No, not THAT kind of ammonia!

That kind of ammonia (“household” ammonia) isn’t used for cleaning around the house much these days. People switched to bleach or one of the many other cleaning products out there that don’t smell so bad.

Household ammonia is a dilute solution of ammonium hydroxide, made by bubbling ammonia gas into water. Ammonia gas (NH₃) is synthesized from hydrogen and nitrogen. That process, called Haber-Bosch, was invented in the early 20th century and revolutionized world agriculture. No longer did farms have to depend on an increasingly variable supply of biological materials like manure, guano, kelp, fish meal, etc. Now ammonia-based nitrogen fertilizers could be manufactured to meet demand.

In some cases ammonia gas is injected directly into fields. In other cases the nitrogen is made available in a different compound, synthesized from ammonia. Regardless, ammonia production is crucial to feeding the human race. And ammonia production is costly, energy-wise. It is estimated that 1% of all the world’s energy is used to make nitrogen-based fertilizers. Right now most of the hydrogen used in ammonia synthesis comes from natural gas, and the high-pressure steam heating required is supplied by fossil fuels. There are greener pathways for making ammonia, but none currently compete with existing technologies.

The “organic” farming movement has gained a lot of traction in the US. We are wealthy enough and have an abundant food supply so consumers can be picky about what they eat and where it comes from. Much of the world does not have that luxury. But the organic farmers have a point: industrial agriculture is not sustainable. Right now we are eating our oil! The energy requirements of the modern farm are immense and as the world population grows the demand for food will increase and thus more and more energy will be required.

Advances in herbicides, pesticides, fertilizers and soil amendments, tractors and farm machinery, crop breeding, and genetics have enabled fewer and fewer people to grow more and more food. Before WWII American farmers could get, if they were lucky, two tonnes* of corn (maize) per hectare**. Now they routinely get ten! But that five-fold increase is not going to happen again. We aren’t going to get some magic technological bullet that will suddenly double our yields. Growing enough food to feed the world will continue to require very large inputs of energy.

Innovations will be needed of course, this is why people are excited about biotechnology. GMOs are here to stay and we’ll need more of them in the future. But we also have to face our choices and our consumption patterns. There is a belief that advances in science will be sufficient to take care of our environmental problems. This is not so. Most of our problems are social, economic, and political. Solving those kinds of problems is much trickier than inventing new stuff. We have to work together and you know how hard that is! The whole world wants to eat as well as we do. It’s a fair thing to want. What’s it going to take to get there?

*tonne = 1 metric ton = 1000 kilograms = approx. 2200 pounds

**hectare = 10,000 square meters (100m x 100m) = approx 2.5 acres