Written by Fedde Jorritsma from LocalWise
Human excrement contains heaps of nutrients which can be used to fertilize land and close the nutrient-loop. Ecological toilets make it possible to capture these excrements in a way that make it possible for them to be used as fertilisers. There are many ways to achieve this, such as: constructed wetlands, bio-digesters, composting toilets and urine diverting toilets. Each technology has its advantages and disadvantages. LocalWise specialises in urine diverting toilets which are relatively easy to install and can be applied in your backyard, even in the city.
The diversion of urine has many advantages:
Urine is sterile, while faeces contains many pathogens;
Odours can easily be prevented with a separated small dry faction (poo) and large wet faction (urine);
Urine contains the vast majority of the nutrients we excrete (particularly nitrogen) and is therefore a good fertiliser.
Before the urine can be used as fertilizer or compost-enhancer it needs to be kept for a month in warm climates and 6 months in cold climates.
The feces is collected in a separate container and covered with saw dust, ash, or other dry organic material. As a result, there is no smell. Poo contains many pathogens which can make us ill. It can be rendered suitable as fertilizer by:
Composting – temperatures should be 50 degrees Celsius or greater for at least a week.
Drying – the faeces should stay for two years in a dry, well-ventilated place.
After 7 years applying this technology in 'developing countries' Fedde Jorritsma (founder of LocalWise) realized how inefficient the 'western' sewage system is. We spill 30% of drinking water in the toilet and the costs of sewage systems are enormous. Moreover, the sludge is being treated and polluted in such way that it needs to be treated as chemical waste. New innovations make it possible to recover part of the nutrients, but we should ask ourselves how efficient such a system is.
In the last 2 years LocalWise started to apply the technology in community gardens and other off-grid locations like festivals and camp sites in the Netherlands. Especially festivals are interesting to rise awareness about the sanitation problem. Visitors start to realize that we are all part of an ecosystem.
You can contact Fedde at firstname.lastname@example.org