This segment addresses the unique challenges faced in cold regions, high-altitude areas, and places with significant seasonal changes. From freezing temperatures to limited water access, supply chain constraints, and infrastructure resilience, we aim to develop and exchange knowledge on sanitation solutions tailored to these conditions.
Webinar #3. Source Separation in Norway - 12 March 2026
Speaker: Professor Petter Jenssen, Norwegian University of Life Sciences (NMBU)
Webinar Summary:
Marine biologists say the Oslo Fjord is dying, and that the main cause for the eutrophication is too high nitrogen (N) input. This has initiated plans for N-removal from wastewater, centralizing the treatment to a few larger plants focused on nitrogen removal - not recycling. The most extreme plan is to collect all wastewater and send it to one large treatment system that requires 119km of piping in the sea. While this system would be particularly vulnerable to breaking or sabotage, it would also mean that previous investments in local small systems will have been lost.
We are living in a period of changes and uncertainty in terms of both climate and geopolitics. We must prepare to ensure national sovereignty and food security in the face of more intense precipitations and erratic weather patterns, as well as potential geopolitical instability. This calls for limiting our dependency on the finite fossil resources and fuel that we are using to produce fertilisers.
Nitrogen (N) and phosphorus (P) are among the most essential nutrients in food production, and are found in high amounts in human waste. Ammonia (NH3) for instance, 80% of which is used for fertiliser production, is currently one of the most important industrial chemicals worldwide - its production accounting for 2% of total world fossil energy use. Recovering N and P from human waste would allow for great cost savings, stronger food sovereignty and better preparedness.
But the common sewage systems using water to flush and transport human excreta are leaving us with a technical challenge: nitrogen removal is highly energy demanding. In places relying on coal or oil for electicity production, this means that the N-removal process releases more NOx into the air than it removes from wastewater, thus simply displacing the problem from water to the atmosphere.
There is hope, however, as according to the Finnish Environment Institute we should be able to recover up to >70% of the nitrogen from human waste within 10 to 30 years (vs. 6% today) thanks to source separation.
Indeed, the nutrients found in wastewater mostly come from human waste - 90% of N, 80-90% of P, 80% of K (potassium), and over 50% of organic matter. It is already possible to extract P (through the precipitation of struvite, an excellent slow release fertiliser, allowed in both conventional and organic agriculture in EU) and N (through Ammonia stripping), provided a high concentration of P and N. But conventional sewage systems dilute human waste, which end up constituting only 1 % of the total sewage volume in these systems, whereas the high concentrations needed for extraction are found naturally in source-separated urine and blackwater.
The potential for resource recovery from source-separated human excreta was successfully demonstrated in a recent EU project that terminated 3 years ago (https://www.sieugreen.eu). The blackwater and organic household waste from student housing were collected to produce biogas - which could then be burnt for electricity and heat. The nutrient-rich effluent from the reactor and CO2 released in the process both were funnelled to a nearby greenhouse, super-insulated with 40 cm of soap bubbles (which also shades against heat in summer, thus operating year round, and has very low energy requirement).
Such a system can be scaled up (like in Helsingborg, Sweden). It can also be used in small treatment plants, like in Harestua (Norway).
Source separation and advanced sludge treatment are the key.
They allow for circular solutions, cost savings, and better preparedness
Disclaimer: Due to a poor internet connection during the webinar, some parts of the audio may be unclear or not fully audible. Thank you for your understanding.
Webinar #2. Sanitation at -60°C: The Untold Story of ANTARCTICA - 11 December 2025
Speaker: Yannick Fagon
Kick-Off Meeting Cold climate working group - 15 May 2025
Speaker: Judith Maréchal
You can find the meeting notes here.
