It’s a gas, gas, gas - helium supply

Materials World magazine
,
1 Feb 2014

No doubt as you read this, many New Year’s resolutions will be as deflated as that helium-filled balloon picked up at the New Year party. But while there will always be next year to make fresh resolutions (and why wait until then?), the days of the helium-filled party balloon could soon be numbered.

Or so we’re told. For it turns out that the second most common element in the universe could become in very short supply here on Earth.  

Mind-boggling quantities of new helium atoms are constantly being created by nuclear fusion of hydrogen in large stars, including our own sun. But that isn’t much use to us down here where the helium we extract from natural gas reservoirs is the product of millions of years of radioactive decay of uranium and thorium within Earth’s crust. Not only that, but the extremely low atomic mass and structure of helium means that once it is used, it is virtually impossible to recapture and recycle – instead rising into the upper reaches of the atmosphere and eventually escaping into space. Like the natural gas production it is associated with, helium is a finite resource. However, unlike the abundant quantities of natural gas found widely across the globe, relatively few gas reservoirs have a helium content sufficiently high to be commercially extractable. Yet the US Geological Survey estimates global helium resources to be around 52 billion cubic metres (proven, probable and possible reserves). Compared to an annual consumption of 170 million cubic metres, this equates to more than 300 years’ production. So why the rash of stories in 2013 about helium shortages?  

Not surprisingly, the facts are often overlooked in pursuit of an attention-grabbing headline – in this case, the difference between reserves, production, storage and supply of a resource. That, and an interesting legacy of the First World War. Back in 1925, worried by the military threat posed by German airship technology (the development of fixed-wing aircraft having been banned by the Treaty of Versailles), the US Government established the National Helium Reserve to stockpile the gas for its own use, and continued to maintain the reserve throughout the Space Race and Cold War of the 1960s, using helium as a rocket coolant. But by the 1990s, with the development of semiconductors and MRI scanners, civilian helium use in cryogenic, pressurising and purging applications far exceeded the US Government’s strategic requirements. So in 1996, Congress decided to sell off the loss-making reserve and trust in the private sector to fill the supply gap. The trouble is, it didn’t. Faced with a legal and impending requirement to close the reserve, and with it nearly one third of the world’s supply, in May 2013 Congress voted to keep it going.  

This is a good example of how price and supply control by government can end up distorting a market, and contrarily how market forces cannot always be relied upon to correct an imbalance. But for now at least, a crisis has been averted. Which is just as well, because if you need a cryogenic application below -256°C, then there is no alternative to this enigmatic little gas molecule. Perhaps using it for party balloons isn’t the most sensible thing to do after all?