GoKawiilThe war in Iran, and the subsequent closure of the Strait of Hormuz, has unfortunately made us all familiar with details of the petroleum supply chain that we could formerly happily ignore. Every day we get some new story about some good or service that depends on Middle East petroleum and the production of which has been disrupted by the war. Fertilizer production, plastics, aluminum, the list goes on.
One such supply chain that’s suddenly getting a lot of attention is helium. Helium is produced as a byproduct of natural gas extraction: it collects in the same underground pockets that natural gas collects in. Qatar is responsible for roughly 1/3rd of the world’s supply of helium, which was formerly transported through the Strait of Hormuz in specialized containers. Thanks to the closure of the strait, helium prices have spiked, suppliers are declaring force majeure, and businesses are scrambling to deal with looming shortages. (For many years the US government maintained a strategic helium reserve, but this was sold off in 2024.)
What I find interesting about helium is that in many cases, it’s very hard to substitute for. Helium has a unique set of properties — in particular, it has a lower melting point and boiling point than any other element — and technologies and processes that rely on those properties can’t easily switch to some other material.
Helium production
Helium is the second lightest element in the periodic table (after hydrogen), and the second most common element in the universe (also after hydrogen). But while helium is very common on a cosmic scale, here on earth it’s not so easy to get. Because helium is so light, it rises to the very top of the atmosphere, where it eventually escapes into space. So essentially all helium used by modern civilization comes from underground.
Helium is produced via the radioactive decay of elements like uranium and thorium, and it collects in underground pockets of natural gas. This source of helium was first discovered in the US in 1903, when a natural gas well in Kansas produced a geyser of gas that refused to burn. Scientists at the University of Kansas eventually determined that this was due to the presence of helium. Like petroleum, helium has collected in these pockets over the course of millions of years, and thus (like petroleum) there’s a limited supply of underground helium that can be extracted. As with petroleum, people are often worried that we’re running out of it.
Because helium is a byproduct of natural gas extraction, and because only some natural gas fields have helium in appreciable quantities, a small number of countries are responsible for the world’s supply of helium. The US and Qatar together produce around 2/3rds of the world’s helium supply. Russia, Algeria, Canada, China, and Poland produce most of the remaining balance.
Elemental helium has a few different useful properties. The most important one is that, thanks to the small size and completely filled outer electron shell of helium atoms, helium has a lower boiling point than any other element. Liquid helium boils at just 4.2 kelvin (-452 degrees Fahrenheit). By comparison, liquid hydrogen boils at 20 K, and liquid nitrogen boils at a positively balmy 77 K.
Its low boiling point makes helium very useful for getting something really, really cold. When a liquid boils, it transforms into a gas, and during this process it will pull energy from its surroundings due to evaporative cooling. This is why your body sweats: to cool you down as the liquid evaporates. When a liquid has a very low boiling point, this heat extraction happens at a very low temperature. Helium also stays a liquid at much lower temperatures than other elements. Nitrogen freezes solid at 63 K, and hydrogen freezes at 14K, but at atmospheric pressure helium stays a liquid all the way to absolute zero. If you need to cool something to just a few degrees above absolute zero, liquid helium is essentially the only practical way to do that.
Helium also has a few other useful properties. As we noted, helium is very light: it will naturally rise in the atmosphere, which makes it useful as a lifting gas. Thanks to its filled outer electron shell, it is inert, and won’t react with other materials. Helium also has high thermal conductivity — at room temperature, helium can move heat about six times better than air.
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