The Silent Power: How Fertilizer Quietly Fed—and Changed—the World

Look at the person next to you. Now look at yourself. There’s a fifty percent chance both of you are alive today because of a single industrial process patented in 1908. That’s the estimate. About half the global population. Four billion people. And just like we saw with plastics in the last episode, this is another one of those forces that completely remade the world while almost no one was paying attention. It’s just… fertilizer. It's never just fertilizer. Before the early twentieth century, human civilization had a hard ceiling. It was nitrogen. The amount of food you could grow was directly tied to the amount of usable nitrogen you could find in nature—manure, certain plants, guano deposits.

And we were running out. So the whole world was facing a Malthusian cliff. A point where population outgrows the food supply. Exactly. And then two German chemists, Fritz Haber and Carl Bosch, did something that was considered impossible. They figured out how to pull nitrogen—which makes up seventy-eight percent of the air we breathe—and fix it into ammonia. They made fertilizer out of thin air. They made fertilizer out of thin air, high pressure, and a lot of heat. The science from Haber was the breakthrough, but the scaling by Bosch is the miracle. He built a factory, the first one in Oppau, Germany, that could withstand pressures and temperatures that were unheard of.

He tested 2,500 catalysts just to find the right one. And this is the process that unlocks modern agriculture. It’s the key that turns the engine. The Green Revolution of the mid-20th century doesn't happen without it. US corn yields, for example, went from under 1,500 kilograms per hectare in the 1930s to over 10,000 today. A seven-fold increase. That’s the Haber-Bosch process at work. We didn't just get more food. We got a different kind of world. A world that could support a population of eight billion people instead of maybe four. So this is the pattern again, isn't it?

A miracle technology that solves an existential problem, but comes with a hidden cost. With plastics, it was waste. What's the cost here? Energy. And carbon. The process is incredibly energy-intensive. Today, ammonia production uses about two percent of the world’s entire annual energy supply, mostly from natural gas. Wait—two percent of ALL energy? For fertilizer? For fertilizer. And it’s not just the CO2 from burning the fossil fuels to power the plants. The fertilizer itself, when it’s spread on fields, releases nitrous oxide. Which is… bad? It's about three hundred times more potent as a greenhouse gas than carbon dioxide.

So every ton we produce to feed ourselves is also powerfully warming the planet. It's the ultimate double-edged sword. So the invention that saved billions from starvation is now a primary driver of the climate crisis that threatens billions. That's the dilemma. And it gets more complicated. The supply chains are fragile. Key ingredients, like phosphate rock, are concentrated in just a few places, like Morocco. And we saw what happened when the war in Ukraine disrupted grain and fertilizer shipments. Food security is national security. It feels like we're caught in a trap of our own making.

We can't turn it off—people would starve. But continuing on this path is unsustainable. That's exactly right. The conversation now is about how to break the pattern. Can we make "green ammonia" using renewable energy instead of natural gas? Can we engineer crops that need less fertilizer? We solved the nitrogen problem a century ago. But in doing so, we created an energy and climate problem. And the clock is ticking on that one, too. We need to feed a projected 9.3 billion people by 2050. Right. The demand is only going up. So the question becomes, can we invent our way out of this problem a second time?