried, he could not convince people to use it. He has tried for a very long time so is very familiar with the social perception challenge that one practically encounters when trying to sell the idea to the public.

My approach is to include the people I want to convince into the planning and building process here. In the workshop these are of course people who are already active in the community and eco-oriented, but their communities are not homogenous, so the toilet they design for their place will reach out to more people.
The idea is, to let it grow slowly, particularly in public places, until it becomes a normal sight. This would be a good way for Berlin, probably not so good elsewhere with more urgent hygiene problems. But you certainly have to always work with the people.
I wonder what it is that keeps them from using these toilets? Do they look different from ‘normal’ toilets (e.g. having a toilet bowl instead of a squat toilet) or require people to develop new habits (e.g. men sitting down to pee)? Maybe the place is not good and people don’t feel comfortable going there? There can be so many reasons. I guess, you will only find out by asking the people themselves. In Berlin we have http://www.nonwatersanitation.org/english/ working on this. We cooperate with the company they run for the German market: Ecotoiletten.de

I think one of the main reasons is perception. There is a feeling that they are getting “second hand” or “inferior” toilets. They have a perception of what kind of toilet makes an acceptable one. I’ll speak to Richard and see what the exact reasons were. He would actually be a great person to work with as he has many years designing and trying to promote these.

There are two other approaches I have seen used. 1) separate the Separate pee and poo in a nice molded plastic container . Community members can make business out of collecting them and placing pee in a big tank and poo in a separate big tank where their nutrients can be reclaimed. 2) everything goes to a big biodigester where kitchen waste is also mixed in and the methane is captured while the rest of the sludge is piped to a field growing fruit trees.

Perception is one of the key to promoting the toilets. This is why design becomes essential. We have to make sure that the prototype is not only as practical and free of smell as possible, but also allows for adaptation to local aesthetical habits. If people here are used to push a button to flush, we might want to add a button that will release the woodchips into the collection chamber… in other places people may find the squat toilet more hygienic than a toilet seat, there should be a way to modify the cabin. Thta’s why we start with open sourcing the information on different types of non-water toilets first before we actually build one. We also want to create open information on hygiene and materials used for the different components. And we want to explore how running a nutrient-recycling public toilet system could become a new business model for the future.
A lot of plans for such a short time, but this is only the beginning of two or more pilot case studies over the course of the coming year.
I would love to get in touch with Richard and hear more about your own experience. We’re currently thinking about how to best document our progress and allow input from other cities. I hope I will ge this set up by thursday.

Great! Maybe we can chat on weekend challenges? June 13 and 14.

I am organizing a series of talks for OSCE Days that you can see at the live stream page and I posted instructions for the speakers on what they need to do to participate on a Google Hangout on Air. We can basically do the same on June 13, 14 for a short discussion/collaboration.

I also worked a few months ago with an open source design team that created a low cost protection tent design for people in affected regions of Ebola. We gave the design to USAID and CDC at the end of our collaborative design work:



ON the highlight page, you’ll see there was a group designing toilets. These are a huge problem in West Africa.


PAD: https://pad.oscedays.org/p/berlin_nutrient-recycling-toilet
FOLDER: http://is.gd/nutrientrecyclingtoilet

Hi Antoine,
you asked how you can help. Maybe you ahve interesting links for our reading list? Do you have pictures of the toilets you have designed / tried to design? Can you explain why you chose a specific toilet type for the festivals? Can you tell us about your experiences with the worm-coposting? Any piece of information would be well appreciated.
I hope we can meet when you come,

I started the documentation, please add your own impressions and information.

Please note that the pictures and documents uploaded are only for internal use and have no confirmed open source licence (this may change later once we had the time to get the author’s approvals).

Hi, I’m here with the live call but it seems as if you’re busy on your side?
Maybe we can try again tomorrow. The Sunday workshop session in Berlin takes place from 12 -14h so I’ll be free after that. You can also try to catch me on skype.

We have uploaded a lot of pictures from our offline documentation as well as texts to read. In the pad you can find the online-documentation of what we did during the workshop, including the links to interesting people, projects and informative websites. This is still under work and open to anyone from the OSCE-community to add tips, questions and information. In the end it will be turned into a wiki in this forum to use while we build the prototypes in to coming months.

Hello @transitionmaike I’m sorry I didn’t get your answer untill now.

I could build the worm composting toilets because of lack of time but I can find back the design I did.
I also co organize a lot of events and most of the time we have difficulties to deal with the amount of feces, so I’m trying what is the best way to deal with it.

As far as worm composting is concerned I got some good skills and I’m working with designers and experts to create an open source a Big Quantities Worm Composters that would be in display for the COP21. I already built one that could cope with 2-3 kilos daily. It works very well

I participated to the OSCE days in France and I work on a daily basis on Circular economy and Open source with Future Of Waste which is a programme to help social innovators working with waste issues .

I’ll be in Berlin to organize a Sensecamp from the 21st of July until the 28 th https://vimeo.com/125124495 and I would love to meet you and see if our global community can help you in some ways. Maybe we could work on your prototype

How can I access your pad ? I couldn’t find the link



I work for Future

I would love to get your (and the communitie’s) help with the prototyping. I’m no expert in toilets myself, only good in starting projects and making them happen.

I’ll be back on July 24th, let’s try to meet up and I’ll let the others know so they can join us.


The workshop follow-up in the Forum will pause for the summer and resume in September. Messages will be read but replies may take some time.

Follow up of the workshop:

  • Baumhaus toilet will most likely not happen until later this year or early next year.
  • Mauergarten toilet is still being discussed at the community garden.

NEW: as a direct result of the workshop we are now participating in an art happening (re-enacting ‘fluids’ by Allan Kaprow) in cooperation with Antje Majewski and the Nationalgallerie. We will contribute a mobile Terra Preta toilet which we named pop-up Cyceloo, especially designed to be set up quickly for short events, packageable and light-weight enough to be transported by public transport or carrier bike.

Guckt mal hier was wir in 2013 organisiert haben: http://www.gcsm.eu/gcsm_award.html

"Blue Responsibility Award: Manufacturing for a Sustainable Terra Preta Sanitation System: With around 40% of the world’s population currently lacking basic sanitation, the need for sustainable solutions is urgent. In order to demonstrate the broad range of applications of sustainable manufacturing, the organizers of the 13th Global Conference on Sustainable Manufacturing (GCSM) launched an international competition for sustainable sanitation system design. The GCSM 2014 “Blue Responsibility Award: Manufacturing for a Sustainable Terra Preta Sanitation System” intended to stimulate the development of new sustainable sanitation systems that enable the reuse of human excreta. The objective of the competition was to design a sanitation system that creates the maximum value from what is today considered as waste. "

Hope it helps.


Thanks for the link, this is very helpful (so easy not to find things on the worldsize web). We’ll try to get in touch with them. Would you like to join the challenge for 2016? [CHALLENGE] Circular Sanitation