Conversation with Cornell Professor Dr. Rebecca Nelson

Ur-ine our thoughts, circular pee-conomy…

Pee-cycling is a part of what the Soil Factory Network and Cornell professor Dr. Rebecca Nelson refer to as the “circular bionutrient economy”, which promises an old but bold solution to closing the loop between the production and disposal of key nutrients like nitrogen and phosphorus. In simplest terms, what now harms the environment might instead save it.

If you’re like most people, you probably don’t think a lot about pee and poop, but it’s difficult to un-see that 80% of wastewater resulting from human activities goes into aquatic ecosystems untreated. The status quo produces major upstream and (literally) downstream issues, of which relatively few people may be aware because the current system is designed to divert waste from our attention rather than reclaim the nutrient-rich resources as a solution to multiple problems. The pollution of water bodies is downstream of our own bodies. Waterways are almost ubiquitously polluted with nutrient-rich sewage and fertilizer runoff that cause algae blooms and harm aquatic life (and ultimately, human life).

Whether from golf courses or agriculture, fertilizer production and application contributes further to this issue. Upstream of fertilizer production is an energy intensive process that emits greenhouse gasses. In the case of phosphorus fertilizer production, a finite resource is being mined. As for nitrogen, petrochemicals are being used to extract nitrogen out of the air, which is hardly a recipe for a balanced atmosphere and a stable climate. Downstream of fertilizer production, we also see nutrients from agricultural operations and golf courses runoff into waterways.

As a civilization, it may be time to unlearn this status quo, and return to what has been done successfully by nature for 4.6 billion years – designing out waste and “closing the loop” so that one system’s by-products become another system’s food or fuel.

How might golf address this, and how might it address this profitably? Golf can redesign itself in its embedded context of resort and residential areas that have a number of needs, including providing affordable recreation, facilitating ecosystem services, feeding turf grass, and maintaining habitable communities.

Enter pee-cycling as a solution. As the graphic shows below, urine comprises just 1% of wastewater by volume and yet contains over 80% of its nitrogen content (and hence, reclaimable resources). When urine gets mixed in with run-off from roadways, industrial waste and other effluent – as the “convenience” of the current system allows – its nitrogen and phosphorus content becomes less reclaimable and more likely to cause issues downstream. So, these nutrients pollute aquatic ecosystems instead of providing a cheaper path to feeding plants in need of nutrients (i.e., turf grass systems).

The following conversation, along with its companion article explains why “pee is for plants”.

Golf can continue the age-old alchemical quest to make gold from waste – in this case, reclaiming a liquid gold that provides a cheaper and more natural alternative that can save a golf facility money while addressing and bringing awareness to multiple ecological threats.

First, could you introduce yourself?

I’m a professor at Cornell, and I’ve been shifting from what I was doing for the last 25 years – I was running the maize genetics lab at Cornell, I was serving as the scientific director for an international crop research program, and teaching international ag. I’m transitioning now into this field of the circular bionutrient economy, and I want to be a part of a coalition of people unleashing creativity.

The Soil Factory Network is thinking of how to take currently underutilized organic resources and then bring them back into soil. One of the slogans that I’m going for is “pee is for plants”. 

In terms of scaling the pee-cycling solution, do you think that visibility is one of the most important aspects to overcoming barriers? What are the main barriers to scaling this? Technological? Social (e.g., the “ick” factor)? Are there legal or other barriers?

I think it’s an “all of the above”. You have to think about the system and entire value chain. You can go for more awareness or less awareness. There’s a way to make it invisible, but I think it’s better to use this as a tool for education. You can make it aesthetically pleasing and also show people a solution that connects them with the environment – show them how one’s body is a part of the environment.

Modern agriculture and modern sanitation are two of humanity’s blockbuster innovations. Some graphs show the tripling of cereal yield during my lifetime, but both revolutions are coming home to roost as catastrophic for the environment in many ways.  It’s time for some new innovation to reconnect these two problems into new solutions.

