Nitro(gen) Cold Brew Space Economics
I was recently reading Babylon’s Ashes by James S.A. Corey (part of the The Expanse series) and there was a line that jumped out at me. The series takes place in the 24th century, and most of the action happens in space. There are frequent mentions of hydroponics, and one of my favorite characters (Pax, for all the Expanse-heads out there) is an actual botanist. In my recent reading, one character off-handedly mentioned basing their currency on nitrogen. “Ok, yeah, sure. Currency based on minerals, that makes sense.” But it’s way cooler than that, so let me geek out for a moment about the basics of plant biology, guano islands, Haber-Bosch process, and some economics.
Plants need Nitrogen
Plants really really need nitrogen. It’s a major component of photosynthesis, and makes up a great deal of plant biology. Nitrogen is a major component in chlorophyll, which gives plants their green color and allows them to convert sunlight to food. When you hear about crop rotation, depleted fields, or regenerative agriculture, this often refers to the process of making sure there is enough nitrogen in the soil for crops to thrive. It’s a good thing that our atmosphere is about 80% nitrogen, but most of that is inaccessible to plants. Instead, they need the nitrogen to become “fixed” in the soil, so they can make use of it. Plants will fix nitrogen naturally (but very slowly) and humans have learned that by fertilizing their fields, they can speed this process up.
Guano Islands and Fritz Haber
As the world began to grow and Europe and the United States began to industrialize in the early 19th century, they needed more and more fertilizer to keep up with demand. Manure from farm animals was ok, but there was another source that farmers soon tapped into: guano, or bat feces. It turned out that a number of tropical islands were rich in guano deposits, and the United States Congress passed the Guano Islands Act in 1856 empowering US citizens to claim uninhabited islands, and the military to step in when “necessary.” (How to Hide and Empire by Daniel Immerwahr has a few really good chapters on the “Guano Island” period of American expansionism).
The world of fertilizer changed again in 1913 when the German chemist Fritz Haber invented a process to artificially fix nitrogen. This process is the Haber-Bosch process (Fritz Haber developed it with another German chemist named Carl Bosch) and it was revolutionary. The effects of this process are profound: global population grew 5x in the century after its discovery, scientists estimate that 1/3 of all food production is a direct result of the Haber process, and it is also a major driver of CO2 emissions. Essentially, we convert fossil fuels into cheap fertilizer which has fueled the population boom over the last 120 years. Fritz Haber won a Nobel Prize in chemistry for his work, but some of his research later laid the basis for the gasses used in the Holocaust. Haber is a controversial figure, but his discoveries allowed for easier access to cheap nitrogen paving the way for the births of several billion people and a complete transformation of the world economy.
Monetary Policy and So What?
Most currency in history, from ancient Roman denarii to the latest cryptocurrency, is based on some level of scarcity. The currency represents a certain amount of value. The Romans got themselves into trouble when they debased their own coinage, reducing the silver in each coin and causing inflation. This was really bad, because a bunch of heavily armed Roman soldiers would revolt each time they felt they weren’t getting their money’s worth. Today, we see scarcity in the blockchain. The total number of bitcoin is capped, for example, in order to protect again inflation. By tying a currency to something finite and limited, like precious metals or a preset limit, leaders can prevent the currency losing its value and the chaos that can ensue.
Which brings us back to The Expanse and the nitrogen-based currency. Currently, in the 21st Century, we are awash in cheap nitrogen. But imagine being on a space station millions of miles from home. You can only recycle so much, and it takes months or years for a new spaceship to reach you. If something goes wrong, you can’t eat gold. But nitrogen allows you to grow your own food with hydroponics, allows you to be self-sufficient among the stars. Now your money isn’t just tied to an arbitrary unit of value, but rather the building blocks of sustainable life. I think that’s super cool, and it makes my mind go in a million different directions. I don’t think a nitrogen currency would work, but I also don’t think we have to wait until we live in space to start aligning our economy with our basic needs. We can start making changes today.