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Robert Richardson worked on the superfluid properties of helium – now he worries that we are squandering our supplies of the gas

Most of us think of helium as something to fill balloons with or that makes your voice go funny when you inhale it. Why does it matter that helium supplies are running low?

There are some substitutes, but it can’t be replaced for cryogenics, where liquid helium cools superconducting magnets for MRI scanners. There is no other substance which has a lower boiling point than helium. It is also used in the manufacture of fibre optics and liquid crystal displays.

The use of helium in cryogenics is self-contained, in that the helium is recycled. The same could be done in other industries if helium was expensive enough that manufacturers thought recovering it was worthwhile.

Surely industry must be paying more and more for helium if it is in short supply.

No, the price is dictated by a calendar. The US government established a national helium reserve in 1925, and today a billion cubic metres of the gas are stored in a facility near Amarillo, Texas. In 1996 Congress passed an act requiring that this strategic reserve, which represents half the Earth’s helium stocks, be sold off by 2015. As a result, helium is far too cheap and is not treated as a precious resource.

Oil companies such as Exxon have invested heavily in extracting fossil fuels from shale, which may also contain helium. Could this come to our rescue?

The so-called Eastern oil shale in Kentucky and Ohio, which is also a source of natural gas, contains only trace amounts of helium, not the relatively large 0.5 to 2 per cent found in natural gas reserves in the American West. The same is true of North Sea gas and wells in Europe.

Say we do run out of helium – can’t we just make the stuff from something else or purify it from the air?

There is no chemical means to make helium. The supplies we have on Earth come from radioactive alpha decay in rocks. Right now it’s not commercially viable to recover helium from the air, so we have to rely on extracting it from rocks. But if we do run out altogether, we will have to recover helium from the air and it will cost 10,000 times what it does today.

The shortage of helium has been talked about for a while. Are things really getting that urgent now?

Maybe in Europe there has been a conversation, but not in the US – and the US supplies nearly 80 per cent of the helium used in the world. The problem is that these supplies will run out in a mere 25 years, and the US government has a policy of selling helium at a ridiculously low price.

What should the US government do instead?

Get out of the business and let the free market prevail. The consequence will be a rise in prices. Unfortunately, party balloons will be $100 each rather than $3 but we’ll have to live with that. We will have to live with those prices eventually anyway.