Based on my understanding of the status quo waste and nutrient system, there are two major issues: one upstream and one downstream of production (fertilizer production upstream and water pollution downstream). What are some of the main opportunities or challenges that a circular “pee-conomy” could address?

Phosphorus is mined usually, and it’s running out. It’s understood that this is a finite resource, and it also takes energy to extract. Then with nitrogen, we use the Haber-Bosch process – essentially, we use petrochemicals to fix nitrogen, so it’s very energy-intensive.

One of the main benefits of a circular bio-nutrient economy is greenhouse gas reduction. There are also opportunities to create compost or soil amendments with carbon-rich materials like woodchips, biochar, etc.  We take carbon that comes through our bodies and might go into the atmosphere and put it into soil.  Soil carbon is key to soil health.

And what’s the opportunity for what you might call a “base of the pyramid” innovation? Can the so-called “developed world” create innovations that work not only in the context of a golf course or more affluent community but also in somewhere like sub-saharan Africa?

I’m part of a team, led by Cornell architects, that is learning to make building materials out of waste products bound together by fungi.  We work with artists in Ithaca and elsewhere to look differently at pee and poop.  For example, artists and artisans are creating EcoLus (port-a-potties and urinals) that separate pee and poop for upcycling, delight users while educating them the impacts of how excreta are managed. A collaborator based out of Kenya is using insect larvae to turn food waste (pre- and post-consumption) into animal feed.  We’re scheming about pee-cycling events at marathon events in both Kenya and the USA. We are excited that sports and the arts can help us celebrate the ways our bodies connect with the broader environment.

Is the status quo system mainly an issue of “out of sight, out of mind”? Are people aware of the upstream and downstream impacts?

Yes, I think that’s right.  Building a new reality involves various puzzle pieces.  One is the Swedish toilet-maker Separett. You’re another – linking in high-end sporting events. We need artists and architects to design systems that are functional and aesthetically pleasing while bringing awareness. One of the issues is also regulatory, and when you’re making a profound change, there isn’t necessarily a regulatory framework in place that’s apparent or clear. I really appreciate the regulators who work with us to make a new reality that’s more sustainable and also safe.

Regarding partnership opportunities, I never would have considered the golf industry as a contender, and yet here you are! That’s really exciting.

In a recent podcast, you mentioned SDG 6 - Clean Water and Sanitation. One of our overall goals through consulting work with municipal golf courses is to celebrate golf as a vehicle for addressing sustainable development goals. What overall challenges and specifically sustainable development goals might pee-cycling address?

Going back to your question about opportunities, I think of it in a “One Health” framework in which many issues are connected. 80% of the world’s excreta goes into the environment untreated. That’s a disaster for aquatic health. Fewer than a billion people lack clean water, but twice as many lack sanitation. That’s a huge problem for human health, because the potential for disease is huge when sanitation systems are inadequate and people don’t have clean water. The current system doesn’t maintain soil health, which is a problem for the health of the crop plants that we rely on for food.  There’s planetary health with greenhouse gasses emitted by the current system.

Getting the menu of possibilities on the radar of the golf industry is something that excites me. It’s a conservative sport, so if this saves money and proves to be a better solution then that’s why it becomes more widely adopted, not because it’s “a solution for poor people” but because this is just the way to go.

And a lot of conservatives drive Tesla vehicles now! The model there is to make a better sport vehicle that happens to be sustainable. People conflate sustainability with lower quality, and so the opportunity remains in many industries, including golf – make better products that happen to be a “sustainable” alternative.

That’s why I love Separett! The Swedish company makes a range of attractive and practical designs that are used in Scandinavia and around the world. There are other processes and inventions, of course. One system capitalized by Bill Gates showed him drinking water on television. There are ways to create solid fertilizers and reclaim the water.

I’m more interested in solutions for poor people than rich people, but the rich people are important for adopting solutions to show everyone that this is a good solution. Golf could be a great solution for that because it’s such a premium and upscale audience. Meanwhile, a golf course is also a very natural looking, green, and beautiful place that can push forward this idea that “pee” is for plants!