The Hidden Gold in Human Urine: A Potential Solution to the Fertilizer Crisis
I never imagined I would find myself calculating how much human urine Spain produces each year, but here we are: with permanent residents and tourists combined, the country produces an astonishing 23,948 million liters of urine annually.
That’s millions of liters flushed down the toilet, which could play a crucial role in solving the looming fertilizer crisis.
Using Urine as Fertilizer: A Viable Alternative?
The concept of using urine as fertilizer isn’t new; it’s been explored for over fifteen years. Commercial fertilizers like the Swiss product Aurin are already on the market, and further innovations are underway, like one being developed in Spain by the ICTA-UAB.
This idea has gained traction not just in Spain, but around the world—from the United States and France to even the International Space Station. For years, the Rich Earth Institute in Vermont has been dedicated to researching the safety and effectiveness of using urine in agriculture. According to a BBC article, the recycling of urine serves two main purposes: it produces valuable fertilizers for agriculture and significantly reduces pollution.
Recent Advances in Processing
Despite the potential of urine as a resource, various challenges remain. Research from the University of Surrey has recently made strides in overcoming a significant issue: the clouding of membranes during the concentration process. This advancement could boost the feasibility of large-scale urine fertilization.
Turning Challenges into Opportunities
So, why do we still rely on fertilizers from the Gulf if there has been 15 years of research? The answer lies not in science, but in infrastructure and legislation. While Spain produces almost 24,000 million liters of urine, creating a system for collection and processing remains a monumental challenge.
To leverage this “liquid gold,” we would require a comprehensive network of toilets designed for urine separation and a national system for channeling, collecting, and processing this resource. Coupled with regulatory hurdles and concerns about contaminants like pharmaceutical waste, the path forward is complicated.
A Shift in Perspective
The rising cost of Gulf urea is making alternatives more attractive, akin to a small ‘gold mine’ just waiting to be tapped. Each adult generates about 473 liters of urine each year, highlighting the value in this resource.
However, the reality is that urine is often diluted up to 100 times in sewage systems, necessitating innovative solutions like separate toilet circuits—something that is currently rare in urban settings.
Looking to the Future
As Siddharth Gadkari, lead author of a related study published in the Journal of Environmental Chemical Engineering, pointed out, urine presents a paradox: it contains essential nutrients for agriculture, yet is largely treated as waste.
With ongoing testing and advocacy, we may see a shift in legislation in the coming years, allowing us to explore this untapped resource for the benefit of agriculture and the environment.
Image | Philippe Murray Pietsch
In Xataka | Going to the bathroom is a waste: urine is the real liquid gold and is full of valuable